# 12v Boost Jumper powers 9.6v Ryobi Drill



## MrAl (Mar 29, 2005)

Hi there,

I just thought i would let others know that i finally got
around to trying this trick and it worked very well.

The story goes like this...

A while back i bought a Ryobi Drill at Home Depot and
it worked fine at first, but within about 6 months one
battery pack died out suddenly, and i didnt even use this
thing more than a few times.
Ok, so i tried to return the pack and found that it would
mean driving about 20miles or so to have them 'test' the 
pack to see if it was really defective (as if i didnt know
already). Since that was a hassle, i replaced the batteries
myself with fairly decent NiCd's. Ok, so that pack isnt
too bad now and works pretty well.

About a week ago i went to use the OTHER pack that came
with the drill and THAT ONE WAS COMPLETELY DEAD TOO!!
I've never seen batteries ALL die in a pack like this
before. Usually ONE or at most TWO die but the others 
are still good.

I decided to try a new idea this time because i didnt 
feel like shelling out $40 for new batteries AGAIN.
I had purchased one of those automobile 12v jump packs
a while back and decided it should get used more than
it does now, so i connected it to the Ryobi 9.6v drill
though a high current diode and now the drill works again.

The jump pack had a 12v cigar lighter outlet, so i used
a heavy cord with a 12v cigar plug at one end so it would
plug right in. I removed all the batteries from the
old Ryobi battery pack and installed a 1N1188 diode (35A).
After drilling two small holes for the wire and soldering
it on the diode and the other to the negative terminal of
the battery pack, i closed everything up and plugged it in.
Now the drill has more power than it ever did /ubbthreads/images/graemlins/smile.gif

Under load the drill gets about 10v or so, which is safe
because the drill packs typically used to charge up to
10.4 volts or so.

The diode was bolted to a small heat sink also for
more continuous operation.

The drill is now still portable, but the jump pack has
to follow it. The up side to this is that the old batt
packs were rated about 1.3 Ah while the jump pack i think
is about 24 Ah, meaning it will run the drill for about
18 times longer than with the batt pack /ubbthreads/images/graemlins/smile.gif Nice!

The cord is about 6 feet long, but if you decide to do
this and want a longer cord make sure to use nice heavy
wire like 12 gauge or so.

The diode can be any high current si diode (not Schottky 
though). A 35 amp rating should keep it running for a long
time. If you plan to keep the drill running constantly
for long periods it might be a good idea to use a larger
heat sink too. You can probably find one that fits right
inside the old batt pack. If you want to try running
without the diode that may work ok too, but i didnt do
this because the 12v is above the 10.4v max of the normal
battery pack so i didnt want to take a chance of burning
out the drill electronics (used for the variable speed).
If you're drill doesnt have variable speed, you probably
really dont need the diode.

Take care,
Al


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## Lynx_Arc (Mar 30, 2005)

I did a *trick* myself the other day similar. I have a portable soldering iron... isotip orange 3 hour charge etc. I replaced the batteries with some I rescued from a bad drill pack but found the batteries disharged when I needed it, so I had recently bought a 6v spring top SLA replacement battery at walmart for $4 on closeout. I measured the voltage on the end and determined the polarity, hooked up the 6v battery to the iron when I was ready to use it and it worked perfectly, I soldered the broken PC speaker wire on my computer and after I was done the batteries in the iron was nearly charged. I have used this trick before with an alkaline 6v lantern battery to solder a bunch of stuff in my car when the battery in the iron got weak. You can also use 6v lantern batteries to power a lot of 9v stuff too, like small stereos etc.


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## BatteryCharger (Mar 30, 2005)

I've been using a 14.4v lithium ion pack on a 9.6v drill. Gives it quite a bit more oompff. /ubbthreads/images/graemlins/smile.gif


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## MrAl (Mar 30, 2005)

Hi again,

Lynx:
Oh that sounds interesting...you gave me the idea of
two 6v in series in a pinch also to run my drill.

BatteryCharger:
And i was afraid to use 12v he he. Are you using a drill
that has variable speed (not speed selections but a
continuous variable speed)?

Take care,
Al


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## Lynx_Arc (Mar 30, 2005)

MrAl, that gives ma an idea also, making an adapter for my isotip to plug into a cigarrette lighter with optional clipon leads so I can use it remotedly off any 12vdc source. It would be nice to find a 12v soldering iron I could use off the cheap $3 SLA gel cell I got from a walmart clearance.


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## MrAl (Mar 31, 2005)

Hi there,

Lynx:
I have a Radio Shark (he he) 12v soldering iron that
works pretty well. I dont know if Radio Shack has this
anymore but you could check i guess. I was pretty happy
with the power rating (probably about 30w).

Take care,
Al


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## PeLu (Mar 31, 2005)

I know several 9.6V and 10.8V drills and they all use a motor rated at 12V anyway.


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## Lynx_Arc (Mar 31, 2005)

why they dont make soldering irons that work on drill motor battery packs I haven't figured out yet.


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## Vikas Sontakke (Mar 31, 2005)

This is a good idea but have you tried to "jump" the dead cell? I have had mixed success in getting the dead cell to come alive but the success was short-lived.

If the drill has to be tethered to a boost pack, why not just use a "real man's" drill plugged into 110V supply  Seriously, I had an old 110V drill which I have no idea where it is now. I have been using Ryobi portable drill/flashlight combo for last 5 years.

- Vikas


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## MrAl (Mar 31, 2005)

Hello again,

PeLu:
Did they have variable speed (continuous variable speed)?
I wasnt worried about the motor, just the electronics, but
that's good to know anyway.

Lynx:
Im sure with the right batt pack and a 12v iron you could
get it to heat up /ubbthreads/images/graemlins/smile.gif

Vikas:
What dead cell?
Yes, the drill has to be connected to a somewhat heavy
boost pack, but that means you still dont need a 120vac
outlet. This is a big advantage sometimes, and with the
boost pack you get a lot of power from the drill too and
VERY long run time (18 times longer than a single normal
batt pack).
I have a 'plug in the wall' drill too but those kind arent
usually made for high torque like putting in screws and
stuff like that.

Take care,
Al


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## PeLu (Apr 1, 2005)

[ QUOTE ]
*MrAl said:*Did they have variable speed (continuous variable speed)?
I wasnt worried about the motor, just the electronics, but
that's good to know anyway.

[/ QUOTE ]

Both. It was because I have spare motors for some of the drills (rotary hammers actually) on expedition and I found out that the 775 motor is widely used on 12V (maybe even more). 
Maybe I will change the old Makita drills (which still perform perfectly) to use model flyer 12V packs. Normally they use a strange 9x 3/5D cell pack. 
And the spare part switches (with variable speed) I've seen are only rated for 12V and something like 18V, but of course this is no prove.

What may be much more of a problem is how long you use them. They are just not made for a 20min non stop drill.


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## MrAl (Apr 1, 2005)

Hi again Peter,

Very interesting.
Yes, i dont intend to run them for very long at a time.
I maybe put in up to eight screws (needing lots of power
however) and then probably not use it for another 20 mins
to a month or so. Just really want to have it ready when
i really (all of a sudden) need it. Couldnt rely
on the Ryobi drill packs at all so i wonder if i got a
bad bunch? But i've never seen ALL the batteries in a pack
go out like that all at the same time either.

Take care,
Al


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## Lynx_Arc (Apr 1, 2005)

The one advantage I find is SLA cells don't tend to self discharge much over time compared to nicads/nimh cells. I have had so many rechargable devices with nicads that I use once or twice a year that end up uselessly dead when I need them that a decent SLA would be better suited if size permitted for such occasions. I wonder what the capacity/size comparison for nicad vs SLA cells is?
Perhaps if SLA cells could be made in common subC, AA, etc it would replace nicads in rarely used gadgets.


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## MrAl (Apr 2, 2005)

Hi again Lynx,

I like the large SLA's too for some things, but LA is
not very efficient compared to the others out there.

My big 24Ah boost pack was laying around too much not
doing anything so i decided it was time to use it for
something /ubbthreads/images/graemlins/smile.gif

Take care,
Al


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## cobb (Apr 2, 2005)

Wow, neat idea. I would be tempted to make the battery pack a back pack so it would be like one of those guns from ghost busters. Although I guess a 24 amp hour battery weights about 24 pounds. 

I know many electrical motors you can use extra voltage to run them, just got to be careful you do not spin them up soo fast they throw the windings. THey can also make up to 400% their rated torque for 4 minutes or less with unlimited amps before you toast them. 

I wonder if you can power a regular soldering iron on 12 volts? I know you can light regular house hold bulbs that way. THe wireless soldering iron I used at a former job used lighter fuel and the cap contained a striker to light it. My soldering gun which is 100 watts uses a large internal transformer and the bit is really a heating element.


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## Lynx_Arc (Apr 2, 2005)

My guess is most soldering irons (regular, unregulated) are just essentially a large resistor that is heat resistant. it pumps out heat and the tip pulls off the heat dissapating it into soldering and the air. 12v irons probably have a different resistance and running a 120v iron off 12v most likely would only heat up perhaps 1/10 as hot so a 30 watt iron may turn into a 3 watt iron or even less. Someone said earlier they do have 12v irons, if there are irons out there that can operate from about 9-15vdc I would like to know the current draw at 12v or even the resistance because it would be nice to make a battery powered soldering station using either a small motorcycle battery of an SLA or gel cell. I have had many times I have had to run long cords to cars to work on wiring when a lighter cord powered iron would do the trick easily.

oh, I found a couple of used nicads subC cells and replaced the ones in my isotip iron. I have a 1 hour recharge version and the batteries in it are bad also, I probably will pull some cells out of a drill motor pack for it also. I am guessing nicad cells will tolerate a 1 hour charge, just heat up more.


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## MrAl (Apr 3, 2005)

Hi again,

cobb:
Thanks for reminding me about the no load spin of the motors,
as i'll be careful now to make sure i dont run the drill
at full speed (trigger all the way in) when it's not
doing any work. I can probably remove the big diode 
too (35 amp rating!) and just be careful not to run it
up to full speed no load.
I imagine that if you use a converter that converts from
12vdc to 120vdc you can run most resistive type soldering
irons that normally run on 120vac house power. You can
also use a small converter for 12vdc to 120vac (like a
50 watt model). The inductive type irons will require ac 
for sure. Radio Shack did have a 12vdc soldering iron for
sale too, if they still do have it that's an option also.
I was going to look into one of those 'fire' type irons
too at some point. That's even more portable i guess.
Yeah, those big 100 watt guns use ac to step down the
voltage (and step up the current) to run the tip hot.

Lynx:
Yes, most are resistive but as mentioned those big guns are
transformers which require ac to run.
I dont think a 120v iron would get hot enough running on
12vdc, but yes there are 12vdc irons out there and they arent
that expensive. The big guns however need 120vac so you 
might need an inverter to go from 12vdc to 120vac.
Those small inverters arent that expensive either.


Take care,
Al


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## Lynx_Arc (Apr 3, 2005)

MrAl 
I rarely use a soldering gun as my normal use *iron* has is a 50 watt iron plated Ungar. It is rare when I need to resort to a gun but I do have a dual output one somewhere with about 12 or so extra tips, if anyone needs tips to soldering guns I may have extras but I would have to check to see what they fit. I may measure the current draw on my isotip iron and build a voltage regulator for running it off of 6v or 12v DC. I have a second isotip iron that is a 1hr charge that the battery is toast, perhaps I can remove the batteries and put a 12v to ~3v voltage regulator inside it instead and wire up a plug for 6/12v input. I could even make an LED bulb for it instead of the incan one if I could run the iron at around 4v.


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## MrAl (Apr 5, 2005)

Hello again,

Oh i see...50 watts that's pretty high too.

I ran my smaller drills (4.5v) off of a computer 5v supply
just to test it. It worked but the supply only puts out
7.5 amps so the drill doesnt have a real lotta power.

Take care,
Al


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## Lynx_Arc (Apr 6, 2005)

Yea 50 watts is for impatient people that don't like to wait around on a solder joint /ubbthreads/images/graemlins/grin.gif
Once you get use to it, it is kind of hard to go to a 25-30 watt iron unless you are soldering micro circuitry.


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## MrAl (Apr 6, 2005)

Hi again Lynx,

OH yeah, he he, i have one i think is about 40 watts, and
the tip is a quarter inch diameter with a chisel tip, and
that thing solders fairly large battery terminals and other
connections like that pretty quick. I'm hooked on it,
except when i have to do real small joints like for ic's,
where i take out the tip and insert a nail or something or
use my small 25w iron.
I'd be lost without it now, and i'd have to get another
one if it ever bit the dust.

The 12v Radio Shack iron isnt bad either...with quite a
tip on it too. It's pretty decent for 'normal' connects
but when i did my alternator terminal i had to use
a 100 watt gun, and even that took a few minutes to heat
the joint up properly. I was thinking if i had one of
those tips they put on large propane torches (like a
half inch diameter or so) it would have been even faster,
but i dont know if they make those anymore...


Take care,
Al


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## Lynx_Arc (Apr 6, 2005)

My iron has a chisel tip on it about that size, I once wrapped a piece of bell wire around the tip so I could solder under an LED where it had broken loose, worked like a charm although it took awhile to heat up the joint due to the smaller tip size. What I would like to see is a 4AA cell drill/driver with a clutch and a soldering iron attachment. You could run it off of nimh cells and use it for all sorts of things.
I never have tried the small butane irons, I have a propane torch somewhere for heating stuff up. I stopped by radio shack to see if they had any 12v irons and didn't see any there, guess it wasn't a hot seller... or HOT enough seller.
I should check around and see if I can adapt my isotip for use with nimh subC cells, perhaps the charger can be modified as most nicad subC cells tend to be around 1300mah compared to 3500+nimh cells.


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## MrAl (Apr 7, 2005)

Hi again Lynx,

I dont see the 12v iron on the RS web site either so maybe
they dont carry it anymore.
I did see a dual heat iron for 120vac though which looked
interesting.

Take care,
Al


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## Lynx_Arc (Apr 7, 2005)

Do they even make a drill motor that has a 12v lighter adapter for recharging? It would probably have to be a 12v or less battery pack otherwise you would need a boost circuit to charge it and that may end up adding more cost than buying a cheap voltage inverter to run 120vac to a charger.


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## MrAl (Apr 8, 2005)

Hi again Lynx,

Oh gee i dont know, but that's an interesting idea.
I dont imagine the charge circuit would have to be
'too' expensive, maybe 100ma charger, but yeah that would
add to the cost im sure.

Another idea:
One that could run off of 12v or 120vac wow. It would
have to come with both plugs.

The thing i like about my 'cordless' drill even if i were
to run it off of a power supply plugged in is that the
speed/torque characteristic is very different from my
120vac drill which makes it more suitable for putting in
screws and stuff like that. The 120vac drill is more for
drilling. If one could do both, that would be great.
If it could plug into 12 or 120v that would be even better.


Take care,
Al


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## Lynx_Arc (Apr 8, 2005)

120vac would be fairly easy if the drill motor doesn't take a huge amount of current you could just get a walwart that bypasses the barrery pack and/or just charges it as it is being used. Perhaps they could have dual windings, one suitable for 12vdc another for 120vac, all in the same drill motor but I am thinking this wouldn't be cost effective.

My idea was so when you were out somewhere else away from 120vac sources you could recharge your drill from a car/boat etc battery source. Using a 12v sla would be easy, all you would need to do is limit current to the battery for charging off another battery with/without an alternator running. If you got a drill that runs off nimh AA cells you could get a decent cheap car charger for it.


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## MrAl (Apr 8, 2005)

Hi again Lynx,

Sure Lynx, that's certainly a good idea. My problem in
the past with 'cordless' drills is that when i went to 
use them (several models) if the pack was run down i'd
have to wait for it to recharge, so im looking for ways 
to avoid the recharge time, which means direct plug in
to whatever...car/boat/house/UFO... /ubbthreads/images/graemlins/smile.gif

As i was saying, 100ma isnt hard to generate even if it
has to be stepped up from 12v to 18v (for some of the newer
cordlesses). We could develop a circuit right here if
you're interested? Multiple output voltages would be nice
so everyone could use it with their own personal drill.


Take care,
Al


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## Lynx_Arc (Apr 8, 2005)

Yea, I have the same problem with cordless stuff.... either you have to leave them on the charger all the time which seems to lead to early death of the batteries, or you end up finding them dead 6 months later when you use it. It would be nice to have a circuit that would not continuously trickle charge batteries but instead perhaps check them once a week or so and trickle charge them them. A 12v adapter would be nice but my guess is unless you can generate charging times of less than 3 hours, or direct drive off of 12v most people wont find it overly useful. When you find a battery dead in a rechargable gadget is when you are looking to use it right at that moment. I find I usually cannot wait more than an hour or so before I start looking for an extension cord and outlet. 

I wonder what the charge current for an average nicad pack would be to charge it in under 3 hours from *weak* or barely dead.


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## evan9162 (Apr 8, 2005)

I scrapped the charger for my Sears cordless drill (10.8V), and instead rigged it up to charge from my custom made NiCD/NiMH charger (based on a Max 713 charge controller). I can fully charge the pack in about an hour. The charger that came with the drill was a 15V power brick with a diode and resistor in the charging base, and an LED to indicate power. Way easy to overcharge and kill the pack in no time.

I would venture a guess that a majority of power drills use NiCD sub-C cells, probably in the 1700mAh to 2000mAh capacity range. So a 1 hour rate of 1.8A is reasonable and easy to accomplish, and is better for the cells than constant overcharging.


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## Lynx_Arc (Apr 8, 2005)

I have seen a lot of drill packs listed from 1300mah to 1700mah. I suspect the *premium* brand expensive packs probably get higher output cells. I like the idea of SLA in the fact I haven't notice any self discharge of them. If there is any it must be rather low because I have bought SLA gel cells batteries I know have been sitting for 6 months in a store and found most of them fully charged with exception of ones that tell you to charge before using them.

Perhaps someone needs to make a set of universal battery packs that can but used for everything. I am dismayed at companies changing their battery pack design for their drill motors every few years in order to force most people to buy a new drill because the battery packs are no longer made. Let's face it... most of the batteries in the packs are the same with possible exception of higher capacity. Black and decker recently changed their battery packs and I have a nearly new 9.6v drill motor and no packs in the store for it now. A universal pack would be more conservationalist. You could also use it for radios, portable tv sets, computer game stuff etc. My feeling is companies are trying to make extra profit on proprietary packs by changing drill designs every few years..... with NO improvements to them warranty the change.


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## MrAl (Apr 9, 2005)

Hello again,

Evan:
Max 713..how many external parts required?

Lynx:
Yeah, i noticed that too and that the packs are pretty
expensive. If you have the inclination you may wish
to build yourself a jump pack adapter for your drill like
it did. It's still portable...use say an 8 foot wire.
You wont regret it i promise /ubbthreads/images/graemlins/smile.gif
Later, if you have other drills you can convert them too.

evan & Lynx:
How do you's intend to charge the NiCd's when they are all
in series...after all, fast charging like 1 hour is ok but
for that heavy charging usually you want to detect minus
delta or something like that which really requires measuring
each cell's voltage while the charge is in progress.
I guess you could use a thermistor? and look for a quick
rise in temperature?

Take care,
Al


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## evan9162 (Apr 9, 2005)

Mr Al,

For my charger setup, a whole hell of a lot of external parts! /ubbthreads/images/graemlins/tongue.gif But I have it configured to allow me to change cell count, charge current, backup timeout, and there's an external thermistor for charge termination.

Building a basic 712/713 charger does require quite a few external parts. For a fixed setup without temperature sensing, it's about a dozen external parts. Add probably 6 more to support a thermistor.

The 712 does 0 delta-V termination, while the 713 does -50mV delta-V termination. They both have a backup timer as well as temperature termination.

I've charged lots of multi-cell packs with this charger without problems. The temperature sensor is a must, since temperature termination has almost always kicked in before even 0 delta-V when charging NiMH packs. My drill packs are NiCD, and are just barely warm when the charge terminates from delta-V. I haven't noticed any reduction in usage time from the other charger - but even if they are undercharged slightly, that's better for the cells anyways.


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## Lynx_Arc (Apr 9, 2005)

They could easily build in temperature sensors and possibly even a small circuit in battery packs at the current cost of them. I know from the prices of packs of cheap chinese drill motors that it doesn't cost near $40 for a 18v nicad pack to be made. A universal pack could be made with enough guts to tell a smart charger how to charge it for a decent price. That would allow variable charging rates, fast or trickle etc. I would guess smart chargers trickle charge at considerably lower rates than standard slow trickle nicad chargers which most likely would reduce the rate at which nicad batteries seem to die when they are constantly on a charger waiting.


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## MrAl (Apr 10, 2005)

Hi again,

evan:
Thanks for the info. At some point i'd like to contruct a
4 cell charger that does each cell individually (NiMH).

Lynx:
Yes, i like the idea of a built in temperature sensor too.
They put so little thought into these packs maybe because
they profit when one goes weak. If they improve the 
quality of the pack they make less money. That's sure
to make crappy packs /ubbthreads/images/graemlins/frown.gif We'll just have to build our
own stuff i guess and it would be nice if we could inform
the general public when something like this is taking place,
which would reduce their motivation to design crappy stuff.
My Ryobi drill itself isnt too bad, but the packs both went 
completely dead. That's not likely unless something is 
defective in the packs, especially since ALL the cells 
in BOTH packs went COMPLETELY dead.

Take care,
Al


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## CNC Dan (Apr 10, 2005)

Just a few things I would like to add.

Some battery packs do have a thermosistor in them. Look for packs with three termonals. One is pos., one is neg. and the other is one side of the thermosistor. The other side of the thermosistor goes to the neg. termonal.


Newer chargers sense the change in voltage as the pack is charged. Many of these chargers will be able to charge diferent voltage packs.

My DeWalt charger can charge packs form 7.2v to 18.0V.

DeWalt seems to have 'keyed' the drill/packs to work with the same voltage. The packs of diferent voltages can be made to fit into your drill if you file away some of the drill's socket where the stem of the pack goes in. Just the other day I saw a 14.4V pack on the street while on my way to work. I picked it up and found that it can fit my 12.0V drill. Works fine, no smoke.

If you have a dead power tool pack, you can get them rebuilt for less than half the cost of a new pack at primecell.com.


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## Lynx_Arc (Apr 10, 2005)

CNC Dan, I believe the dewalt charger is just a current regulating charger. It should charge all packs in the range at the same current regardless of the cells. My dad has one and we had to think about how it could possibly charge different voltage packs without being slow as molasses on the bigger ones and too fast on 9.6v etc ones. I am betting the 14.4v pack being only about 20% higher voltage probably just runs the drill a little faster and isn't overrevving it much..... or dewalt possibly puts the same motor in different voltage drills and just sells them as 12/14.4 etc.
Or.... the drill itself has a fancy inpuf voltage regulator?

I could rebuild packs myself, the hardest parts is getting good prices on cells while matching the mah rating and taking it apart/reassembling it without breaking. 

I am beginning to think there are some cheezy cheap dud cells running around now and then that get into packs because I have heard of more of them going bad in less than a year. Usually you just get one or two bad cells but the pack I had go bad.. all the cells went bad, not at the same time but one after another.


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## MrAl (Apr 11, 2005)

Hi there CNC_Dan and Lynx,

My packs dont have any thermistor, but now that you mention
it i guess it wouldnt be 'too' hard to add 'one'. Thing is,
i'd like to have each cell monitored, not just the whole
pack. I guess one would be better than nothing though.

Yeah, someone else was saying that the drill companys 
sometimes use the same motor in different drills so
you might have a 12v drill motor in a 9v drill.

You guys really have to try this jump pack powering the
drill thing...you wont regret it! Tons of power and 
never runs down he he 
If you dont want to run out and buy a jump pack (i think
cheapest is about $30) then you might try a SLA battery
with some high Ah rating (12 or something). You have
to remember that the tiny NiCd cells are 2Ah at best,
so with even a 12Ah SLA you get six times the run time and
the voltage doesnt load down as much under load too so
you get more power (use a nice heavy cord).

Warning: Once you've tried this you'll never want to go
back to those little bitty NiCd cells again /ubbthreads/images/graemlins/smile.gif

Of course there's the problem of how to connect the
pack to the drill. Mine came with two NiCd packs (both
of which died completely) and i only restored one pack
with new cells, so i had the other with no cells in it
to modify with a cable to the jump pack. Since most
people wont have the second pack, they'll have to rig
something up, possibly making a mold of the pack
shaft with plaster or something or using a whittled piece
of wood with some metal strips to act as contacts.

Take care,
Al


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## eluminator (Apr 11, 2005)

[ QUOTE ]
*Lynx_Arc said:*

I should check around and see if I can adapt my isotip for use with nimh subC cells, perhaps the charger can be modified as most nicad subC cells tend to be around 1300mah compared to 3500+nimh cells. 

[/ QUOTE ]

Wahl iso-tip now makes an iron that uses standard C cell Ni-Cads. It's considerably bigger than the ones with the built-in batteries, but it's not much heavier.

I haven't used mine much but it seems okay. I told the seller to remove the NiCads as I have lots of NiMH and it would save me a trip to the recycler. The only times I've used it, I used NiMH AA cells instead of C cells just to see if it would work. It does work on AA but it takes about 15 seconds to heat up.

http://www.starkelectronic.com/whl7670.htm


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## eluminator (Apr 11, 2005)

My favorite drill by far is a fifteen year old Skil "Skil Twist" cordless screwdriver with a drill chuck that slips in, in place of a screwdriver bit. 

I like the slow speed and the high torque. I almost always drill material that's softer than steel. On printed circuit boards, aluminum, brass, plastic and wood, it's hard to beat. My drill bits are at least 25 years old and they haven't been sharpened, and they are still sharp.

I see Walmart now sells a cordless screwdriver that takes AA alkalines and another one that takes D alkalines. If the old Skil ever dies, I'd buy one of these and use NiMH.


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## Lynx_Arc (Apr 11, 2005)

MrAl you could also remove the batteries from a drill battery pack and wire in an adapter and possibly a charger with cord and then have it dual use. portable charger/adapter. It would be nice to have a thermistor on each cell but you would have to have either a comparator or something to monitor each thermistor individually.. or possibly average them in a parallel or series circuit.

eluminator I have seen the isotip that can use regular batteries but since I already have two of them unless I can trade I would rather repair than buy a third one. 

I have also seen the 4AA drills at walmart and they are interesting but lack one feature I usually desire.... an adjustable clutch. If they incorporate that into them and they have enough torque I would possibly bite at one of them. It would fit in a toolbox easier than a regular nicad battery drill. As far as the D cell version I will have to look at that although I figure nimh AA cells are considerably more cost effective than D alkaline cells are.


----------



## snakebite (Apr 12, 2005)

the nicads have lower internal resistance and perform better.
since more nimh are now produced vs nicads you would think nimh would be cheaper in large quantity and more likely to be used by the mfr. if there ws no compelling reason for nicads.
btw tried sanyo 3300 nimh in isotips and the 2200 sanyo nicads hold voltage up longer.
enough difference to see in the light.
for power tools look at internal resistance first.lower is better.


[ QUOTE ]
*eluminator said:*
[ QUOTE ]
*Lynx_Arc said:*

I should check around and see if I can adapt my isotip for use with nimh subC cells, perhaps the charger can be modified as most nicad subC cells tend to be around 1300mah compared to 3500+nimh cells. 

[/ QUOTE ]

Wahl iso-tip now makes an iron that uses standard C cell Ni-Cads. It's considerably bigger than the ones with the built-in batteries, but it's not much heavier.

I haven't used mine much but it seems okay. I told the seller to remove the NiCads as I have lots of NiMH and it would save me a trip to the recycler. The only times I've used it, I used NiMH AA cells instead of C cells just to see if it would work. It does work on AA but it takes about 15 seconds to heat up.

http://www.starkelectronic.com/whl7670.htm 

[/ QUOTE ]


----------



## snakebite (Apr 12, 2005)

there are a lot of crap cells used in cheap power tools.
even in better brands using quality cells the chargers are constant current with thermal termination.
thats how your dewalt(black&decker)charger works with several voltage packs.dewalt is just a higher end black&decker product.
[ QUOTE ]
*Lynx_Arc said:*
CNC Dan, I believe the dewalt charger is just a current regulating charger. It should charge all packs in the range at the same current regardless of the cells. My dad has one and we had to think about how it could possibly charge different voltage packs without being slow as molasses on the bigger ones and too fast on 9.6v etc ones. I am betting the 14.4v pack being only about 20% higher voltage probably just runs the drill a little faster and isn't overrevving it much..... or dewalt possibly puts the same motor in different voltage drills and just sells them as 12/14.4 etc.
Or.... the drill itself has a fancy inpuf voltage regulator?

I could rebuild packs myself, the hardest parts is getting good prices on cells while matching the mah rating and taking it apart/reassembling it without breaking. 

I am beginning to think there are some cheezy cheap dud cells running around now and then that get into packs because I have heard of more of them going bad in less than a year. Usually you just get one or two bad cells but the pack I had go bad.. all the cells went bad, not at the same time but one after another. 

[/ QUOTE ]


----------



## Lynx_Arc (Apr 12, 2005)

As for the price of nicad vs nimh, I am beginning to think the chemistry of the cells is the main difference in price. I am guessing the isotip iron and perhaps a lot of drill motors have a heavy enough load on them that the batteries internal resistance does factor in the runtime making nicads more preferred due to the low voltage which probably causes a higher current due to power (wattage) demands to get enough heat. I sort of wonder if running an isotip of 4nimh AA cells would work due to more sag... runtime would probably suffer some though. Recharging/running nicad powered devices off 6/12v SLA would give you extra portability and runtime for sure. Perhaps adding one or two or more nimh cells would compensate for voltage sag and increase runtime comparably, but then you could probably also add extra nicad cells for the same effect.


----------



## MrAl (Apr 13, 2005)

Hi again,

Those soldering irons sound interesting. I wonder how long
they take to heat up and cool down?

Take care,
Al


----------



## Lynx_Arc (Apr 13, 2005)

Mine takes about 15-30 seconds or so to heat up I am guessing. Plenty fast enough that you don't need to leave them plugged in and running like regular irons. I find myself using the isotip for a quick solder repair on small joints because of that. Cooling down I am guessing about 5 minutes, I never checked that out, I may be a lot quicker than that and if you want you can just heat sink it on a pair of pliers to cool it down quicker.


----------



## MrAl (Apr 14, 2005)

Hi Lynx,

Gee now i have to wonder why i dont have one yet /ubbthreads/images/graemlins/smile.gif
Im sure i'd use it enough.
I have one of those cold heat units, but then that doesnt
do very big joints.

Take care,
Al


----------



## Lynx_Arc (Apr 14, 2005)

I have never tried one of those cold heat irons. The isotip works well enough when I can feed it juice. I am guessing it is about a 20-30 watt equivelent iron even though it has a small tip it can put a lot of heat into it as long as you hold the button down. The warm up time is a hassle when you are soldering a lot of stuff, and it cools down fairly quickly to the point after a minute or two of not having it on you have to warm it up for 10 seconds or more to solder another connection. I wouldn't count on it to solder any large connections easily as you would have to keep it on for perhaps a few minutes to heat the connection up and when the battery poops out in the midst of things it is umm... upsetting so to speak.


----------



## MrAl (Apr 15, 2005)

Hi again Lynx,

Oh i see. Well maybe it's not the iron for me. I need
a good 40 watts for most of my stuff.
Guess i'll just have to continue to wait for heat up and
cool down :-(

Take care,
Al


----------



## Lynx_Arc (Apr 15, 2005)

Too bad you cannot make heating elements for soldering irons, you could have an iron that runs off of 6v and 12v and have any wattage from 10 to 80 watts. I figure anything above 80 might as well almost be a gun or use a propane torch. It would be interesting to have 2,3, even 4 different coils in an iron to use differing voltage inputs and have different heat outputs. Another thing that could be useful is clip on LED lighting for soldering irons so you can see better what you are soldering.


----------



## CNC Dan (Apr 15, 2005)

[ QUOTE ]
*snakebite said:*
...even in better brands using quality cells the chargers are constant current with thermal termination.
thats how your dewalt(black&decker)charger works with several voltage packs.dewalt is just a higher end black&decker product. 

[/ QUOTE ]

No. The DeWalt chargers use neg. Delta v charge termonation.


----------



## CNC Dan (Apr 15, 2005)

[ QUOTE ]
*Lynx_Arc said:*
CNC Dan, I believe the dewalt charger is just a current regulating charger. It should charge all packs in the range at the same current regardless of the cells. My dad has one and we had to think about how it could possibly charge different voltage packs without being slow as molasses on the bigger ones and too fast on 9.6v etc ones. 

[/ QUOTE ]

It's a constant current supply with a Neg. Delta V charge termanation.
It hits the pack with 2.0A for a while, then samples the pack's voltage.
It does this over and over, compairing the voltage it sees to the last reading. When the voltage starts to drop, it shuts down.


----------



## CNC Dan (Apr 15, 2005)

[ QUOTE ]
*MrAl said:*
..... Of course there's the problem of how to connect the
pack to the drill. Mine came with two NiCd packs (both
of which died completely) and i only restored one pack
with new cells, so i had the other with no cells in it
to modify with a cable to the jump pack. Since most
people wont have the second pack, they'll have to rig
something up, possibly making a mold of the pack
shaft with plaster or something or using a whittled piece
of wood with some metal strips to act as contacts.

Take care,
Al 

[/ QUOTE ]

I did that with my old Sears drill. I had bought a 12V model with that in mind. I used a surplus 12V SLA, and a piece of 10ga. zip cord.
I had been using the SLA for powering my 12V spotlight, so I already had a 12v lighter socket on it. The drills do draw a lot of current, sometimes up to 20A.


----------



## MrAl (Apr 16, 2005)

Hello again,

Lynx:
Yes making your own heating elements would be great. I guess you
could if you really wanted to, but it wouldnt be easy /ubbthreads/images/graemlins/smile.gif
Talking about dual heat setting, Radio Shack now has a model i think
is dual 25 or 40 watts. That's not too bad i guess. It looks like
a regular pencil type iron only with a switch on the side.
Clip on LED idea is cool too. I found one at Staples but i never
used it for that purpose (now that you mention it though i'll have
to try it). It's got a two li cell powered Nichia with a short
flex neck attached to a small plastic clip.

CNC Dan:
OH yes, i was after a 12v model at first myself until i found that i didnt like
the price of them, so i ended up with a piece of junk Ryobi instead he he.
Yeah, the drills draw tons of current. I was thinking of building a down 
converter for my smaller 4.5v drill too to go from 12v to 4.5v or so but 
cant find any chips that go that high in output current so it would have
to be a special design. I already have a few 50 amp MOSFETS so i might just
do it yet! That way i could have one drill with a pilot drill bit and
one drill with a screwdriver bit -- both connected to the 12v pack.
Also have a 3v screwdriver which could also be connected he he.

Take care,
Al


----------



## snakebite (Apr 16, 2005)

[ QUOTE ]
*CNC Dan said:*
[ QUOTE ]
*snakebite said:*
...even in better brands using quality cells the chargers are constant current with thermal termination.
thats how your dewalt(black&decker)charger works with several voltage packs.dewalt is just a higher end black&decker product. 

[/ QUOTE ]

No. The DeWalt chargers use neg. Delta v charge termonation. 

[/ QUOTE ]
the ones i have seen terminate on temp.
could be why i get so many batts of this type in for rebuild.


----------



## CNC Dan (Apr 17, 2005)

[ QUOTE ]
*snakebite said:*
[ QUOTE ]
*CNC Dan said:*
[ QUOTE ]
*snakebite said:*
...even in better brands using quality cells the chargers are constant current with thermal termination.
thats how your dewalt(black&decker)charger works with several voltage packs.dewalt is just a higher end black&decker product. 

[/ QUOTE ]

No. The DeWalt chargers use neg. Delta v charge termonation. 

[/ QUOTE ]
the ones i have seen terminate on temp.
could be why i get so many batts of this type in for rebuild. 

[/ QUOTE ]

Yep. Many older ones did that. My sears charger killed a pack when the thermal sensor failed. Just kept pushing current through. If you look at the packs, many have three connections. The third is for the thermal sensor. Other types have only two connections. No thermal sensor.


----------



## MrAl (Apr 18, 2005)

Hi there,

That's interesting as i was thinking of constructing a
charger for some time now with temperature termination.
I guess i'd use two sensors per cell now and certainly
a back up termination method. I guess i'd have to check
the thermistors now and then too just to make sure
they still work ok.

Take care,
Al


----------



## Lynx_Arc (Apr 18, 2005)

I would think the problem would be if you had a bunch of thermistors, one per cell that you would have to figure out to stop because one cell charged faster or was finished first or wait till the last cell was done. A good compromise is one sensor/thermistor per cell and wire them together in parallel that would be more of an average.


----------



## MrAl (Apr 20, 2005)

Hi there Lynx,

Oh yes, i see what you mean. What i had in mind was
either two or (preferrably) four 'stations' where each
cell would be charged individually, and each cell would
have two thermistors, and the logic would be that 
'EITHER' thermistor could terminate the charging, and
if one's value was too different than the other another
type of error would be triggered to hault the charging too.
I've heard about those thermistors going but i've never 
seen one go yet, but then if it happens the cell would
charge and charge until it leaked and was ruined. I
definitely dont want that to happen, so i'll have two 
thermistors per cell, each cell with it's own charge
control, and a backup timer to shut down after some
max time. I would hope that would solve the problem.
If that doesnt do it, heck, i guess let the cell burn up
hee hee.

Of course if they are in a series pack this isnt possible
because all the cells have to charge with the same current.
That's really a problem because one cell is destined to
charge up before the others.
The solution seems to have them wired in series to run
and disconnect them all and have them charge individually,
but that's MUCH MUCH easier said then done. The wiring
needs to be heavy for the series connections, and that means
having some way of breaking many heavy current connections,
which isnt easy.
One other way that comes to mind is to have each cell 
monitored by it's own sense circuit/thermistor and have
the charge current bypassed once that cell gets to 
a certain temperature so it couldnt rise any longer.
This would require quite a circuit too, however, even
just to monitor say eight cells. I just dont see it as
being that practical.
Perhaps have packs made where the cells can be removed,
sort of like flashlights, but then you have to take 
eight or more cells out just to recharge...not too good
either /ubbthreads/images/graemlins/smile.gif

At least all of 'my' NiMH cells are not in packs, so
i can do the individual charge thing.

Take care,
Al


----------



## Lynx_Arc (Apr 20, 2005)

I don't have a fancy multicell charger and have a few packs I bought that came out of old cell phones, mostly A type cells. I hook them up one at a time to my rayovac 1 hr charger and it works but takes awhile for a 5 cell pack (5 charging cycles). A compromise could be charging the pack till any one cell registers done then going back one by one topping off all cells indivually one at a time. This would take perhaps the least amount of time and wouldn't involve breaking connections between cells, but would require extra wiring to accomplish or bare cell packs where battery access is available.


----------



## MrAl (Apr 21, 2005)

Hi Lynx,

Oh yes, that's not a bad idea. Would take extra wiring
for the charge leads (one per cell plus a ground) but
that doesnt have to be super heavy duty.
Only thing then is that for an eight cell pack there'd
have to be eight leads plus a ground coming out of the
pack, unless the charger could be built into the pack.
The charger would have to
be capable of being connected to either of the eight cells
when it came time to top off the cells one at a time.
Would be very interesting.

Take care,
Al


----------



## Lynx_Arc (Apr 22, 2005)

perhaps something easier would be to have the wires to each cell.. charge them all and remove cells that are not even compared to the rest replacing them with more evenly matched cells until you have a matched pack. Then you wouldn't need to mess with all sorts of sensors or charging one cell at a time because all the cells would be matched.


----------



## NewBie (Apr 22, 2005)

[ QUOTE ]
*Lynx_Arc said:*
Too bad you cannot make heating elements for soldering irons, you could have an iron that runs off of 6v and 12v and have any wattage from 10 to 80 watts. I figure anything above 80 might as well almost be a gun or use a propane torch. It would be interesting to have 2,3, even 4 different coils in an iron to use differing voltage inputs and have different heat outputs. Another thing that could be useful is clip on LED lighting for soldering irons so you can see better what you are soldering. 

[/ QUOTE ]


You can, utilizing nichrome wire. Many of the Weller soldering pencils are nothing more than a core, covered with fiberglass sleeving such as you find from varflex, a coil of nichrome wire, and another sleeve, and then a metal cover. They do get fancier for the regulated versions.


----------



## Lynx_Arc (Apr 22, 2005)

My guess is finding the right wire and all the parts to fit together may end up costing more than buying a few irons. I wonder how much of a market there would be for a dual voltage soldering iron... 12vdc/120vac. Getting the wattage usable for both voltages could be an interesting task for sure as my guess is the resistance required for 120v would be 1/10 that of 12v, either different wire or 1/10 the length may possibly work to that effect.


----------



## MrAl (Apr 22, 2005)

Hello again,

Yes, it wouldnt be as easy as it sounds for only one piece.
It would work, to wire ten coils in series for 120v
and switch them to all in parallel for 12v but it would
take a *very* special switch. I would guess that two
separate coils would take up too much volume to fit
nicely inside a thin pencil iron.

Another idea is to find a ceramic power resistor, say
about 30 watts with an open center, and run a copper rod 
down the center and thread the end for a screw-on tip.
If the value is sized right it would get hot at 12v.
I dont know how hard it is to get these kinds of resistors
these days however...maybe check the big resistor 
manufacturers sites.

They also make 'heater cones' which screw into a regular
120vac lamp base. They come in various wattages. That
could be a source for the wire. The wire is typically
coiled at about 1/4 inch diameter and then wrapped around
the ceramic cone. You could perhaps unwrap it and 
put taps or whatever, but you'd need a heat resistant
holder such as ceramic. If you know anyone with a kiln
you might pull it off /ubbthreads/images/graemlins/smile.gif
Sure would be REALLY nice to have a 120v/12v iron at about
40 watts.

Radio Shack's dual heat model is for 120v only, with two
heat settings.

I guess another idea (if it hasnt been mentioned yet that
is) is to use a power inverter for 12v to 120v like you
see sold all over the place these days. Small ones that
can power 25 to 50 watts are pretty cheap. This way you
could use your favorite 120v iron too.

I thought about connecting about 12 or so 9v alkaline
batteries in series to get close to 120vdc to power a
normal 120v iron. It would work for a little while
and it would be totally portable. Would be a little
costly to run though he he.

Take care,
Al


----------



## Lynx_Arc (Apr 22, 2005)

What you would end up having to do is wrap one coil an wrap the second on top of it, making sure you don't get tranformer effect from the AC input. If the coils were tightly enough wrapped the heat would transfer from one to the other so you would even run it at perhaps 40w120v, 40w12v or 80wcombined. That would be weird but interesting to have an 80 watt iron that requires two voltage inputs. It could end up having too big and heavy of a coil to be comfortably useful. The voltage inverter sounds like perhaps an easier solution if coils become a mess. I think in the end the best solution would be to either have seperate removable heating elements/coils for differing voltages or seperate irons, that would probably end up being more cost effective. The second best would be to design a soldering station that accepts and converts different voltages and powers the iron with appropriate voltage/current needed.


----------



## CNC Dan (Apr 22, 2005)

you could have one temp. sensor that is in good thremal contact with all the cells( use an aluminium bar), and have it set to shut down early. Then the charger would switch to a lower current for a fixed time to top off the cells that didn't get 'filled' at the highter charge rate.

NiCD cells can tolarate a trickle charge well, NiMH not so much.
Adjust charge rates accordingly.


----------



## MrAl (Apr 23, 2005)

Hello again,

Lynx:
That sounds interesting too. Changeable elements would
be something i would go for. Right now i use two irons,
one for 120v and one for 12v.
The soldering station sounds like something i would
like to perhaps build too...now that you mention it,
if you had a 12v iron you could power it from the car
(12vdc) or using a transformer 120v to 12vac you could
power it in the house too, so the soldering station 
would be mostly a somewhat larger-than-a-wall-wart 
transformer, rated say 4 amps at 12vac. If dc was needed
heck it would probably fly on 12vac to 12vdc using a
simple bridge rectifier rated for the current. This way
one iron rated at 12v would work for both 12vdc and 120vac,
and without needing anything else but a transformer.
How's that sound? 'Course you have to purchase a decent
12v iron first.

CNC Dan:
That sounds interesting but i'd be afraid to trickle
charge my cells because all the manufacturers seem to
dislike that because it might ruin the cells (NiMH).


Take care,
Al


----------



## Lynx_Arc (Apr 23, 2005)

Yea, making a 12vcd iron with a 12vcd converter for the house sounds like an easier idea than a dual element iron. It is easier to come up with a regulator than a boost circuit or alternative coils. The problem may be coming up with perhaps a 4-5amp supply that doesn't add too much to the weight for portability. If you wanted to... you would even make the iron supply a voltage regulated supply.... AND... ooooooo..... build in a nimh battery charger.... all in one gadget. Or you could make 12v devices plug into the base with even a 12v socket for stuff.


----------



## CNC Dan (Apr 24, 2005)

[ QUOTE ]
*MrAl said:*
Hello again,
That sounds interesting but i'd be afraid to trickle
charge my cells because all the manufacturers seem to
dislike that because it might ruin the cells (NiMH).
Take care,
Al 

[/ QUOTE ]

You can do it, but you need to use a *very* low current, and not for too long.

The only other way to equalise the cells is to charge them indivdualy.


----------



## MrAl (Apr 24, 2005)

Hi again,

Lynx:
Oh yes, a battery pack build right into the base
so you could power it from batteries if needed he he.
That would certainly be the ultimate iron /ubbthreads/images/graemlins/smile.gif
As far as the weight of the transformer, it could be
set inside it's own box (like a wall wart only bigger)
with a power cord to plug into the base so that you
wouldnt have to carry the transformer around, just the
base.
The regulation idea is very interesting too -- im thinking
one of the National Simple Switchers to regulate the
power to the iron (5A version). With the regulation
you could also use a pot to vary heat output. Maybe even
have a thermistor to sense temperature for feedback.
That would make one heck of a nice iron!

CNC Dan:
How much current would you use for trickling the cells
and for how long? Remember you'd have to restore the
Ahr's in each cell in order to charge all the cells.


Take care,
Al


----------



## SilverFox (Apr 24, 2005)

Hello Al,

Energizer suggests a constant 0.025C constant charge will keep cells fresh and overcome the self discharge rate of NiMh cells.

I use a 0.1C charge to balance cells in a pack.

Tom


----------



## CNC Dan (Apr 25, 2005)

[ QUOTE ]
*MrAl said:*

CNC Dan:
How much current would you use for trickling the cells
and for how long? Remember you'd have to restore the
Ahr's in each cell in order to charge all the cells.

Al 

[/ QUOTE ]

Look at the data sheet for the cells you are using. They will have charge recomondations, and limitations.

If you quick charge the pack first, and switch to the trickle charge, you only have to trickle charge enough to bring the lowest cell up to full charge. If your cells are well matched, it might not need much at all.


----------



## MrAl (Apr 25, 2005)

Hello again,

Tom and Dan:
Thanks for the ideas, but that's just it...everything
i've read in the past suggests not trickle charging
NiMH cells. Can you's point me to some link i can
read?

Take care,
Al


----------



## SilverFox (Apr 26, 2005)

Hello Al,

Here is some information from Energizer .

"*Recommended Charging Rates*

Today’s trend to faster charge times requires higher charge rates than the 0.1 to 0.3C
rates often recommended for many nickel-cadmium charging systems. Both Figures 18
and 19 indicate that fast-charge rates serve to accentuate the slope changes used to
trigger both the temperature and voltage-related charge terminations. A charge rate of
1C is recommended for restoring a discharge cell to full capacity. For charging schemes
that then rely on a timed "topping’ charge to ensure complete charge, a rate of 0.1C
appears to balance adequate charge input with minimum adverse effects in overcharge.
Finally a maintenance (or trickle) charge rate of 0.025C (C/40) is adequate to counter
self-discharge and maintain cell capacity."

Tom


----------



## MrAl (Apr 26, 2005)

Hi again Tom,

Thanks for the link...

It appears that Energizer likes temperature sensing over
voltage sensing, which is the method i was thinking about
using for my cells.
It also appears that they dont mind 'some' low level
charging (with a timer) followed by trickle charging
at very low rate just to maintain charge. This is
all good news /ubbthreads/images/graemlins/smile.gif


Take care,
Al


----------



## Lynx_Arc (Apr 26, 2005)

I thought of an idea of storing batteries in a holder hooked to a charger with a timer on it. The timer would connect the battery storage module to the charger once a week or two and top them off then disconnect till next cycle. This may require a special charger setup with perhaps remote sensors in the storage modules but could possibly accommodate 100 or more batteries in 25 or so modules hooked up to a charging bus. I would make the battery holders push button so you could remove and insert batteries a lot easier than spring/contacts.


----------



## MrAl (Apr 28, 2005)

Hi there Lynx,

OH yes, i was doing mine similar to that when i 'had' 
two battery packs /ubbthreads/images/graemlins/smile.gif Now im down to one actual pack so
i dont need to do that at least for now.
I had my charger connected to one of those 24 hour
timers. It would turn the charger on for about a half
hour a day to replenish the lost charge, then turn off.
Those timers are available for under $5 these days.

Take care,
Al

PS Having some system problems so i might respond slow for
a while.


----------



## Lynx_Arc (Apr 28, 2005)

The storage idea would be more useful for nimh than nicad for sure. I wonder if and which AA nimh chargers have any drain to them when unplugged with batteries in them. If you found out they didn't drain the batteries when disconnected from power you could just leave batteries in the charger itself and put a cheap $5 timer on them to run once a week or once a day for perhaps 15 mins or less.


----------



## MrAl (Apr 29, 2005)

Hi again Lynx,

I've used the timer idea for a while and it works pretty
well on NiCd's, but i've never tried it with NiMH's.
And yes, the charger drain on the batteries is a good
point as you have to know that ahead of time. My NiCd
charger doesnt put any drain at all on the NiCd's (diode
in series built into the charger) so i know the cells can
stay connected to the charger indefinitely without taking
any charge from the cells. I dont know about my NiMH
charger however -- i've never tested it and the manual
i think says to take the cells out once the charge is
complete...i dont know if that's because the cells get
drained or for safety reasons or something.


Take care,
Al


----------



## Lynx_Arc (Apr 29, 2005)

Most likely they are concerned about overcharging the nimh cells. If power were to go off/on via a thunderstorm etc it could be possible for a charger to lose its mind and overcharge and damage the battery perhaps. It could also be that even when completely charged some chargers have a slight trickle charge on cells or leakage or something as since they charge when you insert a cell there has to be circuitry to query the battery and detect if the charger should run or not. 

With all the super fast <1 hr chargers out there I really think keeping cells topped up constantly isn't needed. Perhaps once every 2 weeks would be fine for most people on topping cells off.


----------



## MrAl (Apr 30, 2005)

Hi again Lynx,

Oh yes, now that you mention it my new Li charger has about
15k across the cell which is used to measure the voltage.
This means about 280ua drain at 4.2v, but of course with 
those cells i never leave them on charge because i dont
trickle charge Li-ion's.
I guess if i were to construct the NiMH cell charger i'd
use a higher value set of resistors to measure voltage
(like 100k or something like that) to make sure there
wasnt too much drain even for days.

I guess if you want to charge every 2 weeks you'd have to
find a better wall timer that had settings like that.
The cheap ones all seem to be 24 hour timers, where you
can have something turn on once every 24 hours but you cant
set if for one or two weeks.


Take care,
Al


----------



## Lynx_Arc (Apr 30, 2005)

I may have to look around at the closeout stores to see if some of the digital timers there have settings more than 24 hours. I suppose you could make your own timer circuit if you were adventurous. If you could dissasemble a 24 hour timer perhaps the countdown mechanism could be modified so it either counts down slower or has a larger pool to base countdowns on... perhaps a larger cap or something depending on the design. With the ease of just pluggin in battery packs to charge them vs having to remove and seperately charge single cells in lights I am toying with the idea of a subC or C lantern with a 4-5 cell pack to do away with the size of the battery holder, springs etc. Imagine having to charge 15 subC cells 2-4 at a time on an 18v drill motor. That would be a pain in the posterior for sure.


----------



## MrAl (Apr 30, 2005)

Hi again Lynx,

Yes, that would be a pain, and you gave me another idea /ubbthreads/images/graemlins/smile.gif

Instead of purchasing ONE timer, purchase TWO timers,
and set one for say one hour per day and plug that into
the second timer which is set for 4 hours per day.
The result would be the first timer would come on once
every 6 days for one hour. Setting the second timer
for three hours a day instead of four would result in
the first timer coming on once every 8 days for one hour.
Neat huh? he he.
Now all i need is a second timer to try this with ...hmmm...

Take care,
Al


----------



## Lynx_Arc (Apr 30, 2005)

I got two timers.... just dont tell the women about two timing they may misunderstand you. /ubbthreads/images/graemlins/eek.gif You would have to make sure the timer was set in such a way you get the complete runtime needed to charge in one session instead of splitting it up in two sessions.


----------



## MrAl (May 1, 2005)

Hi Lynx,

He he /ubbthreads/images/graemlins/smile.gif

I dont think it would matter 'that' much if the cycle got
split up into two sessions instead of one, which i think
would eventually happen as the timers eventually get
out of sync, unless of course you check them every
three months or something.
Usually the charge put into a cell can be split up
into two sessions without any problems.

Does it bother you that that might happen?

Take care,
Al


----------



## Lynx_Arc (May 1, 2005)

well if you were trying to keep the batteries up to 100% and you got half a charge on them twice in a month they would probably be less than optimal, sort of like you only recharged them once in a month and let them sit for a month instead of 2 weeks.


----------



## MrAl (May 1, 2005)

Hi again Lynx,

Actually, if you go through the logic of it... if the
first timer is set for 4 hours per day and the second for
two hours per day, the idea is to have the device (charger)
turned on for two hours every 6 days, which would work
until the two timers got out of sync. Eventually, the
second timer would come on as expected but then the
first timer would shut it off prematurely after say 1
hour instead of the planned 2, but then 20 hours later
the first timer would again turn it on and since the
second timer is still 'on' the device would get it's 
second half of the run time (the second hour).

This means normally the device would get 2 hours every
6 days but when the two timers were out of sync it would
get a partial run for whatever time period the first
timer allowed and then 20 hours later it would get the
remainder of the run time regardless of what fraction
the sync'ing allowed at that point. I would think there
would be a slight mis-sync all the time, so this run cycle
would start out at 2 hours for quite some time followed by
a dual cycle like maybe 1.9 hours + 0.1 hours, then
1.8 hours + 0.2 hours, etc., until the two timers became
sync'd again.

In short, the average run time over a period of 48 hours
would be the same as if the two timers were perfectly in
sync all the time.

Make sense?


Take care,
Al


----------



## Lynx_Arc (May 1, 2005)

In time it will............................make sense.
OOPS I think my first timer shut off my train of thought half way perhaps I will figure it out tomorrow. /ubbthreads/images/graemlins/yellowlaugh.gif
If you did 3-4 timers you could top off lithium ion batteries once or twice a year also.


----------



## MrAl (May 2, 2005)

Hi Lynx,

Oh yeah, ha ha, that would be neat...having it come on only
once per year.
The way my current timer is set up, the smallest time
period you can set it for is a half hour (30min) so
if i were to set the first timer for 1/2 hour and the
second timer for 1/2 hour the longest period i can get
would be 48 days. I guess a third timer coming on only
once every 48 days would give me 48 times that
(48 times 48 days or just over 6 years?) ha ha.
I guess that would be long enough for most things /ubbthreads/images/graemlins/smile.gif

I guess this means two timers would do a 'once every month'
cycle too, which would be nice i think for NiCd's or
maybe NiMH's.

Take care,
Al


----------



## Lynx_Arc (May 2, 2005)

well when they get batteries with lower discharge you will be ready for that. 

I just picked up an SLA headlamp setup over the weekend and the battery holder has a built in charging circuit. I was given a 12v 400ma adapter but the battery is 6v and I tried it and at a 6.2v battery voltage the circuit wanted to push 900ma into it and the no load voltage was about 7.6v. Does this sound a bit too high for a 4.5A/hr ~6v SLA? 
I may try to get more of these as the belt pack is nice and the price is such I could probably offer them to CPFers.


----------



## MrAl (May 2, 2005)

Hi Lynx,

OH yeah, when they come out we'll be the only two CPF 
people ready /ubbthreads/images/graemlins/smile.gif Really, i cant wait!

SLA, well i think 2.4v is the cell max float charge, so
that brings you to 7.2v max, but i think i'd use a max
of 7v myself as i certainly wouldnt want to ruin my
battery. For 4.5 Ahr a max of 450ma would be comfortable,
but it's been a while since i looked at the spec's for
these...perhaps you can find the manufacturers site
and check the model number for exact specs...i'd bet
they have recommened max charge rates and stuff like
that.
My big SLA comes with a 700ma charger -- although i forgot
the exact Ahr rating now -- it's must be around 20 Ahr.
The manual says not to charge with a bigger wall wart too.

How does it work out in practice to actually have a wire
running up to the headlamp ( i have a smaller one that
uses internal batts) ... does the wire ever get in the
way or anything?


Take care,
Al


----------



## Lynx_Arc (May 2, 2005)

I bet I need a 7v ac adapter for it. I am beginning to like SLA myself. You don't have to charge them very often as the batteries are slow to self discharge and usually that have a decent capacity for the price you invest. Nimh and nicad C/D cells are about the only thing that can compete well with them and cost similarly and suffer from self discharge.

I tried the lamp with the wire and it has clips on the headband you can move the wire all away around the headband out of the way so it doesn't really get in the way. If you use a belt and mount the SLA on your back it would probably be most of the time unnoticable. 

I am beginning to warm up to the idea of SLA based lights. Not having to worry about batteries draining down every 2-4 weeks is nice and not having to pull them out and cycle them through chargers is nice also. 

3 of my headlamps are 6v and have the same socket/connector combo on them, two have externally belt mounted packs so I could essentially swap them around. One has a 4AA holder mounted into the harness with a cord on it so I could pull that cord out and attach the SLA or 4D pack if wanted. 

Perhaps more people will get interested in corded SLA based headlamps... a dual 3watt luxeon headlamp could be fun or 3 3watters off a 12v SLA headlamp would be pretty bright. You could also plug your drill into the same pack so you could have a lighted drill setup.

Just tracked down the website that has most of the headlamps I picked up on it. Optronics nightblaster 
I got the following:
HL-40CS similar to HL-403RG (3 bright red LEDs)
HL-700C (under HL-7000) 
HL-7400 (still in plastic pack in brand new condition)
HL-7200 Looks like that with halogen/LED combo
HL-? Looks similar to HL 7400, HL-7200 but had optic over LED and seperate battery holder for 4.5A/Hr SLA cell.

I hope to be able to procure more of these headlamps and hopefully some of the other types listed on that page also.
I couldn't find any info on the SLA charger and light combo, it must be a discontinued item as a few of the others may also be.


----------



## MrAl (May 3, 2005)

Hello Lynx,


I checked my Electrical Engineers Handbook and it shows
a typical LA battery cell going as high as 2.60v, but
im not sure if that would apply to the newer SLA type.
If this is true for your batt too you could go as high
as 7.80v, but im not sure if i would do that if it were
my battery, unless i made some measurements from charging
with about 450ma and see how long it takes to charge, etc.,
and watch the voltage increase. I'd definitely check
the specs of that exact battery before doing anything.

I checked out that site but couldnt find any prices on 
the headlamps they had there.
I have a headlamp that looks just like the 7800 but has
the headband of the 7700 and actually has 8 white LEDs.
The 4 in the center turn on for 'low' and all 8 turn
on for 'high'. I only paid $10 for it but i think it's
a chinese remake or something. Quite sturdy however, and
the switch is pretty nice too.


Take care,
Al


----------



## Lynx_Arc (May 3, 2005)

The SLA looks to be new and came with a full charge on it.
I am going to check back and see if I can get more headlamps and/or these SLA battery pack setups, I think they would be neat for modders to use.... perhaps even make a corded light with a high output halogen bulb. About how much current can a 4.5 amp/hour sla put out reasonably compared to perhaps a 6v nimh pack?


----------



## SilverFox (May 4, 2005)

Hello Al,

Your EE Handbook must be referring to a maximum voltage used during charging. PowerSonic and Shulze consider a full charge when the cell reaches 2.42 volts. The Schulze uses a timer that shuts things down after 3 hours, but there is a trickle charge mode on the more advanced units. It pulses a charge to keep the voltage up. I believe the spike of the pulse is right at 2.6 volts.

PowerSonic's advanced management chargers shut the charge down when the cell reaches 2.42 volts, then turns it back on when it drifts down to 2.3 volts. They believe this method is superior to leaving the cell on a steady trickle charge.

Tom


----------



## MrAl (May 4, 2005)

Hello again,

Lynx:
With the SLA's i think the max current draw has to be gotten from
the manufacturer's battery specs, but one battery i know of offhand
is the BP-50, which is a 6v 7.2Ahr SLA and they spec 3.0 amps max
at 50 degrees C. Except with my car battery, i've never tried to
test one under very heavy loads so i dont have much to offer here
for batteries with unknown manufacturer. I had one that came with
a real cheap flashlight that you were lucky if you could get
1 amp out of it  I chucked those out, as they also didnt hold
a charge very long either.
On the other hand, my jump starter battery has to handle very high
current loads (100+ amps) for short periods so i guess it depends.
If you really need to know and cant find specs perhaps you can apply
a variable load and try increasing load current and watch voltage
drop.
If you're talking about AA size NiMH's, i think id go as high as
1.5 amps but probably not too much higher. The batteries will
take this current and the power diss when charging at 1 amp CC
is about the same. I'd be happier with 1 amp max though, but i guess
it depends on how bad you want to run something with them more than
anything else 

I'm *sort of* into SLA's too, as they can be used for high current
stuff and they have high Ahr ratings i like which isnt found in
smaller NiMH's and the like, and i think the price is better per
Ahr too. I might be interested if you can get lots of 6v 'ers as
that size is nice also. As long as they are new batteries they
should last a while.
Chargers are easier to build for SLA's too...perhaps even a bit
boring when you think about it /ubbthreads/images/graemlins/smile.gif

Tom:
Yes, the handbook was referring to the voltage near the end of the
charge cycle, but i'd still feel more comfortable with the 2.4v
max myself.
That sounds like an interesting charger...perhaps i can read up more
on that particular type.


Take care,
Al


----------



## Lynx_Arc (May 4, 2005)

I was thinking about all those high power maglights people have and how short of runtime they get off AA cells. Someone could make one of those with a DC input adapter and use a corded SLA with possibly a small regulator to power it longer and then use the AA or internal battery when they don't want to mess with the SLA. I suppose you could even make a mini spotlight head with some sort of handle similar to a maglite head also. I kind of like the idea of belt carried batteries with a cord better than a spotlight with everything self contained due to the bulkiness and awkwardness of a huge... *blob* of plastic and stuff with potentially oversized reflector that throws for 5 miles when a few blocks is all you need to do most of the time.

Perhaps someone will design a well heat sinked headlamp for high output halogen bulbs that doesn't brand ones forehead in pain after 3 minutes of runtime or melt the plastic in the case all over them in 5 minutes of high output.


----------



## MrAl (May 5, 2005)

Hi again,

Oh yeah, good idea again /ubbthreads/images/graemlins/smile.gif
I guess what i DONT like most about those huge Maglights is that
they are too big for me to carry around easily. On the other hand,
a head + a 6v SLA wouldnt be 'that' bad, especially if it was in
the form of a headlamp with a cord to the belt batt pack.
My current HLamp has 4 x AA's and even that's a little heavy.

I gave up on those high powered halogens after one experiment:
I made a special holder and would allow it to fit right in the
end of a nice finished alum tube, about 1 inch diameter. Hooked
it up to some volts, and geeze, that dang thing got hotter than
anything i'd ever seen in a light before! Also had a sort of
orangish tint i didnt really like for most lighting applications
i would use it for (yeah ok, a back lighting mood light, but
who needs it). After a few minutes the heat started to heat up
the tube too and it wasnt the lightest gauge metal, and it wasnt
that small. After say 10 minutes it would heat the whole thing up
so bad you wouldnt be able to hold it. I've since then given up
on incand for most of my lighting, after all some 97% of the input
power is converted into heat and i dont like the idea of carrying
a power resistor around with me /ubbthreads/images/graemlins/smile.gif
I like the whiter light of the LED's too for almost everything i 
use a light for.


Take care,
Al


----------



## Lynx_Arc (May 5, 2005)

yeah, need to make an SLA drill, LED light, CD player, drill combo. If you adapted all your lights with an input jack for SLA operation you could all but do away with normal batteries.


----------



## MrAl (May 7, 2005)

Hi again,

Yes, sounds cool! One power source for everything.
My drill should run on two 6v SLA's, but i bet it wouldnt
be too bad on just one also. That would be very easy to
carry around on a belt too. My 12v jump pack is so big
it has it's own handle, but it does pack a lot of charge
i guess. It's not as convenient though as the 6v'ers would
be.
I've seen lots of the 6v SLA's go into saftey power outage
spot lights, and i've seen them dry up inside...that's about
the only thing i dont like about them...but then if i used
one for my own purposes i wouldnt have it on constant charge
either, which is probably what dries them up.

Take care,
Al


----------



## Lynx_Arc (May 7, 2005)

I think that keeping SLA on constant trickle charge slowly does that. Has anyone ever posted the discharge rate of SLAs? I bet it is rather low compared to nimh and nicad cells. I have seen a lot of talk about people leaving SLA based lights on constant float charge and to be honest I am not sure it is really needed once you get a full charge. 
Imagine someone with a cell phone hooked up to a belt pack SLA cell..... days of runtime.... can you sleep me now.... err hear me sleep.... ZzZZZzzz.


----------



## MrAl (May 8, 2005)

Hello again,

I dont know if anyone posted that info. You're right in
that it must be slow, because when i dont use my big 12v
SLA even for a long period of time it doesnt take very
long to reach the end of charge (as shown by LED indicators)
after putting it on 700ma charge.
I guess i could monitor this process more carefully in order
to determine just how long it sits before needing a 700ma
charge for say one hour.

My EE Handbook gives non specific rates from 15% per month
and down, with the purer lead based batteries being the
best.

Yes, the SLA's offer very long run time for things we
dont normally think would be running that long...that's
why i like them too.

I dont keep mine on float either. From what i've seen
it doesnt need it anyway as the self discharge is so low.


Take care,
Al


----------



## Lynx_Arc (May 8, 2005)

I am guessing the 15%/month is for non sealed lead acid batteries but even that sounds high I suspect. It is too bad they dont make SLA cells in C/D size, they may be nicer to store in lights than nicads and the lower discharge and possibly cheaper price than lithium technology.


----------



## eluminator (May 9, 2005)

Yep, I appreciate the low self-discharge of lead acid batteries. The rate apparently depends on the quality of the construction. Some manufacturers that use high purity lead, etc. say theirs only need topping off once a year.

They do have disadvantages though. Their energy density seems to be quite low. I wonder what the mah rating of a SLA D cell would be. I guess they would be quite heavy also.

Another problem with lead acid, sealed or otherwise, is that they are only happy when kept fully charged. If you store a lead acid that isn't fully charged, it will lose capacity permanently due to something called sulphation. So their shelf life is low unless you periodically top them off. That's what I've been told anyway.

And then there is the disposal problem. I guess you can toss NiMH in the garbage. Those with lead are supposed to go to the recycler.

You just can't win.


----------



## Lynx_Arc (May 9, 2005)

I will take the minor problems of lead acid over having to top off nimh/nicd once or twice a month. I figure a decent SLA you top it off maybe twice a year while the nickle metal batteries you would have to top off perhaps 12-24 times a year. As for recycling I have decided to recycle all my batteries, there is a recycling center at a walmart next to my church that takes all batteries so I fill up a container with them and take them there when it gets full. I didn't know they took alkalines and heavy duty and watch batteries too. If you had enough lead acid batteries they probably would pay you a pittance for them as the metal recycling place pays $1 each for car batteries for the lead in them.
When you are dealing with larger batteries having them a little heavier isn't as big of a deal, just get out the workout tapes and rip up the muscles a little more. Perhaps some of the flashaholics need a little arnold in them and stop relying on lithium batteries to save their muscles...


----------



## MrAl (May 9, 2005)

Hello again,


Lynx:
Yes, that 15% per month was for a special LA type they might not even
make anymore.
It would be interesting to be able to get a D size SLA, but then i dont
use those sizes much anyway myself...now AA size i'd be interested in /ubbthreads/images/graemlins/smile.gif
And i agree that the shortcomings dont outweigh the advantages at least
for what i use them (SLA) for. The price is really lower for SLA, which
is sometimes a very important factor. For what i paid for my SLA if i 
bought NiMH cells i'd probably end up with a lowly 2Ahr battery instead.
Also, how many NiCd's (or NiMH's) would it take to start a car? 

eluminator:
Yes there are disadvantages which ever cell you buy, but price is often
the determining factor. I dont think their energy density is that low
really, and might even be above some of the older NiCd's, but they seem
heavy because you usually get a lot of battery in one physical product.
Perhaps the newer NiMH cells beat the LA by some 50%.
Yes, i like being able to toss NiMH in the garbage, which is probably
where they should be anyway /ubbthreads/images/graemlins/smile.gif (ok, just kidding).
With the sulphation problem it isnt that bad in the SLA's because you
dont have to top them off that often...as mentioned about once or twice
a year. Of course when you buy one you have to make sure you charge it
by a certain date too...which is a little strange...but then you usually
intend to use it soon enough if you purchase it.


Take care,
Al


----------



## Lynx_Arc (May 9, 2005)

I like SLAs because you can put them in stuff and forget them for months and come back and use them and typically they haven't lost any noticeable charge. I have several lights I would store in places around that I wanted to put rechargable batteries in but don't want to have to remove the batteries once or twice a month to recharge them so they will be usable in an emergency. I instead have cheap 2D alkalines in lights which gives me enough light to find my other lights stored near my charger. With SLA cells I could have nicer lights in more places without having to maintain them but a few times a year. Nimh/nicad are nice but if you had to pay someone $10 an hour to maintain lights with them in them you would either end up buying plugin wall nicad lights or go with lithium/alkaline cells instead. This is where SLA could shine. Perhaps they could make some roundish SLAs that were 2D cells long that would allow you to drop in a 6v SLA into a maglight and change the bulb or put a luxeon in it.


----------



## MrAl (May 9, 2005)

Hi Lynx,

That would be cool, for sure, but dont SLA's have an
orientation issue? Dont they have to be kept right-side-up
in case they decide to vent or something?
I never let my big 12v SLA lie on it's side and i really
wouldnt want it to be upside down for very long.

I never really looked very well into this issue however...

Take care,
Al


----------



## Lynx_Arc (May 10, 2005)

If there was an issue with certain sides being up I am sure all these SLA based spotlights would be have stickers on them to only use them and charge them and sit them down... this side up.


----------



## MrAl (May 10, 2005)

Hi again,

Yeah, that makes sense /ubbthreads/images/graemlins/smile.gif

The two chinese lights i picked up a while back had
SLA in them too, but they werent very good batteries.
I guess that means some of them can be tossed around
without any problems. Seems i remember reading something
in my Jump pack manual about this 12v SLA however, about
keeping it upright...I'll have to try to find the manual.

If you find any good priced SLA's let me know if you can.

Take care,
Al


----------



## eluminator (May 10, 2005)

[ QUOTE ]
*MrAl said:*

It would be interesting to be able to get a D size SLA, The price is really lower for SLA, which
is sometimes a very important factor. 

[/ QUOTE ]

I do like the price. The SLAs I buy on the internet are cheaper than dirt, although the shipping costs more than the batteries. 

I wish I could use SLA in my 4 D cell radio. Those D cell NiMH are pricey, and I already degraded the capacity of one of them through over-discharge. I learned my lesson and now check the battery level display every day.

Unfortunately the higher voltage of the SLAs would present a compatibility problem. Maybe the reason they don't make SLA in D or AA cell sizes is that the voltage isn't compatible with other cells, and therefore not compatible with the equipment that uses the other cells. So there isn't much benefit in making them the same size as other cells.

[ QUOTE ]
*MrAl said:*
Also, how many NiCd's (or NiMH's) would it take to start a car? 


[/ QUOTE ]

Heh heh. /ubbthreads/images/graemlins/smile.gif You know the answer to that one. It would take one battery of course, with nine or ten cells. I guess it would be twice as big as a lead acid battery. For sure it would cost a king's ransom. I suppose a battery that expensive would need to have each cell monitored to prevent voltage reversal. I think I'll stick with my diehard for the time being. /ubbthreads/images/graemlins/smile.gif


----------



## SilverFox (May 10, 2005)

Hello Lynx Arc,

I would suggest that you properly dispose of your NiCd and NiMh cells that you are having to recharge twice a month. They are suffering from high rates of internal discharge and are beyond the end of their useful life. /ubbthreads/images/graemlins/smile.gif

It is true that NiCd cells self discharge, and that NiMh cells have a higher discharge rate than NiCd cells, however let's take a closer look at this.

NiMh cells have a higher discharge rate than NiCd, so let's concentrate on those. I have several emergency lights scattered around the house. They will typically run for 18-24 hours on a set of batteries. I have NiMh cells in them and have been checking this self discharge rate out.

The battery manufacturers sometimes state a self discharge rate of 1.5%. This seems to be a maximum figure. I have checked several "quality" brands of cells and find that 0.7% (and sometimes lower) is the actual rate for newer cells. As cells are used, their self discharge rate can go up, so keep in mind that these results are for cells that are only a couple of years old. Also keep in mind that abusing cells will damage them and the damage will manifest itself in higher self discharge rates.

The self discharge rate is based on the amount of charge left, so it is not a simple regression. The first day you start out with 100%, day 2 you have 99.3%, day three you have 98.6% and so on.

Here is the real world comparison. My standby lights have a run time of 18+ hours on a full charge. After 90 days of self discharge they are down to 9.6 hours of run time. After 180 days of self discharge they are down to a little over 5 hours of run time. After 360 days of self discharge, they are down to 1.75 hours of run time.

In my humble opinion, this is acceptable. I usually recharge the cells in those lights every 3 months, but if I happen to miss a cycle it is no big deal.

Understand that I have measured the results at 90 and 180 days. The 360 day projection is calculated.

As far as starting your car goes… The GP 2/3 A 1100 mAh NiMh cells are capable of 15 amps. Keep in mind that this is the same physical sized cell as CR123’s. There are also Sub C 3200 mAh NiMh cells that are capable of 40 amps. So if I need 100 amps to start the car, I would put together a pack with 10 cells in series and parallel 3 of these. That would give me 12 volts and 120 amps. That should get the job done… /ubbthreads/images/graemlins/nana.gif

Tom


----------



## eluminator (May 10, 2005)

I was looking at Power-Sonic's site to see if I could find a 6 volt battery that I could jam in the cavity where my 4 NiMH D cells sit. No such luck.

Comparing their 6v 7ah battery with my NiMH 5v 8ah battery (4 D cells), I find the SLA weighs twice as much and takes up a little more than twice the volume. Actually the volume efficiency is worse than that because I'm using the size of the solid rectangular cavity in the radio. Of course D cells are round and so some of the cavity is just air.

Still the low cost of SLA and the apparent resistance to damage by cell voltage reversal make them attractive. I already have an SLA charger so if I could get an SLA that would fit in the radio, I'd try it.

I'm assuming the SLAs aren't normally damaged by voltage reversal because I haven't heard of it. Maybe I'm wrong. Now that I think about it, I always shut off my SLA powered spotlight before the voltage drops by a third. Maybe that's why I haven't damaged an SLA yet.


----------



## Lynx_Arc (May 10, 2005)

Silverfox... that all makes sense, I haven't paid a lot of attention on nimh self discharge but I seem to be recharging them about once every 6 weeks or so while using them perhaps I am guessing 40% down in capacity so that probably translates to 50-60% loss. If you can wait 3 months and maintain 80-90% of capacity it would be fine but apparently after that period of time you are closer to 60% which cannot compete well with the SLA self discharge which appears to be I am guessing in the rate of perhaps 1%/month.

Eluminator- A 6v SLA varies but most 6v devices should be able to tolerate the higher voltage fairly well as 4 alkaline D cells can output close to 1.7v/cell or up to 6.8v which is inline with a freshly charged SLA, which runs around there but typically likes to sit around 2.1v/cell or 6.3v from what I have measured. I haven't experienced cell reversal on any lead acid batteries but I am guessing it does happen to them somewhat as I have had weak car batteries that had a *dead* cell you could find by measuring between the water holes (not sealed battery).
If you are going by weight and capacity/volume SLAs stink, but their self discharge and ability to run multiple cells more robustly and charge them in concert is their advantage.
Not many standard devices that alkaline batteries can easily power are fitted for SLA use but if the device has a DC input jack to it you could wire an SLA into that port by making a cable with proper plug on it and unless you are moving it around a lot and don't like hauling a seperate external battery it would work well. I see the SLA jumper/charger/power output gadgets gaining ground based on this same idea... portable rechargable power source with more ease of use.

MrAl- I am going to check with my source I picked up the headlamps from, he told me he had about 2 tons of SLA batteries (apparently bad) that he was trying to find a place to recycle them at. It may take me up to a month to get ahold of him. I am thinking most of his SLA either are in spotlights or pulls from broken lights so the size would be accordingly. I have 2 SLA cells I bought bare and a third one in a spotlight. I paid $4 for the 6v lantern SLA battery (springtops) and $3 for a 12v 3ahr SLA at walmart with charger included I have yet to figure out what to do with.
When I was a kid I was given 3 SLA 12v cells by my dad they were computer backup batteries they pulled and were slightly weak but I put them in a box and made 3 voltage regulator circuit using LM309 chips so I could run my stereo which takes 9vdc and other battery powered devices. I even put in a 12v charger circuit, probably was charging them too hard as I didn't know a ton about chargers and electronics then.
The batteries lasted about 4-5 years and then started getting too weak. I found the weight of the 3 batteries discouraged me from toting them around a lot but having to buy 6D cell alkaline batteries every few months for my radio offset that to the most extent.
Perhaps someone can figure out a capacity/weight/volume ratio for various cells and figure the volume of standard battery sizes like AAA/AA/C/D/6v lantern. My 6v lantern SLA is 6v 5Ahr and I am guessing 4 F SLA cells could be made to do about 12Ahr or so in nimh formulation.

If they got D cell nimh down to about $3 each or less a 6v pack of 5 cells (equivalent to SLA) would be $15 which is perhaps nearly the same cost as a decent 6v SLA.
I have seen small SLA batteries now and then but the price of them and odd voltages discouraged me from buying them. I could have gotten dozens of 10v SLA for $1 each.. camcorder closeout batteries but I don't find that off of voltage useful. I am guessing it was a 5 cell or 10.5v battery and would probably run 9v stuff ok.


----------



## eluminator (May 10, 2005)

I used to notice that when my car battery was on it's last legs, it would lose one cell. I could tell just by looking at the voltage gauge on the dashboard.

I don't know why the one cell fails though. I guess I figured it just shorted out.


----------



## Lynx_Arc (May 10, 2005)

since there are lead plates in the cells to conduct and react with the sulfuric acid most likely the plates wore out and/or were not deposited back correctly after multiple recharges. 
I have a feeling cell reversal does effect lead acid batteries but since the plates are thicker usually the effect takes longer to harm them than other batteries.


----------



## MrAl (May 11, 2005)

Ready

Hello again,

eluminator:
Yes, the different cell voltage probably has a lot to do with the
compatibility with other cell chemistries, but as Lynx pointed out
a 6v version wouldnt be bad (that is, to emulate 4 cells in series)
but then i guess they'd have to make one for 4xAAA, another for 4xAA,
another for 4xC, 4xD, etc.
And yes, he he, i'd hate to think of the cost of a car batt made from
all NiCd's or NiMH's and even if they could handle the high current
which car batteries are specifically designed for.

Tom:
Some car batteries have very very high cold cranking amps rating, so
perhaps you'd like to estimate the number of cells required and how
much it would cost to purchase them /ubbthreads/images/graemlins/smile.gif Would be interesting to replace
the battery with better types, but i know it would be really expensive.
Nice side effect would be it would then be a 'deep discharge' type which
would be useable for many other purposes too!

eluminator:
I never checked the cell reversal damage of a SLA, but i had one rated
for around 4Ahr one time that wasnt quite up to par (about 3Ahr maybe)
and after not charging it for about a year it died completely. Makes
a darn nice paper weight though /ubbthreads/images/graemlins/smile.gif

Lynx:
My batteries seem to discharge quite a bit too, like 3 percent i think.
With most of mine i have to charge about once per month or so or else
there wont be any power left when i go to use them. This is one of
the reasons i started moving to Li-ion for some things...i dont have
to worry as much about self discharge. If it wasnt for that, i'd use
NiMH in everything i think. SLA, when possible, is just so hard to beat
though!
If the initial cost of Li-ion wasnt so high i'd probably
adopt everything i have to that technology, with SLA for
the higher current requirements.


Take care,
Al


----------



## Lynx_Arc (May 11, 2005)

MrAl- since most of my nimh are in LED lights I don't notice them being down after over a month until I do something like read with them or on rare occasion take a long walk somewhere.
There is so much light around the house and the immediate neighborhood I have to put towels and blankets over the window just to sleep at night. I also have fluorescent nightlights because my roommate doesn't really take to flashlights much and likes to leave lights on all night if I forget to turn them off. Luckily I put two nightlights.. one 1.6watts the other 3watts fluorescent and leave them on instead of 20-25 watt CFL or 75 watt incans.

One nice thing about SLAs is you dont have to fumble with removing and reinserting batteries to charge them. Lithium are nice but rechargable lithium cells of any size comparable to SLA and C/D get rather costly and I have heard rumors they don't last but a few years in service. 

I dont see 6v/12v 4+Ahr rechargable lithium cells in the future anywhere near as cheap as an SLA and nimh/nicd is a pain in the posterior for low maintanence stuff, that is why most people use alkaline batteries where possible they don't like to mess with chargers and self discharge in that gadget you use twice a year.


----------



## SilverFox (May 11, 2005)

Hello Al,

The Sanyo HR SC 2600's have been tested to 10 second bursts of 100 amps and would probably start most cars. I believe they run about $5 each. If you need 200 amps, you could get two, ten cell packs.

The problem with NiMh cells is not starting the car, it is keeping the batteries charged between starts. Cars are set up with a constant trickle charge that is better suited to SLA.

Tom


----------



## Lynx_Arc (May 11, 2005)

The constant trickle charge is definately a problem, even for the Lead acid battery in the car as from what I have noticed over the years deep discharges are followed by fast furious recharging by default via 100 amp alternators instead of a slow charge. I figure they could get around the trickle charge problem using nimh technology but unless the price were brought down inline with lead acid technology in similar capacity range it isn't worth messing with designing a more suitable charging system to help protect the nimh or nicad cells from damage via constant high output trickle charge and cell reversal from deep discharges may render packs of batteries impotent within perhaps weeks of use by cell reversal damage where lead acid is more resistant to such damage IMO.


----------



## MrAl (May 11, 2005)

Hello again,

Lynx:
Yes, usually LA's are built right into the device so you dont have to
remove them to charge, but i did the same with an AA sized Li-ion too,
in my small Luxeon flashlight, where i have two slots in the light body
where you connect to the battery terminals via clipleads to charge.
You dont have to bother with taking the cell out every time to charge
and charging only takes about 2 hours.
I dont see rechargable li's being too cheap in the future either, which 
is too bad really.

Tom:
Oh, 100 amps, that's pretty good, but im wondering what the internal
resistance is now...even a small R like 0.1 ohms (10 cells in series)
would drop 10 volts at 100 amps, so i wonder what the cell voltage
drops to at 100 amps?
Sure, i wouldnt expect to exactly 'replace' the car batt with NiMH's,
but if there were any real worthwhile advantage i'd sure figure out
a way to have them charge via the alternator -- even if it meant a
special regulator. From what it sounds like, even if the cells could
support BOTH the current AND the terminal voltage required it would
cost something above 100 dollars to construct a car battery. Im not
sure that would be something i would want to do, unless there were some
really big advantage.

Lynx 2:
Yeah, but as i was saying to Tom if there was any really good advantage
im sure we could design a regulator system to handle it in the car...
but is there any real advantage...maybe some weight advantage, but is
it enough to warrant such a project? hmmmm....


Take care,
Al


----------



## eluminator (May 11, 2005)

I'm thinking the NiMH car battery must be expensive. Otherwise the car manufacturers would use them. They do the darndest things to save a few ounces. The car owners would need to be able to get a replacement battery easily.


----------



## SilverFox (May 11, 2005)

Hello Al,

It looks like they drop down to about 0.9 volts at 100 amps.

Check this out. 

Think of what we could do with a flashlight that requires 100 amps...

Tom


----------



## Lynx_Arc (May 11, 2005)

dont put a 100 amp flashlight in the hands of an idiot.. could be dangerous. Hey mom I just melted my football helmet to my face can you help me? YIKES!

Added-
I came across something today I almost bought. Harbor freight has 12v float chargers (maintainers) for $6.99 that
supposedly work for 5-125v SLA batteries. These are not for charging batteries but to keep them topped off without drying them out and damaging them (supposedly).


----------



## MrAl (May 12, 2005)

Hello again,


Tom:
Oh yes that looks pretty good, but i'd also wonder what
happens with age, after all, if you have 10 cells in
series and the voltage drops to 0.9v per cell that's
only 9v left to start the car with. It might work.
Sure would be interesting, but then i dont think i would
go the expense to find out -- i guess it would cost about
50 bucks to purchase that many cells, and then there would
be a few practical issues like how each cell connects
together (have to be a good, solid, heavy gauge connection).
From what it sounds like however i bet it would jump start
a car that already had a battery in it...

Lynx:
Geeze a 100amp flashlight he he. That should be pretty bright /ubbthreads/images/graemlins/smile.gif
12v float chargers...wonder if they have any 6v ones too..


Take care,
Al


----------



## Lynx_Arc (May 12, 2005)

MrAl
I didn't see any 6v chargers at all at harbor freight. I have
a 6v/12v charger that I think even has an adjustable lower scale down to 100ma that should be able to charge most SLAs I figure. I also stumbled across a 12v nicad drill battery pack at BigLots for $5.99 probably containing 10 subC cells.

Somehow I don't think nimh will work well for a car battery. I am betting that a car battery takes more *topoffs* or slight recharges than a nimh can. Think about it, starting a car twice a day for 5 days a week 50 weeks a year just working a job adds up to 500 times the battery is slightly recharged. This doesn't include shopping at 5 stores, going to a movie and other things. If nimh can be recharged 2000 times in this fashion it could work as a car battery but somehow I hesistate to think nimh is robust in this fashion.


----------



## MrAl (May 12, 2005)

Hi again Lynx,

You know, that was my gut feeling too /ubbthreads/images/graemlins/smile.gif
Im sure it could be done, one way or another, but i see
NiMH as not working quite as well at 100 amps as for lower
currents, whereas the car battery is designed just for that
VERY purpose -- to put out tons of current for short periods
and then charge back up. NiMH would probably make a good
jump pack though i guess...as long as you didnt mind 
that once a month or so maintenance charging (UhGGG!)

You know what's kinda funny...if you own lots of NiMH cells
your spending a lot of time doing maintenance charges he he.

What you were saying about the Li-ion's only lasting a
few years bothers me too, as i've read it's around
3 years regardless of use. Im hoping it's longer, but
i guess i'll find out with my small flashlight. I estimate
that i'll be recharing it between 4 to 6 times a year, which
after three years is no where near the max number of cycles,
so i'll be finding out first hand if they really die
after 3 years or if they just gradually die down over
that last year.


Take care,
Al


----------



## Lynx_Arc (May 12, 2005)

I almost wonder if Lithium rechargeable battery makers and cell phone makers/retailers have intentionally steered all the cell phones towards those batteries because they know they don't last as long as perhaps nimh. If you are going to make something the quicker it wears out the more you can sell parts for it or new ones.

I hope we are both wrong about lithium rechargables, it may be something else causing them to have a shorter life than perhaps the technologies they are replacing. Perhaps overdischarging them wears them down sooner, that is discharging them below a *normal level* of some sort where a slightly higher level may allow them to last longer.
I have 3 lithium cell phone batteries but nothing set up to charge them and nothing that screams out use them for it.

Now if you could only make SLAs last even longer that would be nice. I hate replacing my car batteries every 4.5 years almost like clockwork.


----------



## MrAl (May 13, 2005)

[ QUOTE ]
*Lynx_Arc said:*
I hope we are both wrong about lithium rechargables, it may be something else causing them to have a shorter life than perhaps the technologies they are replacing. Perhaps overdischarging them wears them down sooner, that is discharging them below a *normal level* of some sort where a slightly higher level may allow them to last longer.
I have 3 lithium cell phone batteries but nothing set up to charge them and nothing that screams out use them for it.


[/ QUOTE ]

Yes i hope everyone is wrong too /ubbthreads/images/graemlins/smile.gif

The li-ion chargers are REALLY easy to make... a LM317
plus small dc wall wart does it as you probably know.
I've used mine a few times already before going to a
switching regulator type charger (just recently tested too).
I only have to put a LED indicator on it now so i dont
have to use a meter to determine when it's charged.


Take care,
Al


----------



## Lynx_Arc (May 13, 2005)

I may have a 12v charger for lithium batteries but the odd size of the battery packs makes them less desirable because if they go kaput I wont be able to replace them with like sizes on the cheap. I have been tempted to pick up some lithium AAAs and make some of my old nice AAA incans into LED lights. 
What is interesting is rechargable fluorescent lanterns only seem to be available in the 4-6watt straight tube design while SLAs are now everywhere in tons of cheap $10 spotlights. I wonder how many different sizes of SLAs are in all the spotlights or is there perhaps just a few sizes of 6v and 12v that everyone uses. It is to the point when the battery dies in these lights you throw the whole thing away and buy another one because prices on the replacement batteries looks higher than the whole thing.


----------



## MrAl (May 13, 2005)

Hi Lynx,

Oh yes, good point. I have a small two-tube fluor lantern
too, which would really benefit from having a 6v SLA
rather than four 'D' cells, which i dont like to keep around
because that's about the only thing i use them for.
I might be able to retro fit it to a SLA, but it would
probably involve lots of case changing by cutting, glueing,
etc., which would probably really ruin the appearance.

Hmmm, now you got me thinking /ubbthreads/images/graemlins/smile.gif
Maybe a small change such as installing one of those dc
power jacks and make up a 6v SLA that would plug into
it...i guess the only prob there is the SLA would have to
be carted around with the lantern, which makes it less
portable i guess. Unless, perhaps some sort of mounting
which allows the SLA to be attached right to the lantern
body when it's in use. If the SLA had multiple jacks
installed on it, that would allow several things to be
plugged into it (like you were talking about prevously)
like a drill, etc. Hmmm...

Take care,
Al


----------



## Lynx_Arc (May 13, 2005)

I thought about getting that twin 9w tube lantern at wally world and putting in a DC input jack so I could run if off either a car battery or a 12v SLA instead of having to feed it 8D cells like mad. If you ever bought alkaline D cells after about 4-5 sets you can buy another lantern for the same price as they tend to cost about $1 each unless you buy a brick of them. One SLA recharged about 6 times means you get a free lantern for the price of just the batteries.

It isn't overly hard to put in a DC in jack if you can find the type that takes two small screws you just have to find a place to put it and drill 3 holes, 1 for the plug and two for the two screws to attach it to. The alternative is taking the bottom off and using clip leads if possible. I have two GE 4watt fluorscent touch lights connected to two battery packs with clip leads. I also wired in a DC input jack to a battery powered fan and an 8AA blacklight. 

I pick up super cheap fluorescent lights so I can later rip the guts out of them to make into other lights. I am also looking for super cheap battery lanterns to mod into LED/Fluorescent. SLAs and fluorescent lighting are great match and few companies have made lights worthy of the two together.


----------



## MrAl (May 14, 2005)

Hi again Lynx,

Oh i didnt know they were actually being made already.

I like the idea of running off of the 12v SLA too, but
i would have to contruct a switching regulator for that
to step down from 12v to 6v (not really a problem) as 
i wouldnt want to waste all the battery energy (50% eff).

Yeah, maybe the clip leads would do it, but im thinking a 
little more permanant so i'll probably go with the jack
or plug to connect to either a 6v SLA or 12v with regulator.
In any case, at least i'll get some use out of my nice
lantern for a change /ubbthreads/images/graemlins/smile.gif

Where are you getting the cheap fluor lights?


Take care,
Al


----------



## CNC Dan (May 14, 2005)

[ QUOTE ]
*MrAl said:*
Hi Lynx,

Oh yes, good point. I have a small two-tube fluor lantern
too, which would really benefit from having a 6v SLA
rather than four 'D' cells, which i dont like to keep around
because that's about the only thing i use them for.
I might be able to retro fit it to a SLA, but it would
probably involve lots of case changing by cutting, glueing,
etc., which would probably really ruin the appearance.
Al 

[/ QUOTE ]

In the future, try to buy lanterns that use the big square lantern battery. You can get those types of batteries in SLA. No mods needed and you have a rechargeable SLA lantern. You can also find adaptors that will take 4 D alk's and go into a lantern.

Dan


----------



## Lynx_Arc (May 14, 2005)

MrAl
It is easy to use a 12v SLA to power fluorescent lights either use 2 6v setups (ballast/tube) or one 12v setup. I have a closeout place here I once picked up some GE touchlights for $1 each (both were selling at walmart in excess of $7. I picked another one up for $2.50 and have seen more at BigLots for about $3-4 each. I picked up 5 Coleman micro fluorescent CCFL 6v lanterns that run off 4AA cells for $4 each awhile back for *projects* and also have a pull chain fluorescent light with a 6v 6watt setup that takes 4D cells I converted to AC operation with a DC input jack and walwart. After looking at various ballast/bulb combinations I have come to the conclusing that for lanterns the limit in straight tubes is 6watts, anything bigger starts to get too long. That is why they are using Utubes and twister bulbs and it is quite tempting to construct a ballast circuit and take apart a 100 watt equivelent or even a 150watt 3way fluorescent bulb for an SLA based lantern.
You could use a 12v 15Ahr SLA and at about a 3A load on high by my rough estimate you would get 5 hours or portable *almost daylight*. 

CNC Dan-
There are very few lanterns new in the stores using the 6v lantern batteries now. They are hard to find as I have only seen one and it wasn't cheap at $12 with an incan bulb in it. I have a SLA spring top lantern *replacement* battery and a 4D-lantern adapter both awaiting a lantern to put them in at this time. Seems manufacturers would rather you put them in a flashlight than a lantern now and I don't blame them as the cost effectiveness of such batteries isn't good compared to 4D cells. I even saw a pack of flashlights with a 6v flashlight that came with an adapter in it stuffed with 4D cells at a grocery store the other day. For flashlights I prefer not to use lantern batteries as the excess weight doesn't justify the rather dim non halogen bulb they put in them. From there you go to SLA spotlights. 

Now I almost wished I had bought a few more of the SLA spring top 6v batteries for $4 on clearance at walmart.


----------



## MrAl (May 15, 2005)

Hello again,

Dan:
Oh i didnt know they made 6v SLA's in the same case size as those
standard 6v lantern batteries. I'll have to look around i guess.
I dont know of any lanterns that take that kind of batt and have
fluor tubes though. Most of the lanterns i see that take that
batt have a incand bulb with reflector. They are only about 4 or
5 bucks, but that's not the kind i use.

Lynx:
Well, my current fluor lantern takes 6v, not 12v, so i'd have to 
either use a 6v batt or step down my 12v batt.
I havent been to wally mart for a while now, but next time i visit
i'll check out their lights again. I check from time to time, but
havent for quite some time now.
Are you talking about using a step up circuit to drive one of those
twister fluor bulbs made for 120vac? Not a bad idea i guess. I have
two that consume 15 watts but put out the incand equivalent of about 30
i think. Would be interesting for sure...have to give this some thought.
BTW, how many amp hours are the 6v SLA's in the case of the usual 
6v lantern battery?


Take care,
Al


----------



## Lynx_Arc (May 15, 2005)

MrAl
With both 6 and 12v SLAs available it is more practical to get the right voltage. I think it would be better to just design or use a predesigned ballast circuit for a twister bulb. I was thinking along the lines of yanking or dissasembling a 75 watt or higher twister bulb and attaching it to a 12v ballast circuit. Your 15watt twisters are equivalent 60 watt incan. My 6v SLA spring top is 5 Ahr I am not sure how an alkaline or heavy duty compares Ahr.
5Ahr isn't outrageous compared to near 4Ahr nimh subC but then again the advantages of not having to top them off as often is the advantage for sure.


----------



## MrAl (May 15, 2005)

Hi again Lynx,

Yes, i meant to say 60 watt, not 30 

Do you know where to purchase the 6v SLA's with the 
spring top terminals now?

Take care,
Al


----------



## Lynx_Arc (May 16, 2005)

MrAl 
I believe batterystation has one but it is about $12.50 I think. I found one here http://www.zbattery.com/ub650.html
for under $10 that looks like mine.
here is another place http://www.batterymart.com/battery.mv?p=SLA-6V5-SPRING
for under $9 plus sells a charger for it also.
I am sure if you look around you could track one down cheaper online or even find one local at perhaps a place that sells batteries for alarms and commercial applications.

I was lucky to pick mine up on clearance at walmart for $4
they were $10 for about 6 months but I guess nobody was buying them so they stop selling them. You could just find an SLA of the same size with any terminals on them and adapt it to your use by either adding springs or soldering some connectors to it.


----------



## MrAl (May 16, 2005)

Hi,

Oh great, ill check them out.

This is actually for a friends 'lantern' (mine can use the
normal 6v SLA i think once it's fitted) where it's one of
those incand type that comes with the battery and i've
retro fitted it with a Luxeon. The lantern normally holds
a 6v'er just right (pretty much) but wont hold one of those
smaller 'normal' 6v SLA's without some padding or something,
and i havent even checked the height to see if it would
even fit inside...ever try that?

With my fluor lantern i can use those smaller 6v 4Ahr 
type SLA's and i like those better anyway because
they seem smaller.

The 'spring' type 6v'ers you've pointed out will fit really
nice into my friends light, so all that's left is a 
charger which im planning to build out of a wall wart
and maybe a LM317 regulator.

I think we all like those 6v spring lantern batteries,
but we dont like to keep buying them /ubbthreads/images/graemlins/smile.gif so the SLA will
be a really nice change.

Take care,
Al


----------



## Lynx_Arc (May 16, 2005)

I liked the massive runtime on 6v alkaline lantern batteries but IMO a .75A krypton 2D flashlight is just as good and batteries are cheaper. I have 2 or 3 6v lanterns one with an alkaline battery in it, one that has a broken wire but I wont bother to fix it becaue I don't plan on using it I bought a cheap dorcy 6v incan lantern for $1 I thought about modding for LEDs and fluorescent but it is to small for fluor use (not enough room for the tube. 
I saw one place that had a 6Ahr spring top SLA but they wanted something like $16.95 so I shook my head and closed that page. 
I have a long 12v SLA I got for cheap but it is not a size that would be easily put into a light. It is kind of about the size of a carton of cigarrettes I think? (I am guessing since I dont smoke).
It would be nice to have 3 Ahr SLAs the size of 4 D cells, essentially just a shorter version of the lantern battery
but I don't think there is any. 
If I could find a small SLA about the size of 4C cells I could use it in my next mini lantern project but I am guessing the capacity would be dissappointing and runtime would be inadequate.
I have never messed with LM317 but as a kid I used LM309s to make 6-9v regulated output from a 12v source. I still have the board that I hooked to 3 computer SLA batteries with them mounted on.


----------



## MrAl (May 17, 2005)

Hi again,

They are getting $14 for the 6v 4Ahr SLA's at Home Depot
so i havent gotten one from them yet...i dont think they
are worth that much really.

The LM317 is such a versatile regulator i've been able
to construct several devices:
1. Adjustable power supply
2. 1 amp Li-ion charger (could go higher than 1amp too)
3. Lead acid charger on the way at some point
4. LED driver

and all of the above usually only require a few resistors
in addition to the LM317 itself. The power supply even
doubles as a 1 amp Li-ion charger when you set the
output to 4.200 volts.
If you take a little time to look at that chip you
wont regret the time spent.
Oh yeah, cost for the chip is maybe 50 cents on some
parts web sites.

Take care,
Al


----------



## eluminator (May 17, 2005)

From BatteryMart I got a 6v-4ah for $4.95 + $6.89 S/H
From RageBattery I got a 6v-4.5ah for $6.50 + $9.11 S/H OUCH.


The voltage regulators are neat chips. I don't know beans about Li-ion batteries though. I've got one good camcorder battery and two more that are dead as a door nail.


----------



## Lynx_Arc (May 17, 2005)

I agree $14 is a bit too stiff for an SLA unless you are using the device often, but taking the price of alkaline lantern batteries it would take only 3 of them to pay for it. I think 6V SLA would be a good deal at $10 or under including taxes/shipping I will keep my eye out for them at such prices.
Batterystation has some odd sized SLAs for $5-6 which may fit but shipping would probably cost more than the battery.
My spotlight from harbor freight has an SLA in it and it is on sale for $7.99 but I don't think it will fit a lantern it looks taller and rectangular, I will measure it later if you are interested.
I will have to check into the LM317, They do sell it in the quarter sized package (cannot remember the To designation).
It would be nice to be able to also put charging chips in a lantern so you just plug it into a walwart instead of having to clip on leads or take batteries out.

eluminator- I know just as much about li-ion batteries as you do. I have 4 cell phone batteries I got for $2 I haven't messed with yet, one is 7.2v 1400mah the other two are 3.6v 700-800mah cell phone packs. I tried to sell them all for $1 each and nobody wants them.


----------



## MrAl (May 18, 2005)

Hi Lynx,

You dont have to measure it actually, just see if it fits
into a 'standard' incand spotlight. If it does, i'll be
able to fit it into my friends light (with the led).

Yeah that would be nice to have the charging chip right
inside the light, and it's of course very possible in
the spotlights/lanterns because there's usually a little
extra space in the head. It would have to get air when
charging if using the LM317 and a high rate of charge,
but not for trickle.
Yes, a dc power jack on the side of the lantern would be
nice /ubbthreads/images/graemlins/smile.gif for charging...plug it in and wait a little.

I do that with my small LED light, except i dont have a
jack on it ... just two hooks where you can easily attach
clipleads. Maybe in the future i'll attach a small
dc power jack if i can find one small enough....only has
to handle 300ma charge current for that light.

Oh wait, i dont actually have the charger chip inside too,
but it's almost the same as the wall wart plugs into
the charger board and the charger board could then 
plug into the light where i now use clip leads.

Take care,
Al


----------



## Lynx_Arc (May 18, 2005)

MrAl I was thinking some of the odd sizes of SLAs you may possibly be able to wedge a higher output (more Ahr) into the light. I have seen some that vary be as little as .2 inches and if I can squeeze a slightly larger battery in and get another .5-1Ahr in the meantime I would. 

For smaller lights you are probably right not worrying about having the voltage regulator on board. I guess you could just create a charger with a lot of settings each one seperate for fast/slow charge, float charging would be nice also because you could just have a flashlight locker with lights stored fully charged. You only need a few lights strategically placed around the house while lanterns can be stored elsewhere within walking distance during a power outage or accessable for that camping trip.


----------



## MrAl (May 18, 2005)

Hello again,

Sorry i forgot to reply to eluminators post last time...

eluminator:
That's not a bad price really, and i think it's worth
getting one. Like Lynx was saying, it would pay for
itself pretty fast. Another thing i like about them
is that you dont have to worry as much about using
the light, as you can always recharge. This automatically
makes the light more 'handy'.

Lynx:
Yes that's a good point. I dont have the exact size
of the target light right now though, maybe i should
get ahold of it and take a few inside measurements.
That way i'd know for sure what fits and what doesnt.
Right now im really just guessing.
Right now my new li-ion charger has two settings but
more are easy because you just change a resistor.


BTW, there's nothing too complicated about Li-ion cells
really...you just have to know how to charge them
correctly if you're going to design your own charger,
or you could just build one of the ones that has been
posted here to CPF at one time or another if you're
interested in doing that.


Take care,
Al


----------



## Lynx_Arc (May 18, 2005)

MrAl
The minute I figure out a use for the li-ion cells I have or buy some to use in stuff I have ideas for modding I will definately look into building a charger or two. 

The other day I left my lights on in my truck for about 90 mins at church and the battery went dead, so I went to walmart and had them check it and the guy hooked up this electronic gadget with what looked like charging clips and approx 10-12 gauge wire on them dialed in 770 CCA and about 30 seconds later told me the battery was putting out 763 CCA. I just shook my head and took the battery and left.
When I bought the battery I had left the lights on once before in the car I had it in for 3 hours and started a V8 with it but 4.5 years later it discharged more in half the time and couldn't even budge a 4 cyl. I think the capacity of the battery is down some although the CCA may be fine I don't trust it to last. 

I don't think you can do a decent CCA test using 10 gauge wire, it would get hot and melt at 700 amps I figure so I bet they put a shunt simulating about 50amp load or less and measured the voltage drop and extrapolated the total capacity from that figure (perhaps multiplying by 14 or something.

I have been eyeing the 3v AAA li-ion as I have a few pelican mitylights that kept frying bulbs I may mod for LED use.
With an integrated charger I could also make a lightweight headlamp using a 800mah lithium pack I have.

I saw a lantern at biglots for $10 that comes with a 4D-6v adapter but it is a flashlight, I feel lanterns are for area lighting but for some reason anything using large 6-12v batteries is sometimes called a lantern.


----------



## MrAl (May 19, 2005)

Hi again,

I think you're right about the extrapolation technique. I find it
hard to believe they applied a load of 700 amps to test it, especially
with somewhat small clips on thin wire.
Usually the problems with car batteries appear after they've been
run down once, but i've never had your exact situation occur...mine
always ran down once they got too old (past the warrenty) and it was
very cold outside.
My last battery was weak (you could tell by the way the car turned over
in very cold weather, very slow and in slow spurts) and i knew it was
getting old so i bought a new one before i had a no start condition.
I went to walmart too and ended up with a slightly bigger battery, 
which i liked.
Oh yes, the 3.6v li-ions make very nice batteries for LED lights,
even with just a single series resistor. My smaller LED light works
like this (AA size) and i get plenty of run time and get very little
self discharge. The LED starts to dim once the cell runs low so you
dont over discharge (series resistored version). This is one of the
reasons i like them so much. Yes, the cells arent too heavy either
(especially only one to run the whole light) so it would make a good
headlamp.
I used my fluor lantern for reading one time when the power went down
and it worked pretty good. Yeah, it's sort of an area light but it
did work for reading too.

BTW interesting verse you changed to 


Take care,
Al


----------



## Lynx_Arc (May 19, 2005)

I find car batteries last between 4 to 5.5 years for me so around 4 years if they start acting up I check them out and see if I can replace them. I always get the largest battery that will fit the tray as prices on them are usually the same for all sizes of a line and regardless of engine size and need a larger batttery gives you more headroom in emergencies including helping jump start other vehicles.

I have 2 3.6 lithium flat cell phone batteries and what looks like an oversize two AA side by side 7.2v 1400mah pack. I wonder if this pack has two cells in it at 3.6v
plus some sort of protection circuit in it. 

I have used all sorts of lights to read at night from fluorescent to incan to LED. I have been *thinking* about a fluorescent headlamp design for awhile but haven't found a host or small enough CCFL and large enough housing for it without being clunky looking and top heavy. I mostly use LED headlamps now to read by in bed now and prefer the single strap 3AAA headlamps due to the lighter weight and less pressure comfort. 

Glad you liked the verse, I had the prior verse in honor to my mother who passed away in 2001. I like to change things now and then, even my desktop wallpaper changes every 6 hours automatically. Guess I am glad I am not a woman so I don't have to change hairstyles often. /ubbthreads/images/graemlins/drool.gif


----------



## MrAl (May 19, 2005)

Hi there again Lynx,

Oh yes that's about how long my car batteries last too come to think
of it. The space for my car battery is so small i was lucky the
slightly bigger battery fit this last time. The wire was serviced
too and the guy made it too short so that BARELY fit on the bigger
(taller) battery. Almost had to bring it back.

That Li pack sounds like a two cell 3.6 x 2 pack that i've read about.
Yeah, the manufacturers usually put in a protection circuit because
of all the problems that can come about if shorted. I dont use
protection circuits in mine but a simple fuse would suffice im sure.

My headlamp is 4xAA and it's not too bad i guess using NiMH cells.
It's the only one i have so i have to use it, but it's not that 
heavy i guess. Really comes in handy for some things like servicing
something where you would normally need a flashlight.

Very sorry to hear about your Mom...i know what a life changing event
that can be as i lost mine back in 1996. Life is very strange 
sometimes. If it's any consolation i've heard that for a parent, losing
a child is an even worse experience.


Take care,
Al


----------



## Lynx_Arc (May 19, 2005)

I thought about dissasembling the pack for the individual cells but I don't have a light I would put them in if they were bigger than AA size. I have 2AA,4AA,3AAA,4D,and an SLA headlamp so far. I find the 4AA headlamp the least comfortable because the cell pack in back.

It is no fun to lose anyone you love, but at least I got to know her which is better than some people who lose a parent when they are a child. I cannot imagine losing a child but seeing my grandmother when mom died was terrible it may all but kill her also. 

I would recommend getting a 3AAA led headlamp to use, you will find you use it more often due to the comfort. Get one that has the single band and doesn't have the slide in cartridge but 3 cells on the same plane as they fit closer to the head and are lighter. I find I like the feel of my eveready hardbeam etc pivoting 2/1 LED light a lot even though the *ball* shaped optic beam takes a little getting used to. I have 2 cheap target no named 3AAA 3LED inline headlamps and like them too for two reasons: they cost me $2.50 each, and the whold light come loose from the headband and has a magnet on them you can either set down flat or on a metal surfact.

I am tempted next time harbor freight has their battery testers on sale (the ones with a huge nichrome wire resistor and 4 gauge leads) I may get one because you will always have car batteries to test. I have been reading about people that use computer backup inverters hooked to large deep cycle marine or car batteries to power stuff off of and may look around for dead UPS with a large inverter to try that also. I saw a 1200watt inverer for $80 and was thinking....

Russell


----------



## MrAl (May 20, 2005)

Hello there Russell,


Oh yes, i've heard about some people taking apart the packs to use the individual
cells so it must work out pretty good. The new cells arent that expensive either
i guess and they are rated higher. The initial cost is a little higher yeah, but
it seems worth it. The way i figure it by the next time i need to buy cells
(barring the creation of a totally new light hee hee) they will have even better
cells out on the market.

A 3xAAA headlamp does sound interesting, but i am more of a sort of runtime
junkie...i like very longggg runtimes /ubbthreads/images/graemlins/smile.gif Would be nice to have a more comfortable
fit however.

The car battery tester sounds interesting too...how much do they run (in USD)?
I'd like to test my battery with one too from time to time, especially just before
the cold weather is about to hit.
From time to time i've been thinking about going the inverter route too...that way
you can power anything from the car when you need to do something outside or
on the car or whatever. 1200 watts wow, that should power just about anything, maybe
even a microwave oven. Let me know if you try that ok?
I was even thinking perhaps a smaller unit for things like my big soldering gun,
computer, etc.


Take care,
Al


----------



## Lynx_Arc (May 20, 2005)

My 3AAA headlamps seem to last several hours off nimh cells I yanked from old cell phone packs... 550-650mah batteries. I like them for using around the house and tiny size. You can put them in a pocket easily. Most of the time I don't need more than about 2 hours of runtime on a headlamp but I have the SLA one and one that uses AA,D, also. The longer runtime is nice but comfort and ease of putting on/taking off makes you desire to use a headlamp more often. Before I got my first incan headlamps (hosts for projects,2AA clone)
I didn't know how nice they would be, but found out the incan cheapos ~$4-7 rayovac *clone* incans really don't inspire you to use them compared to a nice LED flashlight, the beam is terrible. When I came across my cheapo 3LED headlamps after I got used to them I find myself picking one up instead of a flashlight due to the hands free capability. I have a fairly bright 12x26kmcd headlamp made from modding a 2AA incan that blows away all my other LED lights (no luxeons yet) and the weight, bulkiness and strap over the top discourages me from using it where I can get by with a single strap AAA low profile headlamp. My advice is one long bright runtime headlamp and a 3AAA low profile one for quick usage. If you get a headlamp that sits fairly flat you can also point it at the ceiling as an area light. I prefer the switch on my cheapos better than the energizer headbeam because it is just a digital push button instead of a slide switch. 

I haven't looked at prices of car battery testers but I am guessing in the 40-80 dollar range that is why I haven't really got one yet, for that price you can just about buy a battery and forget testing.

I have been occasionally eyeballing inverter prices somewhat and have seen prices falling continually. 1200 watts is about 10amps and probably drains close to 15 or so from a battery. The inverter claims a peak of 2500 watts which is needed to start motorized equipment such as fans and computers with drives/fans etc. Unless I find an outright steal of a deal I figure inverter prices will continue to keep falling as the chinese slowly saturate the market and competition gets fierce. My guess is 250 watt inverters may be going for $9.99 at walmart in a few years perhaps and 1200 watt ones for $25 within 5 years. I could be wrong though. Inverters vary also... output may not be nice enough AC to drive some equipment I have heard.


----------



## Lynx_Arc (May 21, 2005)

I just stopped by Academy sports and spotted an SLA that was the same size as a lantern battery 6v 5Ahr but it had tabs on it. It was about $10 and was the only one of its kind sitting next to a bunch of 12v SLA 7Ahr batteries priced about $15 each. I was unimpressed by their selection of lights and pricing including a 38.00 8led tree sitting light I have seen elsewhere for $10-12.00. I also chuckled at a *new* idea of rechargable kids lantern by coleman. It looked like a small lantern with screenwire and a pivoting lid on the top.... you are supposed to catch fireflies and use them for lighting. Don't tell the micromodders of this they may try to mod a firefly with an LED. /ubbthreads/images/graemlins/crackup.gif


----------



## MrAl (May 22, 2005)

Hi again Lynx,

Oh yeah, 40 to 80 bucks is certainly a new battery geeze.
Im not sure i'd want to pay that much, but then there is
perhaps the possibility of making one...connect a meter
to the battery terminals and load the battery and count
the seconds and take a reading (new battery). A year
later repeat the same procedure and take the new reading,
two years later, etc. At some point the reading will
be much lower indicating the battery is going.
Would have to be a nice heavy load though, like maybe
100 amps.
With my last old battery i saw the meter fluctuate more
than previously (up and down) as the car was being 
started (starter stalling, then starting, then stalling etc)
which told me the battery was going. The dips are lower
too. With a new battery that doesnt happen even in the
colder weather (at least not as badly).

That SLA sounds very interesting, but that kid's light
sounds very funny... and perhaps might draw the attention
of the animal protection agency: exploiting the mating
habits of an animal, ha ha.

Take care,
Al


----------



## Lynx_Arc (May 22, 2005)

MrAl
SPCFF would boycott my house if I got one. I remember catching fireflies (we called them lightning bugs) as a kid into a jar but trying to read by that light is a mess unless you got about 20 of them forget it. 

I recently picked up a lithium ion camcorder charger for near nothing and am trying to figure out if it would be usable for charging all lithium cells as the case says 3.6v and 7.2v and it has a small microproceossor in it and about 30 other components, even and inductor and also a large torroid coil. I started a thread to see if anyone else knew much about it. I am wondering if there is a DC/DC buck circuit as it takes [email protected] walwart on it. I looked up about half of the 30 or so camcorder batteries it is supposed to charge and they are rated from 1000mah to 5550mah mostly 7.2v and it has a bunch of contact pads I am trying to figure out. The model is Ambico v0916. Is it possible to make a smart li-ion charger that can detect both voltages of batteries and charge different ratings without damage? Someone said camcorder batteries had protection circuits preventing overcharge. If this thing was smart enough then perhaps other smart camcorder chargers could be used for charging batteries commonly sold/used on cpf and in lights.

I still haven't been able to get in touch with the guy I got my headlamps from (sla setup), but I will try again next weekend perhaps I can come across him. I stopped by home depot and they had some skinny 6v SLAs for powering emergency exit lights that were too expensive. I noticed the larger ones had some sort of date stamp that said charge by XXXX date which was something like november last year. I wonder what the deal with that is? 

Next thing you know some silly CPFer will get a large straw and put a FF in it and try to sell it for $5, then try to sell replacement insects when the *charge* dies down.


----------



## MrAl (May 22, 2005)

Hello again Lynx,

It's possible that that circuit detects open circuit voltage
and adjusts it's output accordingly, but i dont have the
circuit in front of me so im guessing based on what you've
said so far.

Yeah those skinny 6v SLA's are the ones i was looking at 
I wasnt sure if they were too tall for your average
cheap incand spotlight. And yeah, they are expensive 
for what you get i think. 
If the date is past the 'charge by' date i'd wonder if 
they werent too old now.

Fireflys...hee hee...the worlds next natural energy source
ha ha.


Take care,
Al


----------



## Lynx_Arc (May 22, 2005)

MrAl,
I believe it may do a voltage test and adjust accordingly.
I guess I will have to hook an ammeter and voltmeter up to my 7.2v pack and try it out carefully not to blow up the world.

Lets just hope they don't clone fireflies and made flashlights out of them, then you will have to feed your latest light nectar or whatever they eat to keep it going.


----------



## MrAl (May 23, 2005)

Hi again Lynx,

Yes you'll have to be a bit careful, although a small 
resistor in series might help for the initial tests to
limit current.

I was thinking...install an electric motor in my car,
then a big solar panel, using the light from a whole
bunch of fireflys to power the solar panel which will
then drive the motor...The first firefly driven car
ever /ubbthreads/images/graemlins/smile.gif


----------



## Lynx_Arc (May 23, 2005)

MrAl,

Feeding the fireflies may be more trouble
than it is worth, you may have the stench of
1000 dead fireflies on your car in the hot summer.

I charged all three li-ion batteries last night.
One was 800mah and started out charging at 750ma then dropped off gradually. There is a dc/dc converter working as I was only using a 400ma 12v DC brick and was getting 750ma at 4v out. Apparently the charger is smart and I am guessing is pulse charging because the current wobbles up and down every fraction of a second. I don't know what the max charging rate of Li-ion is but I figure 1C is probably ok for a short time as the battery didn't heat up. If needed I have a 100ma 12v brick I could use to more limit current.


----------



## MrAl (May 23, 2005)

Hi Lynx,

Hee hee...

Sounds like you had some very good luck charging your Li-ion's
and the charging cycle sounds normal...mine charge up at
the rated current (300ma or about 1000ma depending on 
setting for the particular cell) for some time period
(maybe an hour) and then the current starts to drop off.

Yes, if you're putting in 400ma and getting almost twice
that out it must be a switcher, UNLESS the 12v brick is
actually putting out more current with less than 12v out,
which is typical of wallwarts too. An input current 
measurement would tell you for sure. For example...
with 9vdc input my switching charger draws a certain 
current with 1 amp output, but with 15vdc input the
input current is almost half that, because there is 
genuine power conversion taking place. I was even
able to run it on a 12v 200ma wall wart! because the
voltage of the wall wart dropped down to provide
a little more current output. I was going to test it
on a 24vdc supply but never got around to it (yet).

It's pretty amazing when you see the difference between
using a switcher and a regular ol' linear regulator as
to input power requirements.


Take care,
Al


----------



## Lynx_Arc (May 23, 2005)

MrAl, 
Now I just have to remove all the contact plates and attach some clip leads to it and reassemble it. It would be nice If I could get a cheap tiny DMM ciruit with LCD panel and incorporate an ammeter into the charger. I figure it has an actual DC/DC converter as I see little reason for the torroid coil about the size of a nickel with lots of what looks like around 18 guage wire on it and an inductor bigger than a pencil eraser by about 50%. 
I would have bought two of these if they had them there for 70 cents each. I did pick up a 15v 1amp walwart and 12v 900ma walwart for 1.25 each. I collect walwarts if I can get high output ones for around a dollar because that 15v one costs about $15-20 at stores or more and you can always rip them apart and make a better regulated supply using the transformer if needed. I almost bet that charger would work off a 9v walwart but just wouldn't charge as high a current.

I think you are right about a switcher, It has a microproccessor and the current changes like clockwork constantly which non switchers don't do, they just change randomly now and then and not nearly as often. Now I just have to get some more ammo to charge.

Oh they had 10v SLA camcorder batteries 1600mah for... get this 50 cents each AND 75% off of that so I could buy them for about 12 cents apiece... I didn't buy any though because I don't have a charger nor a use for the size of battery.


----------



## MrAl (May 24, 2005)

Hi Lynx,

You must be right then about it being a switcher too...
i cant see why they would want to use inductors otherwise,
but it doesnt take long to measure input and output current 
either.

70 cents each? wow, where the heck do you shop? /ubbthreads/images/graemlins/smile.gif

50 cents each too? wow, where the heck do you shop? /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/smile.gif


Take care,
Al


----------



## Lynx_Arc (May 24, 2005)

MrAl,

I shop at closeout stores. They buy inventory of store stock either discontinued or the store closes. It just happened I was looking for something at one closeout store for somebody on CPF and stopped by another closeout store that was.... closing out (lost their lease) so there was a 75% off everything in the closeout store, so cheap upon cheap. 

every once in awhile I pick up name brand batteries for dollar store generic prices at the places. I got an eveready 123 battery for $1 at one, I don't know what I am going to do with it but I will figure something out in the next 10 years. I have a BigLots next to the grocery store I shop at to buy some things so I am in there about once a week and find bargains once every few months. We have several local only closeout stores but shopping them is tricky because many of them are using the closeout formulae to get into the dollar store business and as their supply of items deplete and they cannot find other stuff to replace it they start buying dollar store items and selling them alongside. BigLots is like that, half dollar store, half closeout store. You can have one bargain next to stuff priced higher than walmart sells them. 

I believe Walmart was founded on the same idea, Sam walton bought out closeout stock from other stores/sources and resold them and the later started adding regular stuff then dropped the closeout stuff completely.

If I can come across my source I got my SLA headlamp from perhaps I can get a few bargains this coming weekend to share.


----------



## MrAl (May 25, 2005)

Hello again,

Very interesting about the closeout stores and Walmart too.

Around here we only have dollar stores, and some of them
insist on selling some items for more than a dollar (like
1.50) and they dont mark them or tell you until checkout
time...really stupid. One time almost everything i picked
up was 1.50 and it just struck me as deception so i left the
junk and left the store without purchasing anything /ubbthreads/images/graemlins/smile.gif
Next time i went back most shelves were marked!


Take care,
Al


----------



## Lynx_Arc (May 25, 2005)

MrAl,

I was just at walmart last night and saw something interesting, a cordless phone base power outage supply. You plug your cordless phone base power adapter into it and it into the base and when power goes out the SLA in the unit takes over. They had it on clearance for 17.00 but perhaps they will mark it down and it won't sell. Looks like it may have a 4ahr SLA perhaps. 

There are a dozen different types of dollar stores, I avoid them most of the time because most are anti-bargain. They would take a 74 cent item sold in walmart and sell it for a dollar or take an item than sells for 1.99 at 16oz and sell a 5-6 oz version for $1. About the only bargains are closeouts and most dollar stores have very few of them.
I got to use my 12v 2ahr SLA to test my roommates car fans, not a high output battery but for $3 it is a small 12v test device easily portable. It is interesting you can get a 12v 7Ahr sla for $15 and it costs about the same for 8 2500 nimh AAs and even more for larger sizes. In another thread they are running a coleman 15watt fluorescent lantern off an SLA and finding it can put out more wattage with it possibly making it run hotter. One of my closeout stores had eveready alkaline 9v for 1.50 and 1.88, seems they cannot figure out how to mark things the same and don't have price scanners.
I hate trying to find price scanners in walmart either they are broken or a mile away from where you are.



Russell


----------



## MrAl (May 25, 2005)

Hi again Russell,

The dollar store around here vary with what they sell and
the actual 'bargain' varies too /ubbthreads/images/graemlins/smile.gif Sometimes is, sometimes
isnt. Have to be careful what you buy because of the 
possible very low quality might render it virtually useless.
Some things are hard to go wrong on...for example i got
a small hammer with screwdrivers inside the handle...i
didnt need the screwdrivers but the hammer was just the
right size for punching marks on a pc board with a small
center punch for later drilling.
Oh 12v 2Ahr, i had one something like that but i didnt use
it for like 2 or 3 years and it went bye bye /ubbthreads/images/graemlins/smile.gif I didnt
get around to checking it every now and then so that's that.
Makes a good paper weight now /ubbthreads/images/graemlins/smile.gif

I'd like to find that other thread too as my coleman is
about 15 watts too i think (dual bulbs).

I also find a lot of the stores to be a pain with no prices 
on too many items. Many people give up and never buy
the item because they dont feel like finding the price.
Lately i take the item with me up to the register and
ask before they ring it up and decline if it's not priced
the way i think it should be. Let them put it back then /ubbthreads/images/graemlins/smile.gif
If the item's too big you cant do that though...like a 
big storage cabinet one time.


Take care,
Al


----------



## Lynx_Arc (May 25, 2005)

The thread is about the 15watt *twister* collapsable lantern coleman just came out with. It appears to have a tube similar to the 60 watt twister (which is rated at 15watts power usage)
in it. I find 8D cell lanterns give you a lot of light/runtime but replacing 8 alkaline D cells when it runs out 5 times a year gets the *UGH* factor going. 
If I had an 8D lantern I would try to at least adapt a subC nicad pack to power it if I couldn't fit a decent SLA in it.
I have had stuff powered by D cells and anything above 4 gets me thinking about SLA external power (or internal even). I have a bookshelf sony stereo that you can swap out the power section for a battery holder that holds 12D cells and has a 12v input also. I only used it once off of batteries and a few times off a car cigarette lighter socket. With small 12v SLAs priced at about $15 I have been thinking about SLA motorcycle batteries. If you could find one around $20 that would probably be the breaking point as beyond that price unless you needed the smaller weight/size you can start buying cheap car batteries instead. 
I figure it is almost cheaper to buy a cheap spotlight to get an SLA than to buy an SLA, the trick is finding out which lights have which batteries in them.


----------



## MrAl (May 26, 2005)

Hi again Russell,

Oh ok thanks, ill have to find that thread as it does
sound interesting.

Yeah i wouldnt even purchase a lantern with 8 D cells /ubbthreads/images/graemlins/smile.gif
I didnt even purchase the one i have (4 x D cells) as it
was a gift way back when.

Oh i didnt know they use SLA for motorcycles now, i thought
it was the standard car-type LA only smaller.

There's a HUGE light being sold at a local Costcos
for $25 and i think it has an SLA. It's the biggest
spotlight i've ever seen...must be 18 inches long.

BTW, cant find the thread on the twister bulbs...


Take care,
Al


----------



## Lynx_Arc (May 26, 2005)

Mr Al,
I don't know if they use SLAs on motorcycles but I figure that they have some batteries similar in them or in the small offroad vehicles. If you don't mind a regular lead acid battery for cheaper it would do in a pinch. My cutoff point on SLAs is about $20 because regular lead acid batteries come in at that point with a lot of capacity and at the weight they are at they are not going to be put in any device but be external in perhaps a box or have a handle on them.

The thread must have gone cold it was about the coleman collapsable lantern I am sure it will pop up and I can post you the thread link here when I see it again.

I think it would be fun getting an inexpensive LA battery and wiring in some LED emergency lighting in a house. A $25 battery and 100 cheap 5mm LEDs and a spool or two of wire, some switches and perhaps a circuit to detect power loss and another to charge/float the battery and you are done.


----------



## MrAl (May 27, 2005)

Hi Russell,

Oh yes, that would make a great emergency light.
Wouldnt be hard to make either. Even a couple of LED's
would work too as that would give enough light to find
larger light sources like your lantern if the lights went
out.

Ok i guess i'll have to wait then to read about that
special lantern powering project 


Take care,
Al


----------



## Lynx_Arc (May 27, 2005)

I think I saw a spotlight at Harbor freight that has a 12v 7Ahr SLA in it for $15? That would almost make the light free compared to the battery price paid. I am looking around for cheap 12V SLAs right now just for fun, if I come across one at an irresistable price I will probably bite as my little 2.3Ahr is woefully small for any sort of long term use other than a handful of 5mm LEDs or 4watt fluorescent tubes for about 8 hours. They also had the 12v float charger back on sale for $6.99 at HF (harbor freight) I also saw a 10amp,50amp, and 100amp battery testers there and was intrigued until I saw the prices. I think it is interesting I have been looking at 12v sla chargers and don't see any that charge less than 2amp rate. I have an old 6/12 volt charger with a 6amp scale that also allows .2amp-1.2amp charging I will probably use to charge my 6v lantern SLA I have. I have seen lead acid chargers listed as smart but I wonder if any of them can be dialed in at a rate and when completed trickle charge to finish then go to float. I feel constant trickle charging over time ruins a lot of lead acid cells out there prematurely due to overcharing while an intelligent charger with float ability could extend life of batteries.


----------



## MrAl (May 27, 2005)

Hi Russell,

That price sounds pretty good for the 7Ahr battery.

Also, did you happen to notice the sale on the 100 amp
(small) battery tester? $14.00, and im temped to get one..
shipping is $7 that brings it up to 21 dollars for 100 amp
tester.

Also, from what i've read about that tester the load is
applied and the voltage is measured and the meter is
scaled to read off CC Amps, which is what you guessed /ubbthreads/images/graemlins/smile.gif
But, i got to thinking...(even though it's late in the day
for me he he) what if one were to purchase an inverter,
say 1000 watt model, and hook it up to about 1000 watt
load and connect it to the battery. The current draw would
be around 100 amps (or so) and one could use a digital
meter to take the reading.
The correlated scale looked like this:

11.2 volts (1000 CCA's)
down to
10.0 volts (200 CCA's)

That's basically 0.0015 volt per 1 CC amp, which means
we could calculate the CCA's:

CCA=(V-9.7)/0.0015

with 100 amp load!

The load would have to be selected to make sure we got
100 amps out of the battery for the test (for 5 seconds).
Im not sure how we could do this however, without a 
100 or 200 amp current shunt.
On the other hand, comparatively we could measure the new
battery and note the reading and compare it to later 
readings, using the exact same load.

Thoughts?


Take care,
Al


----------



## eluminator (May 27, 2005)

The SLAs that you get with a spotlight aren't necessarily the best quality. I've found that when I buy a replacement SLA, it usually has considerably more capacity than the original, and weights a lot more also.

I bought a spotlight from a liquidator on eBay that had probably been sitting around for a year or two. The SLA was just about useless. Hopefully the Harbor Freight ones are fresher.


----------



## Lynx_Arc (May 27, 2005)

MrAl that could work, but you would have to take into account inefficiencies in the inverter/load system including peak power upon startup etc. I figure making a high current resistor would be cheaper and easier for sure as a 1000watt inverter would cost in the range of $60-75.00 and up. 

eluminator The SLA I got in my 500k spotlight looks and works well and harbor freight tends to stand behind its stuff pretty well compared to other places. I have taken stuff back to them with no problems. The sla in my spotlight is a 4.5-5ahr 6v battery and at 7.99 (on sale) the battery alone is worth the price of the whole thing. I stopped by a local electronics supply and they wanted about $16 for a 12v 7ahr sla and about 20 for a 12v 10ahr sla.


----------



## MrAl (May 28, 2005)

Hi Russell,

Yes, that's true.
The high current resistor would have to be 0.12 ohms
and be able to stand 1200 watts /ubbthreads/images/graemlins/smile.gif

Yes the inverter would be more costly, but then you'd also
have an inverter as well as a test load. I guess people
that already have an inverter wouldnt have to purchase
anything, unless they didnt already have a meter.


Take care,
Al


----------



## Lynx_Arc (May 28, 2005)

If you could just make a shunt out of a bar of metal and measure voltage drop across it that would do a lot cheaper.
No luck coming across my source for possible 6v SLAs this week, perhaps next weekend. I can just imagine someone buying a high power stereo and an inverter and tell their wife it is my *battery load* checker...


----------



## MrAl (May 29, 2005)

Hi again Russell,

Yes, i've done that before using brass strips...the 
thicker the higher current rating, but then that was for
a 20 amp shunt, which i could calibrate at 10 amps dc with
my meter. Not sure what i would use to calibrate a 100
amp shunt /ubbthreads/images/graemlins/smile.gif

Yes, that's a good excuse to buy things ha ha /ubbthreads/images/graemlins/smile.gif


Take care,
Al


----------



## Lynx_Arc (May 29, 2005)

I know what I would use to calibrate a 100 amp shunt.. a hacksaw. I haven't looked at what type of shunt material is in cheap car ammeters but I suspect similar materials would work. It may well be a multilayer of materials could be used to work. What really needs to be made for a shunt is a nice BRIGHT lightbulb. This would make both light and a tool but lets see... 100amp @11v approx is 1100watt bulb... YIKES! 
That would be a monster of a light for sure requiring a fairly large holder and reflector and some teflon to fry eggs for breakfast also.

Another excuse to buy something.... battery tester/portable camping light/stove.


----------



## MrAl (May 29, 2005)

Hi again Russell,


Yeah, i used brass and it worked just great, but if i 
built a 100 amp shunt i'd want to make sure it was really
dopping say 10mv at 100 amps, and not say 10mv at 150 amps.
When i made my 20amp shunt i ran a dc current of 10 amps
through it and had it in series with my meter (which only
goes up to 10 amps) and with that i was able to read
(i think it was) 10mv at 10 amps, so i knew 20mv would
be close to 20 amps. With a heavier brass im sure it
would go up to 100 amps without getting hot, but i 
dont know if i would trust a calibration down as low
as 10 amps (or using my 20amp shunt) or even 20 amps.
I'd really like to go to 50 amps for the calibration.
I guess it's not that critical though, as long as i 
used the same shunt each time i'd still get comparative
results year after year. Actually might not be a bad idea.

Yes, 1100 watts of light bulb would be one heck of a 
light, especially at 12v! I guess if you wire enough
headlights up you could get there, but the whole town
would know when you were checking your battery /ubbthreads/images/graemlins/smile.gif
I could see it now..."what the heck is lighting up
the sky like that"..."Oh, he must be checking his car 
battery again!" he he.

Yes yet another excuse to buy a new 1000 watt stereo,
a 2000 watt inverter, a GIGANTIC new multiple Luxeon
spotlight, and another six pack of beer (it should hide
pretty well underneath all that other stuff).


Take care,
Al


----------



## Lynx_Arc (May 29, 2005)

A simpler load on the inverter would probably be a 120v air conditioner at 10amps, that way you would have one cool tester for sure. perhaps an inverter with something like a magnesium aircraft landing light would get close to it. I don't know the wattage or amperage of aircraft lights but I bet they would be a lot closer than high output halogen.

You could also get an old tube radio with high output tubes to suck down the amperage. I see a lot of these 12v portable starter gizmos now... probably most have 12v7ahr SLAs in them. If they weren't so expensive I would pick one up but $24 for one isn't a bargain because I can get the SLAs for about $15 and make my own box for cheap as a plastic box shouldn't add $10-15 to the price. Then you could have a portable 12v supply and a 12v lantern and plug them together, while running lights camera action.... oooops got carried away there.. all at the same time.

I wonder if golf cart batteries are SLA or LA..
I have always wanted a really bright fluorescent lantern with about 2 days continuous runtime, something that everyone would go... UGH! that is bright! and wow them.
There is a time for puny lanterns with infinate runtime and a time for lanterns you can almost get a suntan from.

I saw a cheap 12v tester at harbor freight but I know it was just a voltage comparator circuit with no load to it. It had about half a dozen colored LEDs probably yellow red green etc. I can look at a voltmeter and figure things out about the same for a lot cheaper myself.

I have been thinking of a battery test gadget for all batteries under a certain size.. perhaps up to D cell size
with varying loads you can dial in and LEDs on a bar graph showing how much things are with also an LCD meter too.
I have a cheezy tester I got for $2 that is also a battery carrier that holds 6AAs and 4AAAs. It seems to seperate into 1 and 1.1 volt amounts for green/yellow and belowe 1v it doesn' do anything although a red LED comes on automatically as it is powered by a watch battery or two. I wonder what would be a decent load to test a 7ahr 12v SLA? something that draws perhaps 3amps?


----------



## eluminator (May 30, 2005)

Here are tests of a 12v 8ah battery, Powersonic psh-1280. I used 12v infrared radiators for the load. Some call these things incandescent light bulbs. One test used a 100w bulb, the other used a 55w bulb.


----------



## MrAl (May 30, 2005)

Hi again,


Russell:
Yeah, a toaster too /ubbthreads/images/graemlins/smile.gif
I got a jump pack because it already had things on it like a spotlight,
a cigar lighter jack, and a nice handle as well as two very large 
aligator clips for connecting to a car battery, also with a protection
buzzer to prevent reverse connection to the battery, and also came with
the charger. It was overpriced, but a little convenient.

Didnt you see the 6v/12v battery tester? It was $14 on Harbor Freight;
with 100 amp load tester.

I was wondering how those cheezy little testers worked, ok or not?

eluminator:
Thanks for the interesting graphs.


Take care,
Al


----------



## Lynx_Arc (May 30, 2005)

eluminator
enlightning graphs, it appears an approx 8 amp load results in a little more than 1/2 hour while a 4.5amp load is about 1 hour. I can see the batteries cannot sustain an 8amp load probably due to voltage drop right off the bat.

MrAl
I saw several teseters there. I didn't really look hard at them but I saw a 500 amp 12v, 100amp, 10 amp and perhaps even annother one. I am guessing if you used wirewound resistors you could make one choosing the right value, or maybe nichrome wire via a toaster... yes indeed bring some butter and jam time to test the battery.


----------



## MrAl (May 31, 2005)

Hi again Russell,


Oh yes, wirewound resistors with high ratings would work
too, but the price i think would go above $14 for 1200 
watts worth wouldnt it?
Anyway in case you wanted one i thought i would tell you
about it, and it's got the meter, aligator clips, and what
looks like heavy gauge wire on the clips.

Yeah i bet if you put white bread between the resistors
you could make toast while you tested your battery /ubbthreads/images/graemlins/smile.gif


Take care,
Al


----------



## Lynx_Arc (May 31, 2005)

MrAl
perhaps they need to make a *new and improved* tester that uses a microwave instead of a resistor so you can cook tv dinners while testing batteries, it would be more useful.

I guess the problem with buying a high current battery tester is you wouldn't use it but once every 3-4 years and it used to be places you bought batteries from had the same testers and would check your battery for free, unlike walmarts wimpy computerized *estimation* tester. 

What would work as an *estimation* tester is a computerized battery charger/discharger for SLA/LA batteries. That would charge then discharge and tell you actual Ahr capacity at varying currents. I would guess something like a 1000amp test, a 500 amp test, 100amp test and 10 amp test would do as anything inbetween could be extrapolated if you were to use the battery for some other load. I have been looking around a little at smart SLA chargers but mostly finding 2A+ chargers mostly tailored for LA use.


----------



## MrAl (May 31, 2005)

Hi Russ,

Microwave he he good idea...

I was thinking of using it about once a year just before
winter, because winter shows the batteries true value
once you try to start on one cold cold morning.
Yeah i guess if you dont mind going somewhere to get it
tested that would be good too.

What features would you want in a 'smart' LA charger?


Take care,
Al


----------



## Lynx_Arc (May 31, 2005)

A smart LA charger you could dial in things like charge current and length, add on trickle charging and smart float charging. Essentially you could connect it up and forget it.
It would be able to charge at 100ma and up and float charge perhaps even lower.


----------



## MrAl (Jun 1, 2005)

Hi Russ,

Oh ok, well there is the possibility of building one too
but i guess the more features would require more
circuitry...

Take care,
Al


----------



## Lynx_Arc (Jun 1, 2005)

Have you ever seen the plugin jumper cables where you wire a connector in the grill of a vehicle so you can plug cables in without opening the hood? It may be neat to do that to your car if it didn't cost an arm and a leg so you can either charge the battery or jump start your car or someone elses without messing with the hood.


----------



## MrAl (Jun 2, 2005)

Hi Russ,


Oh no i havent seen those yet. Sounds like it could be
very handy to have something like that hooked up.
I did see a disconnect switch for the battery, which was
basically a heavy duty knife switch with a battery post
terminal (so your battery wire could clamp on) and a
clamp on terminal (so it could connect to your battery).
Seemed like a good idea because you could disconnect the
battery in a second when you want to work on the 
electrical system or something. I think they wanted
something like $20 for it however.


Take care,
Al


----------



## Lynx_Arc (Jun 2, 2005)

I saw those disconnects at harbor freight but didn't recall the price. I saw the plugin socket on a wrecker once and also on a diesal automotobile but on that it may have been hooked to an engine heater. The only thing bad I can think about something like that would be vandals trying to short out and drain your battery causing you to become stranded. It would take a locking mechanism to prevent that so recommending it for some lady may not be a great idea if some thugs wanted to mess with her late at night.


----------



## MrAl (Jun 3, 2005)

Hi there Russ,


Oh yes, he he, that could be a problem. I was thinking
about the disconnect switch hooked up under the hood,
but then you'd still have to open the hood. I guess a
small locked cover would work too. Maybe even a simple
hasp that covers the two connections and locked with
a small lock...should be cheap.


Take care,
Al


----------



## Lynx_Arc (Jun 3, 2005)

I have been looking at those jump/booster/starter gadgets and with the exception of the box it wouldn't be hard to make one for a reasonable price minus the large 8gauge or so cable/clamps. I saw biglots still has the off brand 1200watt inverter for $80, perhaps they will one day close them out even cheaper, I am not sure how much I would use one but for a bargain it would probably be a good size to have around that is if it is a decent quality output.


----------



## MrAl (Jun 4, 2005)

Hi Russ,

If you could pick up a SLA large enough i guess you'd
have half the battle done. I was thinking maybe a cheap
pair of jumper cables only with decent clamps on the ends
and you could cut them in half and make two jumper packs
with only one set! (still need another SLA of course).
If you dont need heavy jump wires it would probably be 
very cheap to install a cigar lighter outlet on the side
or top somehow...that would give you a good plug in 
for devices at least.
The jumper packs have been coming down quite a bit in
price too...when i got mine it was way up there...now
they are down around $30 most places, and sometimes that
even comes with a small built in air compressor.


Take care,
Al


----------



## Lynx_Arc (Jun 4, 2005)

Since compressors cost about $5-10 and battery cables about 8-10gauge cost about the same I cannot quite see it justifying the price of a $10-15 plastic case. Most rechargable spotlights have been going in the $10-20 range or so with batteries that equal or rival cheaper jump packs. I think they have a way to go to be a good *value*. Perhaps the market isn't saturated enough yet with them to drop the price to reasonable.


----------



## MrAl (Jun 4, 2005)

Hi Russ,

Yes compressors came down quite a bit, but they arent that
good either sometimes he he  I was thinking of 
sometime looking for a better one myself, as the $10 unit
i have takes a little longer than i'd like to pump up.
Yeah, we dont have any of those nice cheap spotlights around
here, just the expensive ones (except for one at Costcos).
I'd like to see them come down to $10 myself, and
the inverters too /ubbthreads/images/graemlins/smile.gif


Take care,
Al


----------



## Lynx_Arc (Jun 5, 2005)

My dad just had to take me to the *sidewalk sale* at Harbor Freight. I couldn't resist buying a 50 amp load battery tester there for $9.99+tax, normally I think about $15 (list $27).
I tested my battery and it tested out barely in the 500cca range I am guessing max 600 because they have 300/400/500 bar ranges that overlap. I figure I will use the tester about once every 3-5 years so it will pay for itself. The 100 amp load/starter test one was still at list price of $27 which was too much. I even saw a digital tester at $59.
The tester has something like nichrome wire or a heating element resistor as it gets hot and starts smelling immediately although I didn't hold it on for the full 10 seconds because I was in a hurry to do other things.

Last night we had a power outage here for about 10 hours? I came home to my ups on my computer drained dry, I found one thing I truly need in a power outage I didn't have... a GOOD battery powered fan. I was using a little $1 fan you hang around your neck and it was suprising good but the range of the flow wouldn't allow me to set it anywhere so I could sleep with it on. A fan that could run 10 hours off of batteries is recommended so you can sleep when the A/C is off and it gets sort of sticky. The humidity is now 60% in here vs 45% normally. I saw a fairly nice looking fan at walmart for about $12. This could be a good SLA use.


----------



## MrAl (Jun 6, 2005)

Hi Russ,

Oh, so you got a 50 amp load tester now? Sounds good.
What does it have a panel meter on it that marks off the
CCA's ? Any chance of seeing a pic?
Maybe you should check your battery every year huh?
That's what i intend to do with mine.
Yeah, im wondering what they use for the load now too he he.

Power outage? Yikes, that's nasty. How did the UPS on
the comp get drained...you let the comp run all day?
Yes i agree a good battery powered fan is good to have...
i should get a better one too. How big was the fan you
saw at walmart?


Take care,
Al


----------



## Lynx_Arc (Jun 6, 2005)

The load tester has some sort of wire resistor in a metal frame inside of it, I am thinking it is more akin to a heating element like nichrome wire as it heats up within seconds.
The meter on it has a bar graph that equates 6v batteries as bad under about 4.7v, weak under 6v and ok from 6-7v, the 12v scale lists bad up to 9.2v, weak up to 11.4v and then has overlapping scales for 500, 400, 300 CCA which equate to a minimum of 11.4/500cca, 11/400cca, 10.6/300cca and has a range of charging system OK for about 13v+. The scale goes up to 16v. I believe the charging system OK have low and high red areas but the picture I am looking at is black and white (meter is in the garage).

The fans I saw at walmart were about 10 inches in diameter? I think they ran of 6-8 C or D cells as I really didn't but glance at them awhile back. Next time I will take time to open them up and look but since they have no demo units I won't have a clue to the output and noisiness of them.
I have a battery fan I picked up at walmart for $2 on clearance years ago that has electonic speed pushbuttons and I tried it off 4nimh but the electronics don't seem to allow it to work at that voltage, it works off a 6v SLA so I am going to find a 6AA holder and run it that way instead of 4D cells that way I can use nimh cells. Right now I am eyeballing a way to make my own SLA jump pack, perhaps even with 2 12v SLAs in it instead of one or a 10-15Ahr one so I can run several things at once during a power outage. I figure it may never happen as I am awaiting a *bargain* and thinking about box design or finding a box to put one in. Perhaps a really tough rugged toolbox would work, one with a tray on top you can put adapters and cables etc.


----------



## MrAl (Jun 7, 2005)

Hi Russ,

I looked for fans on the Wally site but that site isnt
that good i guess. I couldnt find any battery operated
fans there. Maybe they have some in the store that they
dont advertise on the site because they dont cost enough.
Maybe if i make it to the store one day i'll be able to 
check for one. If not, i guess an inverter would help
there? Have to check out the efficiency i guess.

If not anything else, 12v computer fans make pretty nice
cooling fans...connect up a whole panel of them 


Take care,
Al


----------



## Lynx_Arc (Jun 7, 2005)

I tried the walmart site in the internet and it doesn't have 1/4 of the stuff in the store on it. I think the problem with an inverter is you are stuck with the loss of power due to efficiency and slaved to 12v only as a power source. I may due the computer fan deal, I may make two models, one for home with a handful of fans perhaps and another portable version with one big one or several small ones.


----------



## MrAl (Jun 8, 2005)

Hi Russ,

Yes, that walmart site is really stupid.
I know there will be loss using the inverter, but that's
the way it goes i guess  Yeah using the comp fans
should work pretty good i would think. Let me know if
you get one built up...i bet it will have high velocity!


Take care,
Al


----------



## Lynx_Arc (Jun 8, 2005)

I could get one with the flashing LEDs on it, so I could use it to see during a power outage also. I think if I use a compute fan I am leaning perhaps towards the 120mm ones as I think they would offer a wider dispersal pattern at lower rpm thus not sounding like an angry hornets nest when running. Hopefully I can get the drain around 200-300ma so I can get decent runtime. I am going to test my current cheap battery fan for its current drain at 6v,7.5, and 9v to see what it does and I have a few computer fans I pulled from fried power supplies and fried cpu fans I will probably test also. If I decide to build one I will either make it run off of AA nimh or a SLA as those are the cheapest solutions to rechargable power. I guess if I was super cheap I could pull apart a $1 personal fan and imbed it in a cheap 4AA lantern.


----------



## MrAl (Jun 9, 2005)

Hi Russ,

Oh yes, i like the 120mm ones too. You can also get big
8 or 10 inch diameter 12v fans too if you like.

I took your advice yesterday, and went to Wallymart
and got a 12vdc fan. It's pretty nice, and cost was
nine dollars. It comes with the cigar plug and an 
on/off switch and a nice big clamp so you can clamp it
anywhere, as well as a permanent mounting bracket if you
decide to mount it permanently somewhere.

Yeah, he he, i have one of those 120mm fans runs off of
120vac and cant stand to hear it running. It's extremely
high velocity (can probably power a sailboat off it)
but geeze, that noise!


Take care,
Al


----------



## Lynx_Arc (Jun 9, 2005)

I, too, went to walmart last night and think I saw a fan. It was in the camping section, a 10 inch box fan that takee 8D cells and has a 12v input jack for $13. They also had a smaller cousin that took 6D cells and had a 4watt fluorescent tube in it too. I saw that 12v fan in the automotive section it was oscillating with a clamp on it and had a switch on a cord coming out ot if I think.

I cannot stand the whine of computer fans that much either, that is why if I used one I may underpower it to run it slower to make the tone deeper sounding.


----------



## MrAl (Jun 9, 2005)

Hi again Russ,

Oh, dang, i forgot to check the camping section /ubbthreads/images/graemlins/frown.gif
I went straight to the auto section to look for the fans.
It's a nice fan anyway though, so i'll probably keep it,
but that box fan sounds even more interesting.
Yeah, that's the one...oscillating yes. I dont use that
though /ubbthreads/images/graemlins/smile.gif

Yes good idea with the fan noise: i did that with mine
but using a couple series (10watt) resistors, and although
it didnt blow as much it was much much quieter!

Oh yeah i forgot to mention i also picked up one of their
portable 6 inch fluor lamps, very small, takes 4xAA's,
and it's just right for an area in my home where i like
to keep battery operated. It was only $6 and change.
It seems to work with my rechar NiMH's so i'm replacing
my tiny (really tiny) mini coleman LED lantern with it,
and it's like 10 times brighter!
I noticed it doesnt start up 'all the way' on low batts,
so im hoping it works out in the long run or else i'll
be looking for a way to boost the batts in it. Right now
it's working well though.


Take care,
Al


----------



## Lynx_Arc (Jun 9, 2005)

regular battery fluoros don't power up all the way or sometimes wait a minute to finally kick in before they go to *high* mode. I have several battery powered fluoros including several F4T5 based, two F6T5, and one F8T5 blacklight.
I saw some 8watt 8AAs for $3.99 and little purple touchlight 4AA 4watters for $2.99 at the BigLots. If you run em too long on low batteries it likes to blacken the ends of the tubes which slightly affects the light output a little.
The 6 inchers I have are 4D and 6D one is a pull cord closet light and the other a lantern/incan/flasher gizmo I got 25 years ago from sears for $10. If you are using nimh and have the room just go with 5 or 6 cells instead of 4.


----------



## MrAl (Jun 9, 2005)

Hi there again Russ,

Oh yes, now that you mention it my Coleman two tube fluor
lantern does that too /ubbthreads/images/graemlins/smile.gif
I'll have to remember that blackening effect and try not to
run it too long at low batt.

So you're saying it should be all right to use 6 NiMH cells
in series to power the fluor lamp that originally uses 
only 4 in series? I guess it works out to about 40 percent
higher voltage...you've done this before?
The mounting space isnt any problem, it's the recharging
that would be...because i have a RS charger that only
likes to do cells in pairs so i cant do 5 cells, i have
to do 4 and then 2 more or 4 and then 4 later.
I'd like to use 6 cells in series, but that sounds a lot
higher...so i'll repeat the question: You've done this
with your fluor lamps before?


Thanks, and take care,
Al


----------



## Lynx_Arc (Jun 9, 2005)

I have used 5 nimh in series on a 4watt tube, haven't tried 6 though but if the cells are depleted enough 6=5 fresh cells
I am running one off 5 1800 nimh A cells from a cell phone pack with no problems 7v seems safe not sure about 8.4 volts though, if 6 cells were left to sit they would be closer to 7.5v which is probably fine since that is about the same as 4 lithium AAs.


----------



## MrAl (Jun 10, 2005)

Hi there Russ,

Oh i see, ok that makes a lot of sense. I'll probably end
up doing something like this unless the 4 cells alone
provide enough run time without dimming to that 'lower'
brightness level that you were talking about.
I want the tube to last reasonably long, as it should.

Did i mention i saw the longer tube mini light too?
It was 12 inche long i think, but it took eight (8)
friggin AA batteries!!! I couldnt see that, unless
i connected it to my 12v SLA JPack which would be great,
but i didnt want one for that purpose, at least not
yet.


Take care,
Al


----------



## Lynx_Arc (Jun 10, 2005)

That long tube light uses an 8watt tube. I have seen those and they are 12v (8AA) but I have one wired to a 9v walwart and it works about the same as wired to a 12v one, most likely because the 9v one floats higher than 9v under such a low load. I typically do not like running anything off batteries that takes 8 of them unless I plan on using it off 12v external power a lot of the time because either recharging that many takes a few hours or eats up a lot of disposables. I like the one walmart used to sell by GE that is kind of large and square with a pull cord and takes 4D cells. It is plenty bright and has a 6watt tube, taking approx 3watts of powwer to run it. I wired mine for a 6v input and run it off a walwart by my bed at night.
I even picked up a cheap 4AA 4watt blacklight which is kind of dim but interesting. Fluorescent blacklights look to be about 1/2 to 1/3 as bright as normal white tubes for usage.
As a bonus this weird black light has a red LED also I guess so you can see without ruining your *purple* vision*

My favorites still are the CCFL lights as they don't seem to mind running way underpowered and are smaller and as bright or sometimes brighter than a 4watt tube. 
I am still looking for an SLA host for my own fluoro lantern. I still have to work on my next fluoro mini lantern, I have the fluorescent tubes, just trying to figure out in my mind how to do the switch, incorporate LEDs into it and use multiple batteries. I want it to run off 4C or 5 subC batteries if possible but will have to make a custom battery holder. I will also have a jack for external 6v power to it (SLA).


----------



## Lynx_Arc (Jun 10, 2005)

I stopped by a closeout place... that lost their lease and got a few deals today. If you are worried about 4watt tubes going I may have a solution: I picked up 8 tubes at 25 cents each plus tax. I could get more they had about 50-100 of them but I don't think I will use these up and need to test them to see color and quality as they are a noname brand.
I also picked up a few cell phone packs and managed to find one that was a sanyo 1300mah that had 5AA flat tops rated at 1350mah. I got an ambigo nicad charger with 15amp 900mah walwart... for 25 cents also. Everything in the store was a quarter so I scarfed up 4 1800mah 6v nimh A cell battery packs and a few more 4.5v walwarts, a few 12v car adapters with 6 plugs, and also a nimh 300mah 3.6v tiny phone cell pack with something like 2/3 AAAs in it. 
Now I know the sanyo packs have 1300mah nimh AAs in them I may go back and see if they have a few more of them, 5 cells for a quarter is a great price, I am charging them to see how they are right now. Anyone need a 6/9v nicad charger?


----------



## MrAl (Jun 10, 2005)

Hi Russ,

Oh 8 watts, ok, that would be pretty nice under my Microwave
counter...hmmm.
I like the idea of the 9v wall wart, and i just happen to 
have a few of those (lower amps like 350 or something).
I could perhaps do the same...put a dc power jack and switch
to switch from battery op to wall wart...would be nice...


I'll have to look around next time i go back to Wallymart
for that square light your talking about...that one sounds
interesting too.
The blacklight sounds interesting too, but is that ok
for your eyes?

What CCFL are you talking about?

I imagine using 5 sub C cells should provide a pretty long
runtime for a small fluor lantern right. Would make a 
great emergency light, or even one used quite often.

Wow, 4 watt tubes for 25 cents each? Geeze, makes me want
to design a circuit to power them to have plenty of
these lights laying around /ubbthreads/images/graemlins/smile.gif
Oh yes, i guess color will have to be checked first...we
dont want any color tint's he he.

Are you saying 15 amp walwart or 15v walwart for 25 cents?
Either sounds good though 

Geeze, you really find a lot of good stuff at these places!
Too bad we dont have much of that around here. Here they
charge as much as possible. Too close to NY i guess /ubbthreads/images/graemlins/smile.gif


Take care for now,
Al


----------



## Lynx_Arc (Jun 22, 2005)

I picked up a few bargains lately. I got 2 8watt f8t5 tubes for 25 cents each as spares. I also got a bunch more of these battery packs that have 4/5AA cells I now have 54 of them pulled out and I soldered some spacers on 12 of them and now they are funny looking 1200mah AA nimh batteries. I also stumbled across a bunch of 2/3AAA nimh 300mah batteries and some quarter sized 280mah nimh cells. I saw a 4v 500mah sealed lead acid phone battery and was tempted but figured it was more trouble than it was worth. 
I may have to sell the 2/3AAA flat tops (out of phone batteries) as I have about 30 of them and can only see using perhaps 6 or so for 2AAA light conversion to LEDs. (inline 2AAA types). 

I had another power outage and used my 6v fan off a SLA I had for 6 hours and recharged both SLAs off my spotlight charger, just took twice as long to recharge. 

I saw dozens of the 4watt tubes, some of them were sylvania cold white also.

The ccfl I was talking about are the ones in lights such as the arcwhite/doublebright/trailfinder, and the coleman micro fluoro lantern. The tube is about as thick as a 12 gauge wire with insulation on it and they can go rather dim without messing up the tube (blackening).


----------



## MrAl (Jun 22, 2005)

Hi Russ!


Oh yes, a 4v SLA doesnt sound too useful really.

You have a lot of power outages where you are?

Those ccfl's sound interesting. How many watts?

My fluor light (that runs from 4 x AA's) is giving me a little
bit of a problem...i want to run it from 4 NiMH cells but the
voltage runs down too fast (mostly because the cells arent that
high to start with after a recharge). This problem means i'd
have to charge the 4 cells every week, even though i dont use the
light for very long periods (a few minutes maybe three times a day).
This means i have to do something to mod the light i guess.
I was thinking of putting a 'boost' cell in series with a pushbutton
switch so that when the batteries get low (which isnt really low)
i could push the switch and that would put another cell in series
so the light starts up properly, after which i could let go and the
light will stay lit normally. This would mean i could use a small
alky cell (AAA) just for starting and it would last a very long time,
and when i need to recharge the NiMH's i'd only have to do 4 not 5.
Five would be a problem because my charger doesnt handle more than
4 at a time.

Take care,
Al


----------



## Lynx_Arc (Jun 22, 2005)

Not a lot of power outages we just had two storms with 50+ mph winds that shook things up and I think the power feed to my side of the block isn't that great as less than a block away they didn't lose power at all. 
The CCFLs are about 4-5watts I figure as they seem to take about the same amount of current as a 4watt tube and are about as bright or possibly unnoticably a little brighter, and they run well on 4nimh also. 
Perhaps your charger isn't putting a full enough charge on the cells as mine puts em between 1.39 and 1.41v and they seeem to do fairly well off nimh but 5 cells do extend the life and brightness dramatically for sure. I don't think 4 alkaline would be much better except from the start perhaps the first hour of runtime may be slightly brighter till voltage sags below 1.4v. You will probably find using your booster cell you will want to leave it running all the time due to the increased brightness when it is kicked out. If you are willing to risk it try using 6 nimh if your charger isn't getting them a full charge, if you fry the tube I got 8 spares and for a little while longer can get dozens more for cheap.


----------



## MrAl (Jun 22, 2005)

Hi Russ,

Oh i see. I guess it's good to be prepared in any case.

My charger is putting out the correct 'ending' voltage
maybe the RS cells run down too fast, but then the 
voltage is 1.23v when they dont work any more, so i
assumed it was a cheap fluor light?
It puts out a decent amount of light however.

Maybe i'll switch to a 6v SLA as i have no way to charge
six cells at once and i'd hate to dedicate that many cells
to one little light anyway...im not sure yet however.
I'd use a wall wart in a heart beat but i'd like this
light to be stand alone run from batteries.

Maybe this is one of the reasons ive been turning to white
LED's for everything. They arent as fussy  Well, ok
maybe but in other ways that seem easier to deal with.

I like this light so much though, as it puts out quite
a bit of light for such a little thing -- just right for
what im using it for.

The previous light was a two LED tiny coleman lantern,
hardly can be called a lantern at all because it put out
such little light, but the batteries lasted a whole month
or more.


Take care,
Al


----------



## Lynx_Arc (Jun 22, 2005)

Yea it takes a bunch of 5mm LEDs or a few luxeons to compete with even a 4watt fluoro for sure and pricewise there is not competition at all. I have two 4watt lights hooked to some oddball rechargable batteries and I may not even use them except in an extreme power outage when all my other batteries are drained (yea, right).

I like the idea of SLA driving fluoros for sure as the tube is larger and the battery doesn't dwarf the rest of the light like LEDs.


----------



## MrAl (Jun 23, 2005)

Hi Russ,

Yes it does take a bunch of LED's to equal a single fluor
tube he he, or at least a bunch of money /ubbthreads/images/graemlins/smile.gif

You reply also brings up the question...

"Is it really possible to drain ALL the batteries in
any true flashaholic's cache?"

hee hee

The more i think about this the more im leaning toward
a small SLA at 6v. Nothing else seems to be quite as
nice...

1. If i use alkies, i have to keep buying them.
2. If i use rech alkies, i get lower and lower run time
quite soon.
3. If i use 5 or 6 NiMH's i have to get a new charger.
4. If i use an SLA, i have to purchase one :-(
5. If i stick with current 4xAA NiMH's i have to recharge
once per week (yuck).
6. New idea: step down converter with my big 12v SLA ?
would mean the 300ma drawn by the fluor would only
draw about 150ma from the 12v SLA which is hardly a
load at all for that thing!
I'd have to run a concealed cord however.


Take care,
Al


----------



## Lynx_Arc (Jun 23, 2005)

I just found a 6AA holder and took one of my fluoro touch lights (4watt) and ran it off of it with seemingly no side effects. It was drawing about 375ma at approx 8v input from 6 2300mah energizer nimh.
I enjoy my rayovac 1 hour charger although I have to charge my 2300s twice due to the timer shutting off before they are done. 
I still like SLAs but with all the AAs I got I either need to figure out uses for them or start selling some of the 4/5AAs as I probably wont use 54 of them at once and keeping them topped off is silly. I may wire a bunch together and get myself something like a triton later so I can charge them in packs.

As far as the step down for 12v SLA, just buy another 4watt light and wire em in series for it.


----------



## MrAl (Jun 24, 2005)

Hi there Russ,

Oh wow, so that means we know now that they will run off
of 6 cells...that's great.
I'm going to try mine off of 5 cells pretty soon. I just
charged my 4 cells about two days ago and already the light
is turning on slow, which means it soon stays in it's
'low output' mode, so im hoping that 5th cell will start
it up better.

Yeah i like the SLA's too, but im not in a hurry to spend
$14 just to light that light when i have those 4 aa cells
i wouldnt use for anything else /ubbthreads/images/graemlins/smile.gif

Wow you got 54 of them,,,geeze  That's a lot.
Are they NiMH's ?

I like the dual 4 watt light idea, but i sort of liked
the light output from one now, and that would mean it 
would be eating 300ma from the 12v instead of 150ma (or so).
That's not too bad either i guess though.

Take care,
Al


----------



## Lynx_Arc (Jun 24, 2005)

yes, 54 4/5AA nimh 1200mah cells. I got some brass screws and soldered them onto the cells to extend them to AA size which took several days to accomplish. I even tried my 6AA cell holder with my 6v fan which didn't work with 4AA nimh probably do to the electronic switch on it and it worked fine. I even tried a 12v CPU computer fan off them and it worked also. I have some cell phone packs with 2/3AAA in them I am planning on using 3 inline and putting an LED in my pelican mitylights direct driving them, perhaps I may put 3 LEDs in one. Now I just have to figure out how to use too many batteries. I also have 20 AA 700mah nicads and 20 A? 1800mah nimh cells in phone packs sitting around. I am still *thinking* about the nimh 280ma coin cells I got and can get a bunch more but unsure if anyone would want them. They are about 2-3 times as thick as a 2032 and a little bigger I think. I guess you could put 50 of them in a flashlight or something... 
I think my next mini lantern may be a 6AA/5subC/4C cell lantern if I can figure out how to manage it, maybe differing power connectors with bypass switches I can flip when voltage drops lower. I like the size of the 6AA holder and it has a 9v clipon to it costing me $2.25. 
I am still looking around for cheap SLAs.. preferably largers ones now I have dozens of spare nimh, Maybe I will get a 8 or 10 cell holder for AAs.


----------



## MrAl (Jun 25, 2005)

Hi Russ,


Wow, sounds like quite a job soldering all those batteries.
Are you sure it's ok to solder those types?

Oh yes if you have plenty of NiMH's around it makes sense to use them
but getting holders. I would do that myself too.

I finally got to try the fluor light with 4 x AA cells and one extra
alkie in series to temporarily get the light to start correctly, then
disconnect the extra cell and go back to 4 x AA and it works! The 
light starts out by startup up 'normally' with only a very slight delay
before it jumps to full output, then on taking off the 5th cell (for
the starter boost) the light dims slightly, but stays in the high output
mode. This means either using a pushbutton 'start' switch or making
a circuit to do it will allow running the light on 4 AA cells even when
they die down pretty far. I simulated very very low batts by using 
a resistor in series, and low batt simulation was easy because the 
batteries were really a little tiny bit low.

One question for you...

You said prevously that the tubes 'darken' or 'blacken' a little when
they are run at low batt and they dont get to start up normally (to that
second level of brightness). What i was wondering was, do you know
how badly the tube will darken and how bad it will affect the light
output after say a couple years? I was asking because i realized that
the light does work on that lower level but it must be drawing more
current (didnt measure it yet) and it just doesnt get as bright (about
50 percent dim).


Take care,
Al


----------



## Lynx_Arc (Jun 25, 2005)

The lights I have with darkened tube ends seem to work about the same as normal ones but the little bit of light they may put out near the ends is blocked off. The darkening is about 1/2 to 3/4 of an inch from each end approx and mostly looks bad. I think the darkening may be when you have the light running and let it keep on when power gets too low, not necessarily by trying to start it with weak batteries.
As for current draw, I believe if it doesn't have the voltage to kick into high power mode it just runs at a lower current. If the batteries are too weak to kick into high mode it may lead to the darkening. I have a few extra tubes if you want to experiment I can send you a few. 

Another note: I finally got ahold of the guy with all the SLA and headlamps and picked up a bunch of stuff today. I got 4 of those nightblaster 3AAA cheapo walmart cliplights in white and one in red. I got a 2white/1red/1incan headlamp that uses the same 3AAA cartridges, I also got a cheap 4AA headlamp using the 1/8 jack input and 2 RED xenon/LED headlamps that both have 6v SLAs in a nylon mesh pouch.
I also got a BIG 12vdc powered fluoro lamp with 1 white and one black F15t8 tube and a car lighter cord on it. He told me he has some 12vdc SLAs that are square (I think they could be batteries in lights like the thor). As soon as I get a paycheck coming in I am signing up for paypal so I can sell some of this extra stuff I got.

Oh, I also picked up 2 12v H3 130 watt bulbs and have 3 6v 20 watt halogen bulbs. I found out my cheap walmart mossy oak 4AA flashlight has an aluminum lense in it.. go figure.
Maybe I can put the lense in another light and use 6AA nimh. I hooked up 6AA 1200mah nimh to the 20watt bulb and it was uber bright, also hooked it up to my spring top SLA and it was about as bright.

I will probaby have to wait a month or so for the guy to come back into town again I wanted to buy a lot more stuff but resisted as I got so many headlamps now it is rediculous. These red lensed ones are interesting, I will probably sell them both.


----------



## MrAl (Jun 26, 2005)

Hi again Russ,

The darkening you describe doesnt sound too bad so i wont
worry about it for now.

From all the stuff you seem to be purchasing maybe you 
should get TWO paypal accounts /ubbthreads/images/graemlins/smile.gif

Thanks much for the offer...i'll see how things go now
that im experimenting a little with the light. So far
the whole problem is starting to look like it could be
due to a SINGLE NiMH cell RS brand /ubbthreads/images/graemlins/frown.gif becuase when
i replace that one cell with an alkie the light works
again. Of course it reads lower than the rest too,
so maybe i'll test that cell at some point. Meanwhile,
i'll see how long the light lasts with a single Alkie
and 3 NiMH's and go with that if it works. If it doesnt,
i decided to take your advice and go with adding another
cell (outside the light wired in) and i'll make that one
an Alkie. This way, i'll run down only one alkie cell
and three NiMH's. I'll have to implement my 'diode'
idea to trick the charger into thinking it's got 4 cells
in it when really only 3 (posted somewhere else in this
forum).

What else did you want to purchase? Sounds like you got
quite a bit of stuff already, but you know maybe you could
turn a profit from all these finds? Maybe advertise right
here on CPF.


Take care,
Al


----------



## Lynx_Arc (Jun 26, 2005)

I got a bunch of junk, I picked out two things and asked what they were and got... I dunno. So I bought em and got em home and put batteries in em and said... neato. One is an 8 1/2 inch CCFL straight tube light with reflector powered by 4AA batteries, the other is a SMD blinking yellow LED powered by 3 LR44 batteries in a yellow textured wand that ia bout 6 inches long. I also picked up a few more headlamp parts as one xenon bulb was burned out and he didn't have any spare bulbs for it. I found out the two red headlamps the red lens is removable which is neato. I figure I wont see this guy till nearly september but if I get my paypal up and going I may contact him and see if I can pick up some stuff for CPFers. He had several 6watt 6D cell lights with 2 or 3 tubes in em 1 white and 1 or 2 blacklight bulbs. I now have four of these 2white/1red/1xenon 3AAA headlamps similar to the rayovac ones, one of which needs the rubber pushbutton cover fixed and 7 of the nightblaster cliplights.. 5white/2red. I hope I can pick up some nice 12v SLAs then although I am unsure if they would be worth selling and shipped via mail due to the weight. I have 3 6v SLA based headlamps now, if they had glass lenses and metal reflectors I would swap out the xenon 5 watt bulbs for these 20 watt halogens (hoping the wires dont overheat).

It is possible if your fluoro is dying too quickly you have a weak nimh cell, I would measure them all before charging next time as I have had two nimh pulls that were weaker than the others causing the whole group to die about 40% faster than usual.

I bought some of this stuff to give away as gifts and sell later. If I can get some seperate SLAs I will probably sell one or two of my SLA based headlamps and/or mod one of them.
I can probably get dozens of the cliplights, perhaps even red ones, I also got a box of junk I am fixing for him that is a bunch of 2AA and 4AA incan headlamps, maybe good hosts for mods. 
I pulled out about a dozen burned out PR based bulbs I can use to mod for LEDs of which I just received 100 white LEDs in the mail I bought cheap for fiddling around projects and I am waiting for my 10 nichias although I have no idea what I will use them for yet. I can see wiring up a bunch of my cheap LEDs in an array to hook up as a floodlight in a headlamp and attach a belt pack SLA to it.

I also picked up a gadget with a cigarette lighter socket hooked up to clip leads so I can later power 12v stuff from a battery. I have several lighter adapters that go from 1.5 to 12vdc I can use to power all sorts of stuff like walkmans etc.
I saw somewhere that USPS has some sort of flat rate package you could almost stuff gold bars in and mail cheaply.. wonder if SLA batteries would fit well in one...


----------



## MrAl (Jun 27, 2005)

Hi there Russ,

Oh yes, i think you'd be doing a great service if you could
get stuff for CPF'ers and resell to them, and it sounds like
this guy has a lot of stuff CPF'ers would be interested in.

It does look like the one cell is making them all look bad,
something i talked about a long time ago right here on CPF.
I had measured cells in the groups they were purchased in
and noticed there was always one weaker than the others.
I'll have to look up my notes now to see if this was the
lowest measured cell in the bunch when i first tested them.
Maybe i'll charge it up with a small test circuit and
see how it performs after it's been charged by itself to
full capacity.

The floodlight headlamp sounds interesting. I have a HL
with only 8 white LED's and it puts out a lot of light,
so anything above that i would bet would be really great.

About you're conversion outlet and related stuff...
you might consider making them for CPF'ers too and resell.
I know there were times when i needed a 12v cigar type 
outlet and didnt have one. Might need another one at that
in the future too...

Do you rem what USPS calls that package?


Take care,
Al


----------



## Lynx_Arc (Jun 27, 2005)

One cell that is weaker will tend to discharge and when it is depleted it either reverses or essentially drops out either increasing ciruit resistance or essentially makes there only be three cells there.
I have a 12 x 26k LED headlamp but the LEDs are not pretty. It is rather bright but I have a host now that can handle 4AA batteries with more room I may be able to go with 24 LEDs resistored, perhaps even a variable resistor if I can find a decent one. 
I think someone called it a flat rate package. I am guessing it is a certain size and weight doesn't matter unless you want to ship a black hole or something I would guess you could fill it with lead tire weights if you wanted? I saw someone say it was $7 something... under 8 bucks. It may be a good way to ship a few small SLAs depending on the package/box size. If it is just a folder or flimsy box it may not be usuable for heavy stuff. Perhaps someone will chime in before I make it to the post office this week.

I fixed the one 3 LED/incan light that wasn't working because of a bad rubber boot over the pushbutton by sticking in a small hex nut in place of the worn out rubber part and it works perfectly. I am going to keep spare parts perhaps someone will need a new headband or plastic swivel mount thingy. 
The 12v clip on lighter outlet you can get for about $3 at harbor freight but I got mine for cheaper than that, he had some that were fused also and a 16/2 extension cord also there. I took my 6cell and 4 cell AA holders and hooked them together and was running a computer fan with em, but the fan was too small and took too much current for the output IMO, but it was a CPU cooling fan. 

I also bought a new tip for my 50 watt ungar iron for almost.. *UGH* $6. They had a weller 60 watt iron for about 30 bucks I went.... hmmm. It looked considerably larger though and the tips were larger. I saw some isotop batteries for 23.00 and told the gal at the counter I just rip subC nicads out of packs for mine at $6 a pack.


----------



## MrAl (Jun 28, 2005)

Hi Russ,

Yes the one cell is making the whole pack look bad.

24 LED's ought to make a really nice light /ubbthreads/images/graemlins/smile.gif

That package doesnt sound bad at all, for heavy stuff.
Would be a lot cheaper than UPS.

Oh three bucks for one of those outlets doesnt sound bad.
The only thing i dont like about HF is their delay in
shipping here due to their 'bulk' shipping. Oh yeah,
that reminds me...i bought one of their automobile
battery testers...the small 100Amp model. It works 
really great and has a very nice large meter on it.
But it took two weeks to get here /ubbthreads/images/graemlins/frown.gif
The resistor inside is a 1200 watt job he he.
Gets hot as a toaster in 10 seconds flat /ubbthreads/images/graemlins/smile.gif

Wow 60 watts...that must be one big soldering iron...


Take care,
Al


----------



## Lynx_Arc (Jun 28, 2005)

I was considering a 2D boosted 24 LED light but I am having second thoughts now since I have a boatload of AA and AAA rechargables and Alkaline Ds are about 75 cent to over a dollar each. Perhaps I will use a 4AA host and figure out a switch to power differing amounts of the LEDs from perhaps 6 to 24 in group three stages. I figure at spec it would draw about 500ma which would give me from 2-4 hours runtime depending on which nimh I put in or alkalines.

I accidentally dropped my battery tester and broke the clear meter cover so I need to glue or epoxy it back somehow. The meter adjustmant gadget is broke also but that is ok. They do need a slot for toast in that bugger so you can use the heat generated by it for something.... perhaps they can make a frying pan version tester too. /ubbthreads/images/graemlins/grin.gif

The 60 watt iron was bigger but not overly huge. My 50 watt ungar looks a normal size with a 1/8 inch screwdriver tip in it. I could have gotten a conical tip at RS for cheaper but I like the screwdriver ones for this iron as I tend to use it to solder large foils and parts at times. I think I will spring for either a nice soldering station or a princess size pencil iron around 15 watts. They are handy for small stuff. I have a two stage soldering gun that does something like 100/200 watts if I need to really do something and I suppose I can use the battery tester and throw the parts and solder in the hole.

On another note I made it to the post office and picked up some flat rate boxes and the envelope. Looks like one of the $7.77 boxes is big enough for something like a large sweater, the other big enough to put perhaps 4-6 small 12v SLAs... perhaps 7-10Ahr. The envelope is 3.85 and a common shipping size you can put anything in as long as it seals properly. Looks like the small squarish box is the best deal as with a little reinforcing you can ship some heavy stuff in it cheaply.


----------



## MrAl (Jun 29, 2005)

Hi Russ,


Dropped the tester? Sorry to hear that...Maybe some carefully placed model airplane glue might help.
Yeah a fry pan / toaster over version he he.

Hey those USPS packages sound interesting. Several small 12v SLA's still weigh in quite a bit.
That would be a good price for shipping those right?


Take care,
Al


----------



## Lynx_Arc (Jun 29, 2005)

I am guessing if could hold 20-30 lbs of small SLAs which would be a bargain because USPS charges about $2-$3 a lb I think for shipping which would make a 10 lb box cost $20 so it could save as much as $30 if you pack it full making sure to reinforce the box or put a slightly more robust smaller box inside of it. 

I can fix the tester, all but the adjustment thing as I just broke the bottom edge off which doesn't affect the viewing area. As often as I will use it, it doesn't bother me that I broke it because using it a few times will pay for the $10 investment. I did see they had float chargers for $5 on sale but I don't have a use for one at this time and would rather have the $5 to buy stuff with instead. 

I am guessing if you sold a mess of heavy aluminum flashlights the flat rate box could be a great thing. It is a possibility some vendors could actually profit from charging regular postal rates and send stuff in flat rate boxes if they were unscrupulous.


Oh, my tester is only 50 amps but that should be enough to get an idea of a bad battery. I went shopping and picked up a few halogen 2,3 cell pr bulbs (streamlight) a few pelican light modules and a 75 watt 12v GE bipin bulb (red package).
Perhaps a hotwire nut will want it or I could come across a 12v SLA and make a mean flashlight with it.


----------



## MrAl (Jul 1, 2005)

Hello again Russ,

OH yes, i'm going to have to keep that package in mind
for future shipments. It's gotta be a cheap way to ship.

50 amps is probably ok. Wow, 75 watts bulb? That things 
going to get super red hot /ubbthreads/images/graemlins/smile.gif What are you going to use
to hold it?

I found that with my fluor light i've been talking about
it looks like either one more or two more cells are 
dying too fast. Crummy RS NiMH cells /ubbthreads/images/graemlins/frown.gif
Looks like i'll have to test them all AGAIN. I tested them
very carefully when i first got them and only charged them
about 5 to 10 times now, so if they are showing much reduced
capacity now i'll never buy RS cells again!


Take care,
Al


----------



## Lynx_Arc (Jul 1, 2005)

I am not sure what to do with the bulb although I have a ceramic socket for it that a 6v 20watt bulb goes in that is mounted on a metal plate. I thought about trying to put it in a headlamp but I doubt I could run it for more than a few minutes at a time and would have to put in a metal reflector and glass lens. 
The way I *test* nimh cells is to put em in something run em down and measure the voltage of each one compared to the others immediately after use. I haven't bought RS batteries since the 70s when they had the free battery club. I have found similar problems though with some of my cell phone pulls but I just took the weaker cells and matched them together by putting one red dot on the end each time they wimped out so I have two red dot cells in a headlamp that runs about 2/3 as long as better ones. That is one major advantage of SLAs..... you don't have to worry about one weak cell unless you abuse the battery and then the battery is toast if you do. Makes you wish you had access to that Lacross charger to test those batteries doesn't it?


----------



## MrAl (Jul 2, 2005)

Hi there Russ,

I tried a smaller bulb in a long alum tube and it got
the whole tube hot after a while. Those things REALLY
get super super hot so i tend to stay away from them.

That's an interesting way to test the cells. The way
i do them is to put a load recommended by the manufacturer
and log the voltage and current and from that calculate
the storage capacity in Amperehours. If it's much lower
after only 5 to 10 charges i'll know the cells are 
defective. I guess a comercial tester would be nicer
yes as that would save the trouble of setting up the
meters and the load and all.

Im still thinking about going SLA with this thing still 
Would be really nice. I also just picked up another 8
LED flashlight last night so if all else fails i'll
probably convert that lamp to LED's and go with NiMH's 
again.


Take care,
Al


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## Lynx_Arc (Jul 2, 2005)

Last power outage I ran two things off SLAs, my stereo and my fan. All the lights were run off nimh. I have 1 12v SLA and 5 6v SLAs now to play with. I have a lot of nimh AAs but keeping them topped off would be a nightmare with only one charger so in a power outage the SLAs will probably power a lot of stuff with the nimh powering lights. I also have 20 nicad AAs in 4 5 packs and 2 6/7.2/9v chargers I haven't tried yet for nicads only. 
I made a new PR based LED bulb with a 22 ohm resistor and 3 white LEDs out of the 100 I received and it is bright running off a 6v flashlight. I am going to make a few more of them over the next week. I have 4 taplights with a weird circuit in them that has a 555 timer and one transistor that turns the light off after 1 minute. I put a larger cap on it and got it to run for 15 mins but found out after a month of trying it the circuit has a constant 5-15ma drain on it. I am wondering if it can be rebuilt with a mosfet in it to reduce the idle current to microamps instead as the circuit handles 500ma and would be ideal for other things if not for the large drain. It was draining 1500mah AAs dry in about a week just sitting there.

I have an 8 LED 3AAA flashlight I converted to 26k LEDs and it is pretty nice while the runtime more than doubled on nimh. Current drain went from 390ma to 190ma while it is about the same brightness. I am looking for some cheap integrated boost circuits I can get for about $1 each that will run at least 250ma load on them as I have been using cell phone booster chips and only have two left. 

I wish 4 and 8v SLAs were more popular as they would be ideal to run LEDs off of, 6v ends up having to use a regulator and either dump the excess as heat or go with a Dc/DC inverter to save some of the excess power.


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## MrAl (Jul 4, 2005)

Hi again Russ,

Yeah, i have a number of NiMH's and keeping them all topped off isnt
all that easy, as it means recharging quite often...it's a pain because
you have to remove the cells from the device each time and then put
them back in. That sounds easy but not when you have to constantly
do it over and over and over and over...again /ubbthreads/images/graemlins/smile.gif

Hey, that auto-turnoff thing sounds very nice...would be very handy for
my fluor light too. 555 timer sounds cool, but yeah you dont want a
constant drain for something that isnt running. Dont see why there
would be a drain after all it supposed to turn off, so maybe you could
look into the circuit or something. If you could post the schematic 
we could examine it in detail to find out what's drawing that current.

I'm thinking of converting my fluor light to maybe 8 led's also if all
else fails in getting it to work the way i want it to. I've now tested
my RS NiMH cells and one runs down very quick...down to 0.9 volts in
about 2 hours with only 300ma load, and it's supposed to be 1800mAh!!

BTW, the Zetex circuit can run 250ma easy, but it's more than a dollar.

Did you ever measure a 6v SLA battery after it's been running something
for a while to see what the terminal voltage is? Is it 5.9v or more like
5.0 volts?

DC/DC converters are really easy to build for going DOWN in voltage
(you know, step down 'buck' converters) but you'll have to shell out
a few bucks to build one. Using National's 'Simple Switcher' line
makes building a circuit pretty easy...i know have several of these
types built up and running various things like my scanner.

Have a happy 4th!


Take care,
Al


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## Lynx_Arc (Jul 4, 2005)

Lets take a look at the components of that taplight timer circuit. NE555N 8 pin IC, K 012 C8050 C standard looking transistor a diode (black with silver end band), a 47uf electrolytic cap, and 3 resistors a 2200ohm, 100kohm, 1megohm.
I figured out the capacitor holds a charge that is depleted by the circuit and if you add capacitance the timer will go on longer (I added in parallel a 470uf cap and got about 15 mins vs about 1 min. The circuit is toggled on/off via a capacitance touch switch the taplight hits when pressed.
While *waiting* for the circuit it consumes 4-15ma. 

8 LEDs cannot compete with a 4 watt fluor at all, you probably need close to 2 luxeons for that I figure.

As for the terminal conking out voltage on a 6volt SLA I would guess deep discharge would be around 5v as similarly a 12v car battery conks out around 10v or so it seems.

A DC/DC buck circuit would be ok if you are going down a decent amount of voltage as I figure the boost circuits lose 50% efficiency (cheap ones) the buck circuits probably do nearly the same so dropping 2v you save 1volt of energy, dropping 12-4v you would save about 4v times whatever current is my *guess*.

I made my second new 3LED pr bulb today and am figuring out things about cleaning out glass bulbs, grinding the lips off the 5mm LEDs and lining them up to solder. It seems if you get the height right it can get and focus some of the side spill off the LED making patterns depending on the parabola focus. I am using 22ohm resistors with 3 LEDs and 4AA nimh but it should handle a 6v input while driving the LEDs around 35-40ma each. 

If your RS nimh is caving in after only 2 hours it is a dud for sure, you should get 4-6 hours or so I figure. I have a theory either some cells are weaker or the internal resistance differs making them give up the ghost so to speak earlier than the others. I figure your weak cell will cave in even with LEDs on it.

Right now I am in cheap light mode. I have 2 mc34063 circuits I got for $1 each and have inductors plus some torroids I got for 95 cents each prewound the size of a nickel, the store I get those from have about 10000 of them in bags of 100 so if they work for everything I have access to a near infinite supply.

I have a broken scanner I may yank out the CCFL tube one day, (I think they have CCFLs in them).

You know it is getting late when the informercials take over, not having cable tv kind of sucks but gives me more time to write nonsense here.

happy fireworks buying day


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## MrAl (Jul 5, 2005)

Hi Russ,


Ok, the 555 is probably eating that standby current then, so the
only way to improve is to go with a new circuit or else try to
mod the present one by disconnecting the 555 completely once the
time is up. It's probably easier to have a MOSFET biased on
with a large value cap connected to V+, with a charge resistor
to ground which causes the gate to charge lower and lower as 
time progresses, turning the MOSFET off at a time determined by
the RC time constant. This wouldnt be a super accurate time 
setting, but should be close enough for turning LEDs/Bulbs off.
The standby current would then be roughly the leakage current
of the capacitor, which is wayyyy lower than most other parts.
Almost any N type MOSFET would work too, with the lower 'on'
resistance models keeping the turned-on eff high.
To reset the circuit, you could short out the cap with a switch
and small value resistor in series, or kill the power and have
a diode shunt the gate to ground.
New circuit connections (N-MOSFET):

Drain to ground
Source to load
other end of load to V+
Cap from Gate to V+
Large resistor from Gate to ground
If reset on power down, diode cathode to gate anode to ground (1N4001)
If reset on pushbutton, switch across cap with say 100 ohms resistor in series.

Yes you're right about the 8 LEDs not equal to the fluor, but i think 8 would
still provide enough light for my purpose. Trouble is, the fluor light
spreads the light out nicely on the counter below, while the LED's have that
very directional output beam...what to do? Well, im not proceeding with that
until i try some more tests with the fluor light first. Im trying regular
alkies to see how it works with them. Im wondering now if that light draws
very high peak currents (typical of some boost circuits) and that's whats drawing
the batt's down so fast (except of course for that one or two RS cells which are
truely bad).

From what you say, it sounds like a 6v SLA would work wonders with this light!
Maybe i'll have to try one just to see how well this combo works even if something
else works too!

I can get at least 80% going from 12v to 6v im pretty sure, with the Simple
Switcher from National. That should be good enough. Im not sure i want to 
dedicate my big 12v SLA to that task however /ubbthreads/images/graemlins/smile.gif

Oh so you're making your own LED bulb replacements? Sounds cool. Im sorta
into higher number LEDs now myself though...like 6 to 8 or more in one light.
Overdriven the output is pretty darn good!

Yeah i've proven now that the RS cell is bad, and maybe another one too.
They are getting closer to the garbage can day by day /ubbthreads/images/graemlins/smile.gif

Wow that many inductors? Do you have any spec's on them like uH value and
current rating and saturation level? For that price wow.

My scanner has a long fluor in it. Not sure what type it is.

[added]
Oh BTW, the power down reset wont work unless there is
a decent load on the supply line so maybe better to go
with the switch.


Take care, 
Al


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## Lynx_Arc (Jul 5, 2005)

Sounds like a messing fixing the countdown circuit, I was hoping to swap out a few parts but looks like a complete redesign. I have one taplight with an on/off switch now running 4 LEDs that are pointed backwards at the white reflective plate inside they are driven at approx 40ma each by nimh and light up the bathroom nicely. 

I had a few weak nimh I am guessing perhaps 20% less capacity within a group I culled out and replaced with others and things worked fine. You could take the weak ones and put them together and pair them up using them in perhaps a 2 cell light if there are two of them. I have done that myself and they work fine now although the runtime is less since they are more *matched* they both drain down about at the same time. That is one problem with a decent drain on nimh multicell packs (nicads too) is weak mismatched cells. I am guessing cheap drill motor packs fail because the weak cells end up dying fast and after a few hard discharges they even reverse which perhaps weakens them more or ruins them.
I have so many AA nimh now I am having to invent ways and make new lights to put them in. I used to have excessive amounts of AAAs but have recently got about 6 new 3AAA headlamps/cliplights so I yanked all my AAAs (with adapters) out of AA lights and I now have about 3-4 dozen AAs extra of various sorts laying around.

I don't have that many inductors, I can buy them as they have a ton in stock. I am not sure of the inductance but I am guessing it is similar to the torroids in many high output luxeon based 1-2 cell boost lights. I did an experiment on an accent lantern last night... I hooked some clipleads to the LED on it to 6 26k LEDs and then wired up 2AA nimh to the base (it normally runs off 1D cell). The boost circuit put out about 80ma to the 6 extra LEDs which makes me think it would run 4-6 cheaper less efficient LEDs
off the same circuit making for a brighter lantern. I am thinking about an adapter to run 2x2nimh AAs now for one.

SLAs are nice for any voltage compared to mismatched nimh or nicad packs. I haven't had too many bad nimh cells but when you find weak ones in a bunch they have to be matched together and kept seperate or they are useless. 

The 3LED PR bulbs are nice because when I grind the lips off the LEDs they slide in place of normal krypton bulbs in 3-4 cell lights without any modding at all, makes for a quick easy mod. I have one light I put a 4LED bulb in I had to grind the reflector out to fit it which wont work on lots of lights due to they have a metal holder attached to plastic reflectors that cannot be ground out larger for the LEDs.
I looked around to buy some 3x5mm LED PR bulbs and noboby makes them. They make 3x3mm bulbs but the 3mm LEDs are not as bright as higher output 5mm LEDs. 

I had an idea for a resistored/direct drive setup that requires a test button/switch telling you when the voltage is low enough to bypass the resistors limiting the current.
I haven't figured out if it is easily (cheaply) possible though.

I have 4 6v SLAs and am considering a high output LED/fluoro lantern with either a gob of 5mm LEDs, a few luxeons, and/or a few fluoros possibly ccfls. If I go with a lot of LEDs I may look into a current limiting or DC/DC buck circuit to increase runtime/efficiency. I think the marriage of SLA with LED is nice and if I can get some cheap 12v SLAs I will make a few lanterns with them instead due to easily charging from 12v auto systems.


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## MrAl (Jul 6, 2005)

Hi again Russ,


It shouldnt be too hard to build up that new circuit with the Mosfet,
and after all there's only three parts plus maybe a PB switch.

I guess i'll have to do that with my RS cells too, instead of throwing
them all out i'll match them up with other cells of similar *real* rating.

It's nice to know what specs the inductor have so you can get an idea 
how well it will perform in a circuit, but if you have something running
you could measure efficiency and get some idea from that too.

Oh i didnt know they used smaller LEDs in the PR bulb replacements. I
thought they used the regular LEDs. I'd like to see the larger ones too.

The low voltage bypass idea sounds good. Im not sure how this could be
done, maybe with a circuit that measures voltage like a comparator
circuit. The output could drive a small LED to indicate when it's ok
to bypass.


Take care,
Al


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## Lynx_Arc (Jul 6, 2005)

That may be a future project, perhaps even just replacing the parts on the board I have with other ones would work also, but right now if I cannot fix it for a dollar it is on the back burner for awhile.

I have a theory that perhaps cells with lower capacity have differing internal resistance causing them to let go of their current/voltage faster perhaps this causes them to appear to *die* before other cells. This idea has no foundation it is just a whim.

I am guessing the inductor is about 10uh and fairly effecient. I have one in my 12led headlamp and it isn't too bad.

All the LED pr bulbs I have seen have 1 or 2 5mm LEDs in them but when they go to 3 LEDs they use 3mm. I suppose it takes too much labor to do what I have done grinding the lip off of them and jamming them together. I *may* make a 7LED bulb in similar fashion and ream out the reflector of the light it goes in if I can find one that would work right that way. I also have an extra headlamp that has a 1/8 jack into it that I can plug on of me 3 SLAs into or my 4AA packs or even my 4D pack I may consider modding with a bunch of LEDs perhaps.... but I like the PR bulbs because they are quick and dirty mod if you can find a 4AA flashlight to put them in.

I would *guess* the caparator would need two LEDs. One to keep lit up until the voltage drops too low for it and another to keep lit up at the voltage needed for the switch over so you will know if both are on the voltage may be too high but if one is on it is just right and if none are on the voltage is under what is needed perhaps. You could even have a switch to kick in a 2 cell boost circuit and use the same tester and set a voltage for that level also. One thing I have found though is using non rechargables can hit the LEDs with a lot of current due to *recovery*. I have led a light sit for a day that would be dim and it was bright for a few minutes then dims again. This higher initial voltage could be harmful for a few LEDs if not spread out to limit current.


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## MrAl (Jul 7, 2005)

Hi Russ,

My cells are going down because of their storage capacity
just isnt there. The internal resistance really isnt that
bad i think, as the cell dies it stays low even after removing
load.

Yes i guess it's not easy fitting those LEDs into a small
package like that. How about a luxeon?

Yeah you could use two leds if you want with the comparator,
it's up to you. If you need a circuit just let me know.
Also, if you want a circuit for the timer thing let me know,
and it shouldnt cost much either because of the low parts
count. I dont know under a dollar, maybe under 2 ?


Take care,
Al


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## Lynx_Arc (Jul 7, 2005)

I would say use your cells for a low power LED light and get some better ones or a 6v SLA for your fluoro. I hope to have access to some SLAs around late august/september. 

I thought about making some boosted led PR bulbs but finding a good source of tiny parts for cheap doesn't look easy enough and making a pill for it looks labor intensive. As for luxeons they would be nice but require more heat sinking and few lights using PR bulbs have any heatsinking ability built into the holding sockets to suffice I would say. I am more interested in light non metal flashlights than metal ones, in cold/hot weather they don't burn for freeze your hand if outside or in the car all day accidentally in the sun. 

I may look into the timer bit. I have about 5-6 of the timer taplights and the stupid circuit drain makes them IMO useless as they can kill a set of batteries in a week or so without putting out any light at all. Those idiots at GE should have known that when they put their label on them. Luckily I paid 50 cents for most of them and they are cosmetically nice lights. I may just mod them all with regular switches. I saw some SPDT switches for about $2-3 dollars that can switch between two sources and/or combine them on. It gave me multiple ideas as I have just modded a cell phone booster I yanked the DC/DC inverter out of for 3 LED resistored drive (3AAA). It has a 3 position slide switch which has ON(high) ON(low) and OFF. the high is 70-100 ma depending on battery type, the low is 20-30ma and it has a momentary pushbutton high also. What makes it interesting is the orange clear shroud over the top that makes the LEDs look like an incan light filtering the blues/purples etc out. I got the SP3T switches for 30 cents and can get dozens of them.

Maybe you should be adventurous and send those to silverfox for his nimh shootout... that would give RS cells a black eye for sure. I saw some 2300mah energizers at a remote BigLots here for about 3.67/pair. (3.38+tax).

I may have to design a circuit for my next lantern because I want it to do a lot of things and without a DP4T switch I don't think I can begin to get things to all work. I plan to have two CCFL tubes and LEDs and maybe colored LEDs for razzle dazzle. I would like the LEDs to have several (at least 2) settings for high/nightlight use. I also want to put a findme mode (blinking red low power LED). so that may take 6 positions. I may be able to get a switch to do all that but it would cost about $15 and take up a bit of space.


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## MrAl (Jul 8, 2005)

Hi Russ,

Yes im looking forward to getting a 6v SLA at some point. I think it
will work much better.

Oh yes that's right...the Luxeons require some heatsinking for high 
output, but i've used mine at lower outputs without any HS's.
For example, the 1 watter doesnt seem to need any HS at 75ma or so.
There's less light output of course but it doesnt take up much room
and doesnt get hot.

It wouldnt take me long to draw up a timer circuit, but if you'd
rather design your own that's cool too.

Wow, SP3T swithes are my favorites! What size are they in inches approx?

Yes that's an idea (sending cells to Silverfox).

DP4T what do you need that for? I mean, why so may T's ? Oh so you can
have different LEDs and Fluor's connect in?
They make 10T switches but they are rotory, probably not what you want?
They do take up some room, maybe 1.5 inch x 1 inch?

Take care,
Al


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## Lynx_Arc (Jul 8, 2005)

I have 5 6v SLAs, one in a spotlight, a spring top lantern battery and 3 headlamps with SLA beltpacks. 

I think the biggest drawback of luxeons is for lower current lights they cost a lot compared to a handful of 5mm LEDs.

I may figure out how to use the current circuit and replace the transistor with a mosfet one, hopefully it will reduce the standby current

The SP3T switches are fairly small but they seem to be a little stiff from the start. Maybe I can mess with them and make them slide easier, but at 30 cents each they are a bargain. These are 5/8 inch long by 3/16 wide.

I want to be able to turn one or two fluoro tubes on/off for a two stage fluoro light plus a few LED settings. The optimum would be somewhere around 6throw or so but I find most rotary switches able to do that cost a fortune and are bigger than a half dollar in diameter. My projects are mostly done on the cheap since most hosts I am using are one time *bargain* buys and I am unable to get more for cheap.


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## MrAl (Jul 9, 2005)

Hi Russ,

Yes, the lower output with lower current seems like a
waste too, but i've done it /ubbthreads/images/graemlins/smile.gif

The circuit you have has a 555 timer chip in it right (?)
so that draws some current all the time. Perhaps 
replace it with a CMOS type 555 timer.

Yeah the 3T switches still sound nice...maybe slide them
back and forth 10 to 100 times might help?
Did you get them on the web somewhere or at a store?

It's also possible to construct a rotory switch using pc
board material etched with the pattern you want. I made
a 40 position switch once like that. Not that easy to do
though.


Take care,
Al


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## Lynx_Arc (Jul 9, 2005)

If Luxeons ever get down to $1 each they will probably start taking over the world and maybe even start replacing 5mm LEDs almost entirely.

I will have to figure out the wiring of the circuit but that seems like a possibility the timer is on all the time, Somehow I don't think it is overly simple to just replace the timer with a cmos version, may have to replace every part including the one transistor and all the resistors and the capacitor which means possibly just designing a whole new circuit unless the component count is nearly the same.

I got the switches at a local electronics supply. They have old stock out on the floor that some parts are prices cheap while others are outrageous. I think they figure when it all sells out they will reprice it when they replace the stock. I have found some bargains and seen some stuff I liked but not cheap.... like ancient nicads for expensive prices and almost no nimh stuff. 

I am still working on ideas for a switch in my mind for multifunction. I will either have to use several switches, a rotary switch or an electronic switch of some sort to control stuff. I also have to decide about the multiple battery source idea. I even thought about external power for the lantern using optional SLA of sorts perhaps 6 and 12v.
My initial idea was a 4-5 cell platform but now I am considering 4-5 alkaline or nimh and from 4.8-9v operating range. I may accomplish this using a regulator or just underdrive and overdrive stuff some and resistor seperate inputs for 4 to 6 cell inputs and sla. I like the idea of making a small jump pack either 12v or 6v for powering stuff. SLAs are so much easier to mess with due to their robustness compared to nicad/nimh. 

If they could only design a SNM cell that is robust (sealed nimh) it would be nice. Popping batteries in/out to recharged one a week isn't too bad but if you did that once a day it gets tiring and chances of damaging/destroying battery hatches increases.

It amazes me my portable stereo draws between 50-120ma in normal operating range (I don't run it very loud) but it has a 6D cell battery holder. I like the format of the ancient stereo as it is upright and square and all the new ones are short and lumpy/round. When you have limited counter/table space the newer stuff doesn't fit well.


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## MrAl (Jul 11, 2005)

Hi Russ,


Oh wow, Luxeons for a dollar each...cant wait /ubbthreads/images/graemlins/smile.gif
Yeah you're right, the price has a say in our projects too.

If you would like help with the circuit it's no prob for me.
Like i was saying, a resistor or two and a cap and MOSFET
should do it.

I didnt want to keep recharging my NiMH's in my fluor light
for the same reasons...it's a pain and risk damage.
The end cap is kinda fragile on this thing too :-(

Im waiting to see the newer batteries i've read about.
The alkies are supposedly twice as good as current, but
i wonder how long it's going to take to get them here
in the US...

Oh yeah, he he, some of the new designs in stereo boxes
are really strange, he he. Geeze, are these things going
to have to fly or play music he he. Did i mention 'he he',
he he. Sorry, even if they sound good i can only laugh at 
some of them /ubbthreads/images/graemlins/smile.gif


Take care,
Al


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## Lynx_Arc (Jul 11, 2005)

I will get back to the timer for the taplight one day, I am working on an 8LED taplight with various settings including a 0.5-1.0ma super low setting just bright enough to see it in the dark. I figure it should run for at least a month at that rate on some of my generic nimh cells. I figure the mosfet timer circuit will probably cost a little and think I will save it for a lantern or something more neato and robust. 

The stereos boom boxes today certainly are not designed for efficient use of table space, but I guess the CD players having to be upright causes that. After thinking about it I may get a hard drive MP3 player to hook up my stereo and adapt it to it as I hate carrying around a bunch of CDs.
I tried looking around at some hard drive MP3 player *kits* to make your own and the cost is too prohibitive for the electronics to do such well. Most circuits cost in excess of $100 and require use of a laptop drive and function doesn't seem to be an improvement of such.

Next thing.... Thor with MP3 player.... hee hee, an SLA powered player.


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## MrAl (Jul 13, 2005)

Hi Russ,

I did a test one time with a super bright green LED, 
driven at low current like that, and running of a simple
9v alkie cell. It ran for over a month and the battery
wasnt even new when i started the run.

The Thor...thats the one sold at Costcos right?
Is that light any good and what kind of SLA is it in there?


Take care,
Al


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## Lynx_Arc (Jul 13, 2005)

At a low enough current you can run an LED a LOOOONG time off just about any battery source. I figure 1200mah nimh running LEDs at a combined 1ma should last about 1200-1500 hours or about 50-60 days more or less not accounting for self discharge or voltage dropping causing the LEDs to run at even lower currents. I stumbled across a 4C 5watt lantern at BigLots for $7 that intriques me a little... could be a nice host for LEDs but most of my hosts have cost $1-3.

I don't know hardly anything about the Thor other than it must have a 12v SLA of some sort probably 10Ahr or more and it rather bright in a small tight spot.


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