# Ideas wanted for "Consuming" Outdated LEDs



## bhvm (Jan 20, 2013)

Hello all!
I have many of Cheap and Outdated LEDs (In thousands) lying around. These were purchased long time ago (2003~2005) when luxeon Stars were hardly available and costed Rs 1000 a piece. These LEDs are-
5mm 20 deg White ~100pc
4.8mm "Straw Hat" Low dome 100 deg White.~ Many

1)Both of them are rated at 20ma, 3.2 volts.
2) Straw hats are twice as better (Life, brightness, Even-ness) than low beam angle 5mm ones
3)I learnt the hard way using these in many precious projects. Now I know very well that 5mm LEDs dim considerably even at 20ma after a year intermittent use. I had made 36-LED matrixes (about 2 watts) with good spacing between LEDs, Legs uncut still went dim after a year.
4)There is a huge variation in Tint, Voltage and output of these. Straw hats are better , but still
5)These are not entirely Cheap in money per-se. Costed 3 Rs per piece. Today a reasonable spec Chinese 350ma Star costs 40 a piece. If we consider a bunch of 18 of these to make that wattage, They add up to Rs 55 
6)Advices to throw them in the bin/ Donating/ smashing with bulldozers./ Overvoltage Fun etc are not my idea.
7)Don't want to spend tremendous time/energy/money than they're worth.


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## AnAppleSnail (Jan 20, 2013)

Is it worth your time to use them? You could:

Make emergency lanterns or decorations. Wire dozens in arrays that drive them at 10 mA, expecting 4.5-5v input. Connect these to USB-5v chargers or 3x(alkaline) cells as needed.

Make highlights for a room. Create a long string going around the upper trim of a room. Always-on at low current.


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## bhvm (Jan 20, 2013)

Thanks for dropping in, AnAppleSnail

I was thinking of these ideas, Wire many of them (overkill) and keep them to 10mA. I could then use them as Night time security lights, where tint and even brightness won't matter much.

Any ideas of power suply?

Keep other ideas Rainin'!


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## StarHalo (Jan 20, 2013)

Yeah, I came to the same conclusions. Check out Pak-lites for inspiration. As for decorations, good ol' Christmas lights or rope lights powered by mains..


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## bhvm (Jan 20, 2013)

StarHalo said:


> Yeah, I came to the same conclusions. Check out Pak-lites for inspiration. As for decorations, good ol' Christmas lights or rope lights powered by mains..


Pak lites! These are dime a dozen here locally; Actually Rs 30 a piece minus all the quality.

For string lights,
240v X RMS Divided by LED vf? Crude and dirty but may work!


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## Esko (Jan 20, 2013)

Home decoration was my initial thought, too. One could give some emphasis to bookshelf items, etc. The construction could be very simple, just solder the leds directly to a dual core wire (parallel) and attach a driver and power supply to the other end.

You could also put them in your clothes. For safety, utility, or party usage. A cap light, for example. A small low current driver could be hidden in a little fabric pocket and the battery could be attached with little magnets when light is needed.

Joule thief circuits could also be used to make some small emergency lights that could be put everywhere.


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## bose301s (Jan 20, 2013)

Put a bunch in the microwave and start it, be sure to film the results.  :devil:


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## argleargle (Jan 20, 2013)

BHVM, here's what you do!

First, go watch this... The 500-LED "Dominator" http://www.youtube.com/watch?v=NkkU0UO3sek

Since you have thousands of LEDs, make two Dominators (and send one to me)


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## StarHalo (Jan 20, 2013)

argleargle said:


> First, go watch this... The 500-LED "Dominator" http://www.youtube.com/watch?v=NkkU0UO3sek



Ugh, that's worse than the microwave idea..


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## bose301s (Jan 20, 2013)

StarHalo said:


> Ugh, that's worse than the microwave idea..


The microwave idea is an AWESOME idea, it's fun to put things in and see what they do, lol.


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## Illum (Jan 20, 2013)

Luxeon colored LEDs are not bad for what they are even in this day and age, especially the red and cyan flavors. CREE XR-Es retrofit nicely into LED nightlights. Most if not all LED nightlights employ 5mm LEDs powered by a capacitor fed full wave bridge. The high forward voltage of XR-Es makes them very tolerant in CV applications. The Feit Electric ones I have all over the house puts out about 3.5V at 15mA [tested using an XP-G]. In addition, a 20mm or even a 10mm star in itself is sufficient heatsink for the LED at that current level. When I am at friends houses and see their nightlights with near dead 5mms, I would offer to do lamp swaps on them with "obsolete" CREE XR-Es and XR-Cs, often with spectacular results: [3-4 times the output]. With this method I consumed about a dozen XR-Es before I moved on to XP-Es.

As for 5mm LEDs, I haven't found a use for them. Even at 15mA they have a tendency to degrade in intensity under continuous use within a year. I'd say buy cr2016s in bulk, buy stamp ziplocs in bulk, buy magnets in bulk, then make LED throwies. Pak-lites don't use complicated circuitry, just a simple 9V snap connector and a couple resistors, yet they are very popular.



> 7)Don't want to spend tremendous time/energy/money than they're worth.


:lolsign:
As a hobbyist, I'd say that statement is invalid. To attain the objective of having fun and being productive while doing it, more often than not the act of salvaging a component from a junked appliance and root it in a circuit drawn from scratch alone is spending more time and energy than the components worth. What I could make can be bought from stores, but wheres the fun in that?


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## StarHalo (Jan 20, 2013)

Illum said:


> make LED throwies



Was going to suggest this also, but no one's ever found a productive use for throwies either, so the Pak-/survival-light idea still tops the list (and CPFers like buying survival lights, throwies not so much..)


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## argleargle (Jan 20, 2013)

StarHalo said:


> Ugh, that's worse than the microwave idea..





bose301s said:


> The microwave idea is an AWESOME idea, it's fun to put things in and see what they do, lol.



 I used to hook unwanted 5mm leds to wall current. With all these new wicked emitters, you might want to wear sunglasses, face protection *and do that outside*. When you hook a 5mm direct drive to a 12 volt car battery, you might get a neat sparkler effect for up to 3 seconds. Wall current is more like a flashbulb.

I wonder what the cool failure mode of the current crop would be? It's easy to blow one up, but not so easy to find the COOLEST way to blow one up!

...and Ilum, your posts are awesome as always! 110%, what that guy said!


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## SemiMan (Jan 22, 2013)

Anything I can think of I can probably do with far far less effort using strip lights which are dirt cheap these days.

I would just give them to a local high school electronics shop. Performance does not matter when you are learning.

Semiman


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## argleargle (Jan 22, 2013)

+1 to what Semiman said. You might even get a charitable donation receipt for your taxes.


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## bhvm (Jan 23, 2013)

SemiMan said:


> Anything I can think of I can probably do with far far less effort using strip lights which are dirt cheap these days.
> 
> I would just give them to a local high school electronics shop. Performance does not matter when you are learning.
> 
> Semiman


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## StarHalo (Jan 23, 2013)

...star field ceiling..


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## bshanahan14rulz (Jan 23, 2013)

StarHalo said:


> ...star field ceiling..



My vote's on this


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## argleargle (Jan 23, 2013)

StarHalo said:


> ...star field ceiling..



+2 on this, combined with several packs of those "glow in the dark" ceiling star stickers.


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## suprlite (Jan 24, 2013)

How about making a looong string of lights powered by a longlasting battery and hook this up to a helium-balloon. Send it up in the air on a dark night.
Who knows? It might result in a number of UFO sightings


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## uk_caver (Jan 24, 2013)

suprlite said:


> Who knows? It might result in a number of UFO sightings


That kind of thing certainly can do.
A friend of mine told me of a time (a long time ago) when he and some friends let off a home made hot air balloon made from garbage bags with an alcohol-based burner underneath.
It got to a decent height and distance away before the bags caught fire and it plummeted to earth.
That resulted in various UFO sightings, and at least one report to emergency services of 'a microlight crashing in flames'.

Talking to a fireman friend years later, it seems that it was by no means a one-off kind of event.


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## argleargle (Jan 24, 2013)

UFO sightings, eh?

Heh! UKC, you're describing a home made "fire kite." You can buy large packs of factory-made for cheap. The really cool ones are made with flash paper.

How about one carrying a multicolor strobe beacon?


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## bshanahan14rulz (Jan 24, 2013)

Reminds me of the solar bag kite. It's a giant, light-weight cylinder of super thin black trashbag material. You tie off one end, fill it with air, tie off the other end, and put a strng on it, and the air will eventually warm up enough to start it floating. Always wondered how high one of these could go.

Imagine if you made a balloon, put a 9V powered LED light in/on it. Whoever finds it gets a nice, 9V user-upper for the price of throwing away a balloon!


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## Illum (Jan 24, 2013)

bshanahan14rulz said:


> Imagine if you made a balloon, put a 9V powered LED light in/on it. Whoever finds it gets a nice, 9V user-upper for the price of throwing away a balloon!



I've done that before back in high school using 9V battery + Luxeon LED set in flashmode..... Buy a dozen balloons, make a dozen modules. Drive up and release them on a windy day across campus towards the stadium during one of those football nights. The next morning you'll hear all about it during class. People come up with weird speculations about the flight pattern, and its well worth the cost to keep them guessing. Whats the driver you say? salvage a string of flashing incandescent xmas lights. In the old days the lamps uses a bimetal strip which disconnects the filament when hot and connects when cold. All one had to do was wire the LED in series... cold tungsten served well as a current limiter.


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## n2stuff (Jan 26, 2013)

Or you can try this.............
http://www.instructables.com/id/Haphazard-a-playful-random-light-system/


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## fyrstormer (Jan 26, 2013)

If they're going to wear out in a year anyway, save your effort to use with newer, better LEDs, and throw the old LEDs away.


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## bhvm (Jan 27, 2013)

Thanks for all the replies, 
You'll see these in coming instructables Shortly, 
Thanks.


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## Hooked on Fenix (Feb 5, 2013)

You can try this:
www.youtube.com/watch?v=2LBUM6iqEno (using a hotdog as a resistor for l.e.d.s using 120 volts)

This is what I would call dinner and a show.


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## Illum (Feb 5, 2013)

:lolsign:
We had a thread on this, http://www.candlepowerforums.com/vb/showthread.php?168675

Not really the best way to "consume" them per say... 5mm LEDs are not chewy and might even ruin dentures.


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## argleargle (Feb 6, 2013)

The hotdog resistor reminds me of using wet spaghetti noodles as conductors for RS-232 serial communication between two laptops. I recall getting over 96k/second!

Thanks for mentioning this stuff, guys! I'd missed the hotdog resistor.


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## Zapiao (Feb 25, 2013)

Those outdated leds are all working?


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## WeLight (Feb 28, 2013)

There are star board specific housings for indoor and outdoor lights, but will incur extra cost I guess


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