NLD MD2/3 with some measurements

[Buck91]

Recently received my MD2 M61N H/L along with an extra MD3 body and had to check some numbers out. Pretty happy with this setup (not that I'm suprised as I have a number of malkoff drop ins in various SFs already). I also toyed around with my 2nd run M91BN just to see, although I really need to replace those old AW 17500's. Measured voltage from B- to the body threads so it should be somewhat close to operating voltage.

M61N readings:
3xCR123 8.46v
H 0.774A
L 0.080A
2xCR123 5.65v
H 0.9A
L 0.043A
1x18650 3.653v (after full charge to 4.20v on the cell)
H 0.973A
L 0.019A
2xAA NiMH with a fresh charge
H 0.073A
L 0.001A

M91BN
2x17500 AW cells, 6.95v 1.53A
2xAA NiMH 2.395v 0.3A


Interesting that the M61N is definitely "usable" on 2xAA if only as a last ditch back up, though I don't know for how long. It did perform much more impressively off some partly used L91's but I didn't have the DMM out at that time. Echoing others results the M91BN seems to run quite happily off 2xAA! Drawing 0.3A off a pair of NiMH LSD cells, this should be a quite functional backup or alternative powersource in a 3xCR123 body. Pretty cool! Also interesting is how efficient the M61N appears to be off a 1S cell. 0.973 amps off an 18650 cell should result in somewhere around 3.5hrs of runtime on high which is pretty nice. Even nicer is you are looking at 180+ hours on low with the same cell and with plenty of output for most typical tasks. I wish I would have grabbed low output amps from the M91BN not sure why I didn't...

Trying to decide if I want to replace those old AW cells with 17500 to work in my C3 and 9P bodies or just go to 18500 for some extra capacity in the MD3 body....

 

[ekardscribner73]

Your M61N measurements are almost exactly what I measured using those battery combinations.

 

[ekardscribner73]

I have the KeepPower P1850C3 2300mAh batteries and they are the bees knees. I like the Surefire three-cell bodies but it seems you can't beat the MD3 for anything serious. And you have the option of one day putting a T-series head on it if you wish.

 

[etc]

M61 on 2xAA is the ultimate battery vampire, I estimated that the lumens off alkalines are about 1-2 lumens. A bit more with L91s and NiMH.

I wonder what the runtime is of M61 off 2xAA alkalines.

Definitely a most useful combination when you want something close to moonlight mode.

But not so dim as to be unusable (I can't use 0.2 lumens for example).

 

[thermal guy]

85 hours. Just found my test. With a M61N😁