Uniquefire AA-S1 + NGJ-18

The Uniquefire AA-S1 is a very nice single mode AA light. If you decide you want to convert it into a multimode light you quickly find that it's hard to find an appropriate driver that will fit into the 14.7 mm space.

Fortunately miguelmoreto has already descibed [1] how to easily squeeze a 17 mm board into a Trustfire F20 by removing a brass ring used for making the ground connection. His instrucions work almost perfectly.

The brass ring was pressed in too tightly to be pried out so instead I used a small dremel tool to cut the ring, after which it slid out easily. I am keeping the ring in the event I ever want to revert to the old board.

I chose the NJG-18 for two reasons. First, one of its programmed groups has mode of low-med-high with no disco modes. Second, the output voltage is adjustable. That I thought might be an important feature, in that the Vf of the Osram emitter is 2.4 V and most drivers seem to be designed for the higher Vf of Cree emitters.

The battery current for different settings of the adjustment potentiometer follow.

With the pot set at 1/8 turn ccw (-1 on the graph) the output at 1.00 m is 77 lx, 420 lx and 810 lx. The maximum output is slightly lower compared to what I measured with the original driver, ~950 lx.

Note that with the pot set to 2/8 ccw (-2 on the graph) it refuses to go into high mode.

All in all I'm even happier with the AA-S1 than before. I normally use low mode around the house, which should result in about 18 h battery life. The high mode is just as bright to my eye as before.

All those nasty blink modes are still a trap for the unwary. The 12f629 is asking to be reprogrammed next.

[1] http://sites.google.com/site/miguelmoreto/home-eng/projects

Cheers,
Angus

Nice mod, Angus. I haven't had a chance to play with that particular driver yet, only read about it. Looks like DX is out of stock on them, but a place here stateside has them (e-lectronics.net). Looks like you can adjust the pot for a really low low.

Again, nice mod!

Thanks for your comments, Match.

I'm looking forward to hearing about your experiences with the NJG-18 in the future. It promises to be an ideal universal board for driving most anything.

In the meantime I'm still puzzled why mine can't get above 1.3 A input on a single AA. More than likely just a dodgy ground connection to the body. On the DX forum they're reporting over 1 A to the emitter.

I'll post new results if anything changes after I clean up the connection.

Cheers,
Angus

After re-doing the ground connection, the battery current is now 1.88 A at 2/8 ccw on the pot.

Lux at 1.00 m: low 109, medium 420, high 1248

Or in terms of throw: low 10 m, medium 20 m, high 35 m (using the square root rule)

This is the new graph.
At 3 eighths of a turn ccw the high current remains at 1.7 A, the same as medium.

For the next day or 2 I'll leave it set at -2 before reverting back to -1 or maybe even 0 for better battery life.

Cheers
Angus