Resistor value in McE2S for use in TW4

Can I get some feedback on which of Don McLeish's four resistor values (15, 22, 30, 60) used in his McE2S tailcap switch, would be best for the low level of my TW4 light? Consider that I would like to have an output of approximately 2 or 3 lumens, similar to the low level of my L1. This level is very useful, efficient, cost effective, and cool running.

My McE2S switch presently has a 60 ohm resistor in it. I am using it in my L4. It gives me the ultra low output I desire. My imagination is running wild, and I would like the switch to be useful in my TW4. When I tried the switch, the four dies energized, but that was it. No light output whatsoever. I was thinking that the 22 ohm resistor would be a good starting point.

I don't have an L1 but I just tried a 15 ohm in my TW4 and it is quite dim in my opinion. I tried my 10 ohm and i think the low level it puts out is more useful. I would suggest starting at 15 ohms. YMMV.

Herman

Just tried the 22 and 15 ohm tail caps on the TW4. Compared the beams to my old L1. Looks like you might want the 15 ohm tail cap. At least that is the one I would chose.
oldgrandpajack

Thank you "Chooch", and "grandpa." Judging by the number of viewers (94) and the number of respondents (2), my question doesn't have a definitive answer. But you have lead me on the right path. Until now, it never occured to me that 60 ohms would be too high in a one cell light (TW4), when it only puts out about 2 lumens in a two cell light (L4).

I think that I will have to take a variable resistor and my digital ohmmeter, and place it in series with the TW4 battery negative and the battery tube. I will be able to adjust the resistance on the fly. When I get the light output that looks good, I will look at the ohmmeter, see the value, and call it a day. I hope that this value will be close to 15 ohms or 22 ohms, since Don has only fabricated his pc boards with these values, beside the 30 and 60 ones. Stay tuned!

60 ohms with 1x123 and my L4 head produces similar results to what luxlover saw if I have a brand new 123 cell, but after the cell has been used a bit, it apparently drops below the threshold needed to activate the emitter.

It's actually the perfect setting for photographing the Luxeon-V:

[larger image]

It looks like the verdict is in........ The best of Don's resistors for me, shall be the 22 ohm one. It seems that as I had the light connected to the variable resistor, and was manually changing the resistance as I shined the TW4 in a dark room, the output I liked the most happened at about 22 ohms. At any lower resistance, even when I manually set it at 15 ohms, the light was brighter than I wanted. I am very relieved. I wonder if Don will sell me a 22 ohm pc board for my switch? If he won't, where else can I buy one to fit the McE2S?

I highly recommend using a good quality variable resistor, when experimenting with resistor values and hookups to a light's power supply are possible. Make sure that the power rating of the variable resistor is at least that of the light. This means when it is at minimum resistance, and the light is at maximum output.

Correction on my variable resistor setup....

In my second post in this thread, I stated that I had an ohmmeter in series with the variable resistor when the light was on. One cannot have an ohmmeter connected to a circuit while a power supply is engaged. I most certainly did not. Only the resistor was in series with the battery. When I was happy with the light output, I removed the resistor and measured it. End of story!