Re: FS: hi/low spring assembly for ARC LS (NEW)
Daniel,
I'm not sure what output I _meant_ to calculate, but you're right, what I _did_ calculate was 0.05W. Sigh. You missed that I also did 6V minus 3-3.5V = 1.5-2V -- should have been 2.5-3V! Did I mention I'm a mathematician, professionally?
Right then: Approximate the diode drop as constant, say 3V (low is pessimistic here), so current through the resistor equals current through the diode and is proportional to the LED output power. Voltage drop across the resistor is constant: battery - diode = (6-3)V. Power across the resistor is thus (6-3)/3 times the output power -- equal, with these values. Want 0.1W output? Waste 0.1W across the resistor. No problem for a 1/8 watt resistor, and still a lot less net power than at full throttle. (And the Pelican's use of 6V direct drive for a little 3V-drop 1W Luxeon is an unusually bad case.) The resistance needed for output power X is 3(6-3)/X; for X=0.1W it's 90ohms, very different from the 10ohms the Arc wants.
Having plunged off the deep end, with both the Pelican and now also one of those newly discounted Arc LSH's on the way, I'm expecting to want one clickie adapter for the Pelican (100ohm?) and one for the Arc (10ohm). I'll wait for the flashlights to come, to make sure I like them, to see if the Pelican's tailswitch is physically similar to the Arc's, and to try out a couple of resistor values on the Pelican, but then I'll be ordering from you!
After perusing the related threads, I'm right in thinking that the clickie-switch units you're selling are a bit tricky to get right, but that a twistie-switch adapter is a simple enough DIY job? (Assuming I like the Arc, I'm hoping to get an Arc twistie soon.)
I'm glad you're continuing to make the spring adapters.
Thanks,
Greg