Al_Havemann
Enlightened
I finally managed to get a dual battery tube made for an Fenix L0D CE and it was worth the effort even if it's not really usable except as an experiment.
The tube was a ***** to make, I use some thin wall tubing with a soldered bottom cap. The threads were (badly) cut by a friend at a machine shop, it's pretty messy, the threads aren't quite right and it looks like crap but it works (mostly).
Unfortunately, I don't have the skills or equipment to do a decent job but the head screws on well enough to test with and in my opinion the results are great. Keep in mind that I don't own any test equipment so everything here is just an eyeball measurement.
Alkaline NIMH or Lithium batteries all deliver pretty much the same output as far as I can see but on turbo using Lithiums the head heats up about the same as it does when I use a single 10440. The head barley warms up at all on turbo with Alkalines or NIMH.
So, it would appear that the L0D head is operating well within it's design parameters and is at its best efficiency when running from 2.4 to 3.0 volts. Increase the voltage much beyond that and it looks like efficiency begins to drop off and more power is lost to heat. As far as I can see, the output is essentially the same from 2.4 volts for a pair of NIMH cells all the way up to 3.75 for Lithium with the only difference being how warm the head gets. I suppose it's possible there's more output at the top voltage but it's not very obvious.
Although I haven't performed any formal run-time test, here's some info that may be of some use.
Batteries: 2 Lithium
Start Voltage: 3.72
Mode: High
Usage: Intermittent
Total logged: 151 Minutes
Result: No loss of output over the combined total time
End Voltage: 3.02
Comment: The head was pretty hot much of the time, so I suspect efficiency loss (heat) will nibble away some of the Lithium capacity advantage.
Batteries: 2 NIMH, PowerEX 2300
Start voltage: 2.67
Mode: High
Usage: Intermittent
Total logged: 114 Minutes
Result: Noticeable loss of output at 78 miin.
End voltage: 2.02
Comment: Although dimming is noticeable the light still has ample output on all levels. Solid performance considering that these PowerEX 2300 cells are over 2 years old and rarely cycled.
Batteries: 2 Alkaline
Start Voltage: 3.10
Mode: High
Usage: Intermittent
Total logged: 129 Minutes
Result: No loss of output over the combined total time
End Voltage: 2.63
Comment: It was unexpected, but Alkalines performed just fine here. Perhaps with two cells in the supply to share the load, the usual problem of rising internal resistance at high current levels is reduced?. At any rate, there seems little reason to bother with the self discharge of NIMH or the high cost of Lithiums when cheap Alkalines perform so well.
(This one was just for fun!)
Batteries: "Dollar Store", "Heavy Duty", ? batteries ? (they gurgle when shaken)
Start Voltage: 3.16
Mode: High
Usage: Intermittent
Total logged: 82 Minutes
Result: Very noticeable loss of output by 47 minutes
End Voltage: 2.1
Comment: These batteries maintained high output for just under 50 minutes before the light dropped out of high mode to low. It was maintaining that level when I got tired and dumped the batteries on the trash (where they belonged).
I'm very impressed by the performance of the L0D CE with 2 cheap Alkaline batteries. Here I have a tiny, potent light with output that competes with the best, it fits in any pocket, runs for hours on most any battery combination.
Wish List for a 2 AAA version of the L0D CE with some changes:-
1. Get rid of the strobe and blink modes, these just get in the way
2. Change the mode sequence from "Medium, Low, High" to "Low, Medium High"
3. Double or triple the PWN rate **
4. A good, long pocket clip on the tail
I would really like to see the Strobe and Blink modes disappear. Frankly, I can't see any possible use for either of them and they just get in the way. To much twisting, every time I go to <twist, twist> high for a quick look I have to <twist,twist,twist> to get back to low.
I know it's not likely to happen but if they made it, I'd like the new tube to have a couple of tiny rubber dome buttons or something similar on the flat section of the tube to step the brightness up/down. The buttons would just signal for a mode change not control power, twist on/off does that. I don't know if that's a reasonable wish or not but it seems to me that if a twist can change modes, than it should be easy to add a couple of buttons.
Last, I'd really like to see a doubling or tripling of the PWN rate, it's a problem for service people like me because every time I open a computer or most any device with a fan, the lights PWN makes the fan look like it's running slow, and it's really almost impossible to tell for sure if it is or not. A dying fan or a healthy one can look the same under PWM, so I have to switch to turbo <twist><twist> (no PWN,) then switch back to low (<twist,twist,twist>). Annoying indeed!.
So there you have it; give an L0D CE a dual battery tube, make a couple of minor programming changes and you've got a a tiny shirt pocket light, incredibly powerful when you need it to be, politely dim when you don't and hours of run time on the cheapest of batteries.
It's enough to embarrass a top of the line Surefire.
Al
The tube was a ***** to make, I use some thin wall tubing with a soldered bottom cap. The threads were (badly) cut by a friend at a machine shop, it's pretty messy, the threads aren't quite right and it looks like crap but it works (mostly).
Unfortunately, I don't have the skills or equipment to do a decent job but the head screws on well enough to test with and in my opinion the results are great. Keep in mind that I don't own any test equipment so everything here is just an eyeball measurement.
Alkaline NIMH or Lithium batteries all deliver pretty much the same output as far as I can see but on turbo using Lithiums the head heats up about the same as it does when I use a single 10440. The head barley warms up at all on turbo with Alkalines or NIMH.
So, it would appear that the L0D head is operating well within it's design parameters and is at its best efficiency when running from 2.4 to 3.0 volts. Increase the voltage much beyond that and it looks like efficiency begins to drop off and more power is lost to heat. As far as I can see, the output is essentially the same from 2.4 volts for a pair of NIMH cells all the way up to 3.75 for Lithium with the only difference being how warm the head gets. I suppose it's possible there's more output at the top voltage but it's not very obvious.
Although I haven't performed any formal run-time test, here's some info that may be of some use.
Batteries: 2 Lithium
Start Voltage: 3.72
Mode: High
Usage: Intermittent
Total logged: 151 Minutes
Result: No loss of output over the combined total time
End Voltage: 3.02
Comment: The head was pretty hot much of the time, so I suspect efficiency loss (heat) will nibble away some of the Lithium capacity advantage.
Batteries: 2 NIMH, PowerEX 2300
Start voltage: 2.67
Mode: High
Usage: Intermittent
Total logged: 114 Minutes
Result: Noticeable loss of output at 78 miin.
End voltage: 2.02
Comment: Although dimming is noticeable the light still has ample output on all levels. Solid performance considering that these PowerEX 2300 cells are over 2 years old and rarely cycled.
Batteries: 2 Alkaline
Start Voltage: 3.10
Mode: High
Usage: Intermittent
Total logged: 129 Minutes
Result: No loss of output over the combined total time
End Voltage: 2.63
Comment: It was unexpected, but Alkalines performed just fine here. Perhaps with two cells in the supply to share the load, the usual problem of rising internal resistance at high current levels is reduced?. At any rate, there seems little reason to bother with the self discharge of NIMH or the high cost of Lithiums when cheap Alkalines perform so well.
(This one was just for fun!)
Batteries: "Dollar Store", "Heavy Duty", ? batteries ? (they gurgle when shaken)
Start Voltage: 3.16
Mode: High
Usage: Intermittent
Total logged: 82 Minutes
Result: Very noticeable loss of output by 47 minutes
End Voltage: 2.1
Comment: These batteries maintained high output for just under 50 minutes before the light dropped out of high mode to low. It was maintaining that level when I got tired and dumped the batteries on the trash (where they belonged).
I'm very impressed by the performance of the L0D CE with 2 cheap Alkaline batteries. Here I have a tiny, potent light with output that competes with the best, it fits in any pocket, runs for hours on most any battery combination.
Wish List for a 2 AAA version of the L0D CE with some changes:-
1. Get rid of the strobe and blink modes, these just get in the way
2. Change the mode sequence from "Medium, Low, High" to "Low, Medium High"
3. Double or triple the PWN rate **
4. A good, long pocket clip on the tail
I would really like to see the Strobe and Blink modes disappear. Frankly, I can't see any possible use for either of them and they just get in the way. To much twisting, every time I go to <twist, twist> high for a quick look I have to <twist,twist,twist> to get back to low.
I know it's not likely to happen but if they made it, I'd like the new tube to have a couple of tiny rubber dome buttons or something similar on the flat section of the tube to step the brightness up/down. The buttons would just signal for a mode change not control power, twist on/off does that. I don't know if that's a reasonable wish or not but it seems to me that if a twist can change modes, than it should be easy to add a couple of buttons.
Last, I'd really like to see a doubling or tripling of the PWN rate, it's a problem for service people like me because every time I open a computer or most any device with a fan, the lights PWN makes the fan look like it's running slow, and it's really almost impossible to tell for sure if it is or not. A dying fan or a healthy one can look the same under PWM, so I have to switch to turbo <twist><twist> (no PWN,) then switch back to low (<twist,twist,twist>). Annoying indeed!.
So there you have it; give an L0D CE a dual battery tube, make a couple of minor programming changes and you've got a a tiny shirt pocket light, incredibly powerful when you need it to be, politely dim when you don't and hours of run time on the cheapest of batteries.
It's enough to embarrass a top of the line Surefire.
Al
