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ArcticMyst Security by Avery

Dorcy build glitches

Joined
Nov 22, 2008
Messages
1,506
Points
48
Hi, I recently built a Red dorcy using a long-open can diode at 420mA using a flexdrive. At first I wasn't sure of the power output, since it looked dimmer than last time, but I had bought a green pointer since and I initially blamed that for "skewing" my perspective of brightness. However, I recently noticed a thread, saying the spring makes direct contact with the battery. I checked and realised I had forgotten to remove the built-in driver from the Dorcy. My questions are as follows:

Would this board stop my laser having the same output power as it should? I thought the flexdrive would simply cut the output if it wasn't outputting the full current?
Will this have damaged any components of my build?
How do you go about removing it?

If I measure the current through the tail, it comes out to around 270mA, using a rechargable CR123 battery.

Thanks in advance for any help.
 





daguin

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Joined
Mar 29, 2008
Messages
15,989
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It will affect the performance of your laser.

Remove the batteries and head.

Use a pen or punch or anything long enough to reach the stock driver board with some of the rod still sticking out the tail end.

Push the driver and black plastic fitting out the front.

Replace the black plastic fitting

Re-assemble the head and battery compartment.

Peace,
dave
 
Joined
Nov 22, 2008
Messages
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Thanks for the quick response - I got the board out, but the current reading has only gone up to 287mA. The battery voltage is 3.92V so that's:
3.92v*0.287a=1.125w

Expected characteristic of diode:
2.7v*0.420a=1.134w

Is the diode receiving enough power now? According to my maths it isn't, but it's certainly close. What about the driver's own inefficiency? Is this within the tolerances of an ageing multimeter? Sorry if the question seems noobish but I'd just like to be sure I didn't accidentally break anything in the process.
 
Joined
Dec 26, 2007
Messages
682
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How are you measureing the current of the driver-setting?
If you are measuring battery-draw, it will be skewed due to the boosting of the Flex-drive. The current must be measured on the diode-side of the driver, using a 1ohm-resistor and a test-load, or diode. Never power-up the Flex-drive without a load of some kind, it will damage it.
 
Joined
Nov 22, 2008
Messages
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As I mentioned earlier, I measured the current battery-side, giving a reading through the tail-cap section. Why does the flex-drive affect current readings between battery and current side? I know it "pulses" voltage through the inductor, and therefore loses energy. Does the high frequency of the driver affect the reading? I think it probably is just that I got used to being dazzled by the green pointer, and now reds don't look so bright any more. It's still too bright to comfortably look at up close.

Either way, I'm very pleased with the build kit, and especially pleased with the uranium marbles (free due to pre-ordering!), but sadly no 405nm laser ATM - thanks Dark_Horse.
 




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