SF A2 and Cr123R's

Bullzeyebill

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SF A2 and Cr123R\'s

Will two Cr123R's, that peak out at 4.2 volts each, work in the A2?

Bill
 

Krit

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Re: SF A2 and Cr123R\'s

The SF said 2*R123a will work to the circuit of incandescent bulb but we have to change R for LED because it is direct drive.
 

Size15's

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Re: SF A2 and Cr123R\'s

No, the LEDs are 'protected' from the full force of the batteries by resistors. If you change the type of batteries powering the A2 you will need to change the resistors protecting the LEDs otherwise they will be damaged.

This is not an easy task.
 

Krit

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Re: SF A2 and Cr123R\'s

Yes, led were direct drive from battery which drop by resistor. So you have to increase value of resistor to protech over drive too much current to LED.
 

carrot

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revolvergeek said:
What about running it on a single protected 17670?
It's not enough voltage to make the regulator power the lamp. This is intentional, or so I was told, to ensure that (on primaries) you have plenty of low-output burn time.
 

leukos

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Bullzeyebill

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revolvergeek, where did you find this thread? LOL. Can't believe I wondered if "R" meant red! I now have an A2, and yes it can run with two RCR123's, as leukos says. I have red leds, and each resistor is marked "100" or is it "1000"? greenLED has it right now, for testing different A2 led colors.

Bill
 

revolvergeek

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I just used the google search box for "surefire a2 rechargeable" and up it popped. :D

I have plenty of rcr123s laying around, so if those work I may have to give that a try if I work up the courage. I picked up a fairly new A2 (w/ red leds) last night from a friend of mine and I have to admit that I like it a lot more than the previous one that I had (back when they first came out). It seems somewhat shorter and sleeker than the other one.

Danny
 

Bullzeyebill

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revolvergeek, I think I have one of the older A2's with four flat sides. Also have red leds in it. I think the red leds have high resistor values. Values are noted in my previous post. What are the values of your led resistors. Careful, don't drop incan LA, easy to do. Oh, yeah, you may not want to unscrew the led ring to check.

Bill
 
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