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1xAA Blu-Ray from Ebay

Snytbaggen said:
I see... :/ Sorry for asking so much, but what would the current be? And as a side question, is 100mA a safe current for a PHR-803T diode? I recently got in on the GB for them and is trying to find out as much as I can to prevent destroying anything :D
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I've been running mine for a couple weeks now @ 100ma w/o any problems, often several minutes at a time. ;)
 





roSSco said:
[quote author=Snytbaggen link=1210525544/24#31 date=1212167260]I see... :/ Sorry for asking so much, but what would the current be? And as a side question, is 100mA a safe current for a PHR-803T diode? I recently got in on the GB for them and is trying to find out as much as I can to prevent destroying anything  :D
Click to expand...
I've been running mine for a couple weeks now @ 100ma w/o any problems, often several minutes at a time.  ;)[/quote]

Yeah, that's what I thought, but I just wanted to make sure. Now the question remains: can the boost driver in the flashlight put out 100mA?

Man, it really feels like I'm asking a lot. Well, I do, but you get what I mean :P
 
Anyway, I've ordered one from DX and hopefully I'll soon be able to measure the current in these.
 
This should be awesome if you can run the driver at 100mA.
All you'd need would be
a 5 dollar host/driver
~20 bucks for a hd-dvd drive
maybe a >$1 resistor.

Keep us updated, and maybe somebody should start a new thread so we aren't threadjacking the OP's thread.
 
Sorry for reviving this two week old thread, but I recieved the flashlight in question here and have measured the voltage and current in it. Since there has been a fair amount of discussion around it I felt I should post the results here. First, just one important thing:

THIS ONE DOES NOT HAVE A BOOST CIRCUIT!!!

At least, mine don't. As I can tell with my little knowledge about electronical components the driver consists of two caps, two surface mounted transistors and one surface mounted resistor. When measured at the LED seen at right in the picture the output was ~1V with a 1.2V NiMH battery. I didn't bother to check the current, since it seemed pretty pointless to do so.

I guess I'll just have to buy a lavadrive for this and a 3.6V AA-sized lithium.
 

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No, the other "cap", the black one, is a inductor. Or at least looks like one.
 
*Just a theory*

Ok, I'm not an expert when it comes to electric stuff. But I think there some room for improvement.

Fist of I can't believe that the LED even can light up with only one volt, so the problem might in the voltmeter.

Maybe if you connect a 1n4001-diode in series with the LED, and put a, IKD, maybe a 47µf 10-50v capacitor in parallel with the LED and try again with the driver.
It might work. :o


But in the end, the lavadrive is the best indeed.
 
I measured with two different voltmeters and got the same results both of the times :P But I agree, it does sound fishy. I measured by the ends of the red cables at the diode. Can someone confirm this is the right way to measure, since I've started to doubt the results?
 
the LED may be running pulsed so the meter is only reading a kind of average - try connecting a capacitor as FML recommended
 
A white led will not light from 1 or even 2 volts indeed. Most require at least 3 to light at all and between 3.5 and 4 for normal operation.

It's likely that this is just an ill designed driver, operating the LED on AC. This will usually work since leds can tolerate a fair amount of reverse voltage.

You can rectify the output as suggested using a diode and capacitor, and take your measurement again. The 1n400x is a poor choice though, since these boost circuits often run in the 100 kHz and up frequency range, and the 400x series are very slow. I'd suggest a shottkey diode, and if you must use only 'standard' components, a few 1n4148 in paralel (1 for each 100 mA output).
 
Yeah, I might try that someday. The thing is that I don't have any electrical components at home, and the only person I know that has any is my grandpa (which has a pretty large selection of components). But I guess it's not safe to drive a bluray from one of these.
 
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