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Laser getting dimer?

Lasermodder

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For some reason, every time I turn on my power rock it seams to be dimmer than the last time, even if its right after I have just turned it on. It has gotten much dimmer from when I first got it. Also I have tested the battery, and that is not the problem. I charge it, then put it in the laser, then charge it and the next time no matter how long or short I wait, its gotten dimmer. :wtf: I could really use some help.
 



aryntha

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That doesn't neccessarily mean it's not the battery. However, are you saying it's instantly dimmer each time you turn it on? Or it starts bright and dims quickly?
 

Mattman420

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I've got the same issue with a green 50mw pen. Mine however is the latter of the two. When I power it on it dims so fast my girlfriend can't really see it but I can. Maybe a quarter of a second. It hasn't lost power from use but it has done that from the manufacturer. I wasn't to concered beach use it's a cheap laser and I still enjoy the kaleidoscope caps. Would like to k ow what causes that tho? Could it be the load on the battery? I'm using rechargeable triple a's
 

aryntha

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Well, after a while, rechargeable batteries can end up just holding a 'surface charge', meaning a charged area gathers near the anode and cathode but the rest of the cell is pretty much dead. The charger will still see it as charged, but it won't be.

When that happens, the phenomenon is, you get a short burst of nominal current, then it dies off. So it's best to eliminate that possibility, even if the charger is saying everything's A-OK, (i.e., 'light going green') - just to cancel the possibility of that variable.

Mattman, yours i'd guess is the batteries.

If Lasermodder's is dying progressively every time he turns it on, that could be catastrophic failure of the diode and it slowly going LED. A passive component slowly losing conductivity (SMT capacitor?) could also be causing what you're seeing, Lasermodder, or, actually -- a melting/charred/over-currented spring or switch. It's hard to say without some troubleshooting. If it's an "end cap clicky" host, (I believe the Power Rock is) try bypassing that variable completely by taking off the endcap and shorting the battery terminal to the casing. If it's still dim, then the driver would be the place to look next.

The thing to remember is, don't worry too much: most of the time this stuff is replaceable.
 

Lasermodder

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Well, after a while, rechargeable batteries can end up just holding a 'surface charge', meaning a charged area gathers near the anode and cathode but the rest of the cell is pretty much dead. The charger will still see it as charged, but it won't be.

When that happens, the phenomenon is, you get a short burst of nominal current, then it dies off. So it's best to eliminate that possibility, even if the charger is saying everything's A-OK, (i.e., 'light going green') - just to cancel the possibility of that variable.

Mattman, yours i'd guess is the batteries.

If Lasermodder's is dying progressively every time he turns it on, that could be catastrophic failure of the diode and it slowly going LED. A passive component slowly losing conductivity (SMT capacitor?) could also be causing what you're seeing, Lasermodder, or, actually -- a melting/charred/over-currented spring or switch. It's hard to say without some troubleshooting. If it's an "end cap clicky" host, (I believe the Power Rock is) try bypassing that variable completely by taking off the endcap and shorting the battery terminal to the casing. If it's still dim, then the driver would be the place to look next.

The thing to remember is, don't worry too much: most of the time this stuff is replaceable.
Thanks for the reply! :thanks: So I took a wire and bypassed the switch completely and its still dim and getting dimmer, so I charged the battery and put it in, and it looked dim, then I took it out and tested it with my multi meter and it read 4.17 :banghead: so how do I inspect the driver?
 
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lazeerer

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At 4.17v you should not be seeing it dim like the way you say.

What kind of battery is it. 18650,10440,16340 etc.? What Brand Also.

Your battery might also not be able to handle the currant draw anymore. Which alot of Cheap cells cant handle depending on the driver as well as old cells.


Replace the battery like aryntha said. That should be your issue.

What laser is it that you have.? DO you have a link.?
 
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n2stuff

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Well, after a while, rechargeable batteries can end up just holding a 'surface charge', meaning a charged area gathers near the anode and cathode but the rest of the cell is pretty much dead. The charger will still see it as charged, but it won't be.

When that happens, the phenomenon is, you get a short burst of nominal current, then it dies off. So it's best to eliminate that possibility, even if the charger is saying everything's A-OK, (i.e., 'light going green') - just to cancel the possibility of that variable.
would be the place to look next.

Yuup. What he said. I have seen this lots of times with all types of batteries over the years in the R/C hobby.......

Your volt meter will not put the battery under a load so will not get a true voltage reading...
 
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Lasermodder

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At 4.17v you should not be seeing it dim like the way you say.

What kind of battery is it. 18650,10440,16340 etc.? What Brand Also.

Your battery might also not be able to handle the currant draw anymore. Which alot of Cheap cells cant handle depending on the driver as well as old cells.


Replace the battery like aryntha said. That should be your issue.

What laser is it that you have.? DO you have a link.?
Sure here you go.
Power Rock 1W Blue laser torch /Focusable/ waterproof [OL-PRBL1000] - $152.99 : Zen Cart!, The Art of E-commerce
 

Mattman420

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Being that the laser and battery's are both brand new I'm gonna assume its the low quality overall of the pen laser.
 

lazeerer

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n2stuff

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Being that the laser and battery's are both brand new I'm gonna assume its the low quality overall of the pen laser.
Never assume. How many things have we all bought that have failed at 1min. 1 hour,day,month.....
 

Lasermodder

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YAY! It was just a conection problem between the battery and driver! :yh: Thanks for everyones help! :thanks:
 

Mattman420

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I've kinda exhausted my options. I've checked and rechecked all connections. Batteries are in good working order and it all seems to work fine except that immediately when it's turned on its noticeabley brighter for less then a second and dims. It's most likely a small drop in mw but I still hate seeing it happen. I'm thinking it has something to do with the driver?
 

DrSid

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One laser I have behaves like that often .. and it is bad contacts. Especially aluminum on different metal. It just has to be tightened again.
At currents we use all connections have to be perfect.
 

Benm

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Contact resistance can be a problem indeed. In most high current connections it seems to mostly resolve itself, but cleaning battery and switch contact can'd do much harm.
 




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