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ArcticMyst Security by Avery

$10 (£5) Laser Power Meter - Eh? What's the catch?

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Aug 16, 2007
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Ok, I figured I would need a laser power meter, as it's alright me slapping a "200mW" title on my DIY red.
But they are really quite expensive for a decent one.

So, I scoured eBay, and this guy from Canada is selling Laser Power meter modules for $10 and up. They look like a glorifiyed LDR with perhaps a pot hidden in the heatshrink to callibrate them. Basically you connect it up to a 9V batter and plug it into a cheapo multimeter, set it to the 200mV setting, and shine a laser at the sensor. Then if the multimeter reads 24.5mV, you have 24.5mW of light. They are all aparently callibrated on a Coherent meter.

It's a nice idea, but sounds too good to be true - what's the catch!?!?!?! :-?

Ok, time for some links:
All of them: http://search.ebay.com/search/searc...action=compare&copagenum=1&coentrypage=search

30mW Version: http://cgi.ebay.co.uk/30mW-Calibrat...ryZ14954QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

70mW Version: http://cgi.ebay.co.uk/70mW-Calibrat...ryZ14954QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

120mW Version: http://cgi.ebay.co.uk/120mW-Calibra...ryZ14954QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Sorry for the REALLY long links.

It says that you receive a "free" instruction guide when you buy (which is nice of him ;D )
However, being the skeptical type, I've emailed him for a copy before I buy.


Apolagies if you've all seen this before. I bet it's someone on this forum who makes and sells them!!! :D


Dan :)
 





H

High_Octane

Guest
Re: $10 (£5) Laser Power Meter - Eh? What's the ca

I would wonder if the battery voltage being different would effect the measurement.
Probably better off buying a good one from this forums Group Buy.
 
Joined
Aug 16, 2007
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Re: $10 (£5) Laser Power Meter - Eh? What's the ca

Ahh... after reading ALL that, it looks like a no go.

Thanks for your advice before I wasted £10!


Case Closed! :cool:
 

Rhith

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Jul 13, 2007
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Re: $10 (£5) Laser Power Meter - Eh? What's the ca

I've seen stuff like that and I guess it would be "decent" if you're measuring something like a laser from DX but, as said before, if you want to know true readings get one from the group buy.
 




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