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ArcticMyst Security by Avery

How to turn power DOWN on cheap greenie?

Joined
Dec 27, 2011
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I bought a couple of cheap (New Wish) <5mW greens for my (3 & 5 yrs-old) kids. They already have a 3mW and 5mW 635nm but I wanted to get them some greens to play with as well.

Unfortunately, it is hard to find on-spec greens. These came in at 12mW and 15mW.

What would be the easiest way to detune them down around 5mW.

I have thought about trying to get a cheap neutral density filter and install it in the aperture.

Any other easy ways to do this.

I tried running 1.3v eneloop rechargeables to see if that might work, but they still put out the same mW.

Thanks!
 





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A ND filter is all i can think of. The only other method I can think of is just turning the current down on the pot. IF there is even one. Alot of the greens i took apart (especially the really cheap ones) did not have a pot.
 
Joined
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The new "newish" pens don't have pots anymore.

TBH there isn't really that much difference in danger between a 5mW and 15mW.

If you're concerned (as I would be too with young kids), you should maybe grab a couple of these?

Link.

Btw, I ended up spending $50 myself on a radioshack pen, just to make sure that when I go out, and if someone wants to see a laser, I can give them one to play with, without being paranoid. I lpmed them to confirm they weren't overspec.

Edit: I need sleep so this could be retarded... but it could be an option... what's the min input voltage needed for them? Try with a spacer and a regular AAA, or a spacer and a nimh for even less?
 
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I haven't tried a single AAA or an AAA Li-ion, good idea.

I did try the ~1.3v eneloop rechargeables and it didn't make a difference vs ~1.7v alkalines though.
 
Joined
Dec 11, 2011
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Just insert a high value resistor in series with the battery to limit current to the driver. It's a cheap green so there won't be any switchmode circuitry inside. Just limit battery current.
 
Joined
Mar 27, 2011
Messages
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I haven't tried a single AAA or an AAA Li-ion, good idea.

I did try the ~1.3v eneloop rechargeables and it didn't make a difference vs ~1.7v alkalines though.

A lithium would provide more power if anything, I mean nimh AAA, like the eneloops. One of those with a spacer. I imagine if the laser still runs, the power will be reduced.
 




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