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laser tv-b-gone
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laser tv-b-gone

by crash893 on Fri Nov 30, 2007 8:11 pm

Does anyone know if you could use this kit to drive a IR laser

if so what type of laser would you buy (wavelength) and where would you get it.

I don't want to put an eye out or anything so like 5mw or whatever a standard red laser pen is should be fine.



im trying to turn a tv off at a few hundred yards.
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by magician13134 on Fri Nov 30, 2007 10:03 pm

It's a very interesting idea. I'm not the person who would be able to say if this would work or not, but I can't see why not. All I know is the http://mfgcn.com/ sells some cool laser modules, pick up a <5mW red with adjustable focus. Then follow this tutorial: http://www.instructables.com/id/Laser-F ... ht-Hack!!/ (curse those exclamation marks, you'll need to copy and paste to get it all)
simply replacing the banned burner diode with a CD player diode. Should cost <$10 total, not too bad a loss if it doesn't work.

(Make sure you read the comments, never attach a diode to batteries without some form of regulation circuit)
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by crash893 on Mon Dec 03, 2007 4:33 am

does anyone know what wavelength i would need?
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by maltman23 on Wed Dec 05, 2007 3:17 am

As far as I know, most IR receivers in TVs work at 940nm.

Mitch.

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by magician13134 on Wed Dec 05, 2007 9:24 pm

Aw, most IR lasers from CD players are 808nm I believe.
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by caladan on Mon Dec 17, 2007 6:17 pm

Well, it didn't work with 780nm laser. Gonna look for "longer" one. It seems that those filters in receivers are quite good and cut out almost everything except 940nm.
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by maltman23 on Tue Dec 18, 2007 1:42 am

I've been able to turn off some TVs with 850nm emitters, but the range isn't very good.

I don't know much about lasers, but some people who seem to know what they're talking about told me that the green laser pointers are twice the frequency of IR lasers, and that they double the frequency with a crystal or ceramic resonator, and that if you take out the crystal or ceramic resonator, you get an IR laser. Does that make sense to anyone?

I'll add another note of warning here: please be really careful with IR lasers, since you don't know where they're shining, and it is pretty easy to damage eyeballs if IR laser light reflects off of something by accident and shines into someone's eyes.

Mitch.

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by dar on Tue Dec 18, 2007 4:56 pm

DO NOT USE THE DIODE FROM A GREEN POINTER!
The frequency conversion in green pointers is a very inefficient process so the laserdiode can be very powerful (sometimes 0,5 to 1W), very dangerous since you only se a red glow but not the beam!
Secondly, you will have some problems getting lenses to focus it, expensive stuff.

It's propably better to go with more powerful leds and drivers for them to get better range.
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