Comments on: Laser surveillance defeater

By: David

David — Thu, 26 Jun 2008 03:23:01 +0000

@11

Anything that diffuses light (like frosted glass or a screen) limits the effectiveness of a laser mic. The angling of the window idea could be effective. To pick up the reflected light, you usually have to have the laser and receiver perpendicular to the window and close to each other.

Angling to window either up or down (i.e. making the reflected light return to a point well above or below the laser) could make it very difficult to pick it up as it's a lot harder to move around vertically than horizontally to position the receiver.

By: static

static — Wed, 25 Jun 2008 05:12:58 +0000

Neither a hack or a DIY project is it? Ant way probably if anyone who hangs around hackaday already knows how to roll their own if they needed one.

By: Solenoidclock

Solenoidclock — Wed, 25 Jun 2008 04:45:15 +0000

You could just get a spotter scope and learn to read lips. Also, I wonder how well a laser microphone would work on a slightly diffuse surface, or through a screen? Angling the windows might also shoot the reflection out of range, and using a bubble window might spread the light too much to deal with at a considerable distance.

By: BigD145

BigD145 — Wed, 25 Jun 2008 02:46:19 +0000

I’d rather have a few soundbites that repeat over and over, but with random intervals between bites.

I’m not your friend, guy. I’m not your guy, buddy. I’m not your buddy, friend.

By: David Mudkips

David Mudkips — Wed, 25 Jun 2008 01:38:42 +0000

This device is essentially useless.

Their own promo says, "this device was engineered to defeat such filters by centering its frequency output at the middle of the human voice range..."

By tuning it to a particular frequency, they've actually made it easier to filter out the noise it generates.

Real "window buzzers" produce a spectrum of randomly varying frequencies that cover more than just the normal human vocal range (to cover harmonics, not just base frequencies).

This might flummox amateurs who don't know how to post-process audio to clean it up... but that's about it.

By: jo

jo — Wed, 25 Jun 2008 01:27:01 +0000

Hey miked, how about giving ourself a hack from your own ?

By: miked

miked — Tue, 24 Jun 2008 18:41:59 +0000

i do not approve of this post.

it is a commercial post.

By: mike

mike — Tue, 24 Jun 2008 17:57:55 +0000

The sad thing is that they actually make laser microphones that are meant to be serious pieces of equipment, not just little toys like this.

By: fartface

fartface — Tue, 24 Jun 2008 16:46:35 +0000

Simpler solution, place a $1.00 used transistor radio against the window tuned to static and turned up.

By: hal h

hal h — Tue, 24 Jun 2008 16:26:50 +0000

Wow. How much for that? You could tape a headphone in a suction cup for that. Or....

http://www.thinkgeek.com/electronics/audio/6bd8/

... You could give yourself a fun speaker set. Just turn on some rap at low volume and the people listening will wonder what the hell you are saying.

(Oh yea, and at a third the cost you get _2_!)

By: twistedsymphony

twistedsymphony — Tue, 24 Jun 2008 16:15:39 +0000

or you could… I don’t know, turn on a radio and talk quietly

By: johnnyscolex

johnnyscolex — Tue, 24 Jun 2008 15:03:28 +0000

wouldnt a small vibrating device taped to a window work just as well to completely throw off the listening device?

By: Alex

Alex — Tue, 24 Jun 2008 12:53:13 +0000

that whole thing is $5 worth of parts including the pcb.
someone who made the diy laser system should test to see which frequency is best at jamming it.