Re: Speech sensors?

[herbgottlieb@juno.com]

> Does anyone know if the following technique is for real or is an urban
myth: that >industrial-espionage type sensors exit which can reconstruct
an internal >conversation from the remotely-sensed vibrations of a room
window?
> Margaret Mazzolini
I once tried it with a 5mW HeNe laser and a photocell to detect 
vibrations reflected from the window glass.  It didn't work for me
but it might work with an optical system to concentrate the 
reflected light on the photocell and sensitive amplifiers at 
the receiving end.

Herb Gottlieb from New York City
(Where commercial spies do not readily share their secrets)