How to: Laser Microphone for Long-Range Spying
Here’s a super simple laser microphone project which is fairly easy to construct, yet is still impressive. This laser microphone is a covert surveillance device which uses lasers to capture vibrations from a smooth surface. The bounced signal is then converted into an audio signal by a receiver. Check out the build instructions to make one or yourself for under $20.
- Don’t Miss: All of our Laser Hacks
An invisible infrared laser is used to detect the vibrations of the window. A phototransistor picks up the reflected infrared laser light, and an LM386 audio amplifier is used to convert the signal into audio. While this laser powered spy device is not a new invention by any means (the ideas has existed since the 1940s), it’s still a fun and rewarding DIY security weekend project.
Popular Spy Projects:
September 28th, 2010
Long Range? The creator of the device says otherwise.
September 28th, 2010
If you have a more precise laser, you can make it travel long distances. Check out the “Origins” section here and read about the KGB – http://en.wikipedia.org/wiki/Laser_microphone#Origins – A far more impressive and innovative spy project was created by Theremin (yes, the musical instrument was named after him). Read more on that here – http://en.wikipedia.org/wiki/Thing_%28listening_device%29