
We’ve featured loads of DIY spy projects before and this FM microphone bug is the perfect miniature build for remote audio spying. The extremely detailed 16 page tutorial walks you through building the transmitter which is tiny yet capable of transmitting a signal several rooms away. It reminds me of “The Thing” which was a non-powered spy device used by Russians during the cold war.
While this project isn’t worthy of use in international spying, it’s a great exploratory build to learn about radio frequencies and FM communication.




































