Combine an amplified listener and a short-range FM transmitter into one “novel” project with Covert Listening Book. The latest in our beginner-friendly series of Weekend Projects, this project does require some light soldering and fine tuning, but once you’ve gathered all the parts, it won’t take long to build. Place the circuit inside a hollowed out book and stow it on a shelf disguised by other books. Then, with the aid of a radio receiver that you’ve tuned to the transmitting channel, listen in as even whispers are amplified into discernable conversations.

This project will show you how to combine two readymade components into a new device. We built ours into a hardcover book, but the circuit could just as easily be enclosed inside a stuffed animal or a plastic toy. Just don’t use anything metal as it will limit the range of the transmitter. And if you come up with a new design for this stealthy listening device, send us an email about your build.


See all of the Weekend Projects posts