Signaling Devices

Spies rely on signals to send important messages and convey vital information. Learn about signals used in the world of spying and create your own device!

Resources

Tree Stump Listening Device

This solar-powered concealment device was used to intercept radar & communications signals. Learn more about the Tree Stump Listening Device here.

Clock with Concealed Receiver

This CIA designed clock held a secret receiver inside that Moscow agents could use to send signals to meet.

Create Your Own Signaling Device!

Build a signaling device to “tag” a moving car, mark a dead drop site location, or send a signal from a rooftop at night.