Stereo FM Transmitter (CB8459E)

This circuit was found in a 90s Radio Electronics. The FM encoder or multiplexer is an uncommon component today.

Solar intercom (CB20503E)
This circuit can be used in demonstrations or science fairs. The circuit uses headphones and can...
Long-Range Wiretapping (CB19321E)
We found this wiretapping circuit in a publication from the 90s. The circuit allows the cable...
Tone activated Triac (CB7234E)
This circuit uses a resonant reed switch at the trigger frequency. The circuit is from General...