Metal detector receiver (CB22457E)

Found at Popular Electronics this receiver is used with a transmitter for quadrature-coil signals.

Walkie Talkie (CB18720E)
The output power of this wireless intercom for the 27 MHz (11 meters) range is in the order of ½ W,...
XOR Gate (CB4812E)
In the figure we have the way to implement an Exclusive OR or XOR gate with CMOS or TTL...
Neon Insulation Test (CB11534E)
This useful circuit is used to test the insulation of cables, appliances, leaks in high voltage...