Found in 1965 Radio Shack documentation, this circuit has a crystal phone output in the 14.8 kHz range. The coil consists of 200 turns of wire 25 in a 1.5 m side square.
This circuit with 5 V power was suggested by Motorola's Linear Databook of 1990. The circuit has...
We found this circuit in a 1982 documentation. An intercom to be good must be sensitive and have...
This circuit is indicated to determine the flight time of an electric motor model airplane. The...