We found this circuit in a 1956 Sylvania publication. It serves to monitor telegraph transmissions being placed next to the transmitter. The circuit is indicated for the range of 80 and 160 meters.
The circuit below was suggested by the Motorola Linear Databook of 1990. The component used is...
This circuit is intended for testing small capacitors. What we have is an astable multivibrator, which works...
This circuit was found in an American 1980s documentation. The transistorized step is the...