This circuit supplies a load at SO1 when the load at SO2 is powered. The circuit is from a Popular Electronics from the 90s. Diodes and triacs must match the loads.
This circuit for a 455 kHz ceramic filter was found in the October 1952 Radio Electronics...
This circuit was found in a Poptronics of the 90's. It can be powered by voltages between 6 and 15...
The microphone of this short-range MW transmitter should be low impedance magnetic (a small...