Found in a 1967 EEE, this circuit uses the signal from the alternating current power grid to produce pulses from a Unijunction. The circuit is directly excited by the mains voltage.
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...