We found this circuit in American documentation from the 1980s. Transistors can be of general use. The frequency range of the generated signals ranges from 500 kHz to 10 MHz.
This circuit deactivates devices powered by the power grid so that when the power returns, they do...
The trigger signal for this circuit is an audio tone. Tones up to close to 100kHz can be used. The...
Found in the March 1974 Radio Electronics magazine, this circuit is designed to measure the level...