Today this frequency corresponds to the end of the FM band. However, in December 1958, when the circuit was published in Radio Electronics magazine it was the frequency used by American satellites.
Found in an Electronic Design from the 90's, this circuit uses common components. The circuit is...
When the sensor receives light, the relay closes its contacts and remains so even after the light...
This circuit produces pulses of 90 V at intervals that can reach 5 minutes. The circuit is from a...