This circuit was found in an ancient American documentation. The power supply is not given, but we have the voltages used. The relay is sensitive type for high voltage.
Obtained in a 1968 Electronics World, this circuit uses transistors from the time and the sensor...
This circuit was found in an American magazine in 1976. It doubles the frequency of TTL signals in the...
This circuit for the 27 MHz or 11 meter-band had its assembly described in an article in Radio...