This circuit, with printed circuit board included, is from a Radio Electronics magazine from July 1971. The SCR can be any equivalent of the 106 series.
This circuit uses a Norton operational amplifier to generate 1 kHz pulses with a 1 to 60...
We found this circuit in a 1968 US documentation. The power FET is a component of the time and the...
This traditional crystal radio circuit, but which has a modern version with diode, was found in an...