This circuit was found in a Motorola manual from 1968. As it can be obtained 20 V at 15 kHz from 120 V x 60 Hz. The components are of the time.
This VCO or Voltage Controlled Oscillator uses common components. TR1 can be a BF245 and TR2 a...
The transformer for this project found in a 1986 documentation is an output type, found on old...
We found this circuit in a 1978 documentation. The SCR conducts when the regulator's output...