This circuit was found in a 80’s American documentation. The adjustment trimpot is from 47k to 100k. The diodes are general-purpose types use and the supply voltage depends on the relay.
The circuit shown in the figure converts an input voltage into pulses of proportional duration. An...
This double T oscillator configuration can employ operational diamonds and the symmetrical supply...
Found in a 90s Popular Electronics, this circuit provides a current of 3 to 5 A depending on the...