This circuit for old analog telephones is from period documentation. It controls a relay that can be used to turn the extension on and off.
This circuit provides a power of the order of 2 W, characterized by high performance. The output...
This 12 V to 110 V inverter with 100 W was found in a 1977 Signetics manual. The transformer must...
The gain of this amplifier is given by the components indicated in the formulas next to the...