Modulator Amplifier (V1574E)

This circuit is from a 1938 tube manual. Transformers are the critical components. Component values are given.

Power Supply with Operational Amplifier 12 V x 500 m (CB1171E)
This circuit was found on a Radio Electronics of July 1984. It consists of a source with the 741...
Full bath indicator (CB6952E)
Found in an Elektor from the 90s, this circuit triggers a Sonalert-type buzzer when the sensor is...
120 V x 40 W x 400 Hz inverter (CB7271E)
This circuit was obtained in Motorola documentation from 1969. The components are from that time. In...