This power supply is based on the 723 integrated circuit, which is no longer very common today. The transistor must have a heatsink and the bridge can be formed by diodes 1N4002 or equivalent.
This amplifier with the RCA CA3018 integrated circuit was found in the August 1970 issue of Radio...
This circuit generates sinusoidal signals that depend on the input oscillator. The circuit is from...
This fast-acting circuit uses any phototransistor as a sensor. The circuit drives a 30 V relay, but...