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 simple calibration circuit consists of a crystal oscillator that generates an accurate 100 kHz...
This circuit generates 5 notes in sequence, which are programmed in the connections of the 4017...
This circuit makes use of comparators and common operational amplifiers, having been found in...