Diode Tester (CB22137E)

This diode tester was found in an English publication from the 1980s. Transistors are general-purpose types of the time.

High Output Voltage Amplifier (CB6179E)
This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply...
555 Duty Cycle Oscillator (CB24846E)
This circuit was found in the September 1984 issue of Radio Electronics magazine. The circuit has...
Simple Battery Eliminator (CB23694E)
This circuit is regulated by zener and provides a voltage of 9 V. The circuit is from a Radio...