This simple transistor tester was found in a Japanese magazine in 1967. It tests general purpose transistors of both the NPN and PNP type and is powered by 4 batteries (6 V).
This circuit was found in Radio Electronics magazine from October 1964. The circuit uses two...
This 5 V power supply for TTL, Shields and microcontrollers is old, and the components can be...
This automotive alarm uses common components and is suitable for old vehicles. The circuit was...