Short Wave Converter (T987E)

The conversion range of this circuit depends on the coil. The circuit uses two tubes, and the power supply is not provided.

Complete Timer (CB18775E)
This circuit has an LED indication of the timing progress, having been found in an old...
Infrared Vision (CB24310E)
This circuit is from a Radio Electronics magazine from August 1974. It used one of the first...
Nicad Automotive Charger (CB9538E)
This charger is powered by the car's 12 V socket, the number of diodes being calculated according to...