Medium wave range booster (CB21677E)

This circuit is from a 1960 book by Hugo Gernsback. The transistors are germanium from the time.

Radio without energy supply (CB23729E)
This radio uses the own tune signal to get energy for the transistor. The circuit was found in a...
Current Regulator (CB16036E)
This circuit can be used as a basis for the design of battery chargers with up to 1.5 A of...
Solar tracker for solar panels (CB21025E)
This circuit carries a solar source with the ability to follow the sun in its movement. The...