One-transistor oscillator (CB22064E)

Capacitors C2, C3 and C4 determine the frequency of this simple oscillator. Transistor can be general purpose equivalent.

Wrong Voltage Alarm (CB4478E)
This circuit has an interesting application. If a device with the selector switch in the 110 V...
MW direct amplification radio (CB18314E)
This simple radio circuit was obtained in a Japanese publication in 1967. The circuit uses...
Proximity alarm (CB21300E)
This circuit was found in a Popular Electronics from the 90's. The components used are common and...