Found in an American circuit manual from the 1970s, this circuit can use any general-purpose transistor. The operating frequency range is from 600 to 4000 Hz.
This circuit appeared in the June 1990 issue of Radio Electronics magazine. Integrated circuits must...
Lockout shooting, due to the incidence of light, can be achieved with the circuit in the figure. In...
This circuit can function either as a crystal or galena receiver with a pre-amplifier using a FET...