This circuit that appears in several versions in this section and on this website was found in documentation from the 1980s. The transistors can be of any general purpose NPN type like the BC548.
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...