This circuit is from old American documentation, using a regulator integrated circuit that is uncommon today. The diodes can be 1N4002 and the transformer has a 500mA secondary.
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...