We found these circuits in a Popular Electronics from the 90s. The circuit has a simple low power version and a higher power version with MOSFET (VMOS) of the time.
This circuit appeared in the 1991 Electronics Experimenter Handbook. The circuit is for remote...
This circuit was found in Radio Electronics magazine from January 1959. The power transistor must...
This circuit uses an MW radio tuned to around 540 kHz to detect atmospheric signals, for example, from...