Found in 90s Popular Electronics, this circuit fires a load through a MOSFET from an audio signal applied to the input. Power supply is done according to the load.
This circuit was obtained in a 1975 documentation. It is intended for old vehicles that still use...
With this circuit it is possible to select transistors and their compliant test. Or circuit...
This power supply circuit with selectable voltages was found in the June 1979 issue of Radio...