This power supply circuit for high power audio amplifiers was found in Radio Electronics from the 90's. Power MOSFETs admit modern equivalents. The output current is 5 A.
This circuit warns when the headlight bulb is on. We found it in a Popular Electronics from the...
The oscillator shown in the figure keeps its frequency constant in an active cycle adjustment...
This circuit was found in an Argentine publication from the 1970s. The circuit can be assembled with...