This circuit was found in the January 1989 issue of Radio Electronics magazine. The circuit sends audio signals by modulating a low-frequency carrier through the power grid.
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...