Found in old American documentation, this receiver transmits signals via the power grid. We can use it on links or remote control. The components admit equivalents.
This simple megaphone is from old documentation, but uses still current components. The circuit is...
The circuit used is the 4093 configured as an inverter in this application from Radio Electronics from...
This AC motor driver circuit was found in Motorola's 1968 documentation. No information was given...