We found this receiver on a single chip in the 1976 Siemens integrated circuits manual. The circuit is of the super heterodyne type using ceramic filter in the IF.
This circuit was found in old American documentation. Transistor is general purpose and relay is...
This simple alarm with latching uses a relay as the main element. The circuit is from a Radio...
This circuit is from an Italian publication called Fare Elettronica from 1987. What we have is an...