This converter has coils according to the reception and converted frequency bands. We found it in the October 1989 Radio Electronics magazine in an article that teaches its construction.
This is a very simple motor drive circuit with an LDR. The circuit simply powers a small motor. We...
This plug-in control was found in General Electric documentation from the 1970s. The SCR can be...
This circuit from an old 1978 publication uses germanium transistors but can be implemented with...