This circuit is from a March 1978 Radio Electronics magazine article that showed how to build it. The circuit is TTL based and is powered. The components used can still be found.
This circuit is from an 80's documentation. The transistor can be any general purpose PNP and the...
This powerful pushbutton uses a power MOSFET. We found it in a Popular Electronics magazine from...
This shield circuit for lamps and other charges was found in a Popular Electronics from the 90's....