In the figure we have the way to obtain the Exclusive-OR function with 1 transistor. The circuit is from a 1964 Electronic Design. The transistor can be any general purpose PNP.
This commercial circuit is from a Japanese magazine from 1967. It uses germanium transistors, and...
This circuit can be used to drive relays, solenoids, motors and other loads according the...
This circuit is based on the small keychain that responded to the sound of a whistle and were...