Found in an American circuit manual from the 1970s, this circuit can use any general-purpose transistor. The operating frequency range is from 600 to 4000 Hz.
This contact or reed switch actuation was found in a 1964 Electronic Design. The circuit can be...
This circuit was found in an English magazine from 1973. The magazine no longer exists, but the...
This experimental flip-flip changes its state by the command of two push-buttons. The state is...