This circuit was found in a 1968 documentation. It makes use of both NO and NC reed-switches and small magnets attached to a card in the form that results in the drive combination.
This circuit was found in 90s Radio Electronics. The transistor can be any general purpose....
The circuit below shows how to obtain a monostable from a CMOS 4013 flip-flop. The actuation time...
This circuit is from Philips' 60s documentation. The circuit can be applied to modern operational...