This circuit is from a 1924 book by Gernsback. The receiver uses two tubes and listens to headphones. Power is supplied by battery with the indicated voltages.
This circuit was found in a 2005 Linear Technology manual. It senses the two-way current,...
This circuit was found in an Electronics Now from the 90's. See the previous article for the...
This is the basic configuration of a monostable TTL with the 74121. The trip is done with an NC...