This receiver is from a 1924 Gernsback publication. The receiver has good efficiency when powered by the indicated voltages. Listening is through a high-impedance phone.
This circuit is from the SGS manual of linear integrated circuits of 1982. The L78xx is equivalent to...
This low displacement circuit was found in American documentation from the 90s. Operational...
The purpose of this circuit is to maintain the liquid level of a reservoir between two values...