We found this circuit in the May 1990 issue of Radio Electronics magazine. The circuit is powered by the relay used and uses both normally open and normally closed sensors.
This simple circuit for switching RF signals was found in an RF Design from the 90s. The circuit...
I found this circuit in a Popular Electronics from 1992. The circuit can be easily implemented with BC549...
This circuit was found in a 90s EDN. Its purpose is to increase the efficiency of operational...