This circuit was obtained from a 1967 GE SCR manual. It is intended for controlling relays responding to a decrease or increase in temperature.
This circuit was found in old American documentation. Transistor is general purpose and relay is...
This simple alarm with latching uses a relay as the main element. The circuit is from a Radio...
This circuit is from an Italian publication called Fare Elettronica from 1987. What we have is an...