This circuit was found in an Electronics World of 1968, making use of components of the time, not common today. The power supply is not provided.
This set-rest relay uses two SCR and two switches to control a DC relay. The circuit can be used...
This simple circuit of low power with an LM386 includes the highly sensitive audio preamplifier...
circuit is used to increase the sensivity of a relay. A 50 to 100 mA relay can be triggered with...