This circuit activates a relay after a time given by C1 and R1. The circuit is from a Radio Electronics from December 1974. The relay voltage is the same as that used in the power supply.
This circuit, from a 2002 documentation, checks the logic levels of the inputs, providing a...
Using a dual 555 CMOS this very useful circuit on the bench was found in the July 1998 Electronics Now...
The integrated circuit used in this regulator is quite old. Its 1970s casing is still made of...