We found this time base circuit in a timer project from the August 1972 Radio Electronics magazine. The circuit takes advantage of the 60 Hz signal from the power grid.
The figure shows how to use a 3-winding transformer to switch outputs with different voltages by...
This 80's circuit, suggested in Texas Insrtruments documentation, uses a Hall effect sensor. The...
This circuit was found in a 1966 publication. Its purpose is to identify high voltages by lighting a...