This circuit has a visual indication of activation and is suitable for people with hearing impairments. The circuit was found in the March 1974 issue of Radio Electronics magazine.
Suggested to power the previous circuit, this power supply was found in the December 1990 issue of...
This is a very useful autotransformer circuit on the bench. We found it in the September 1970...
This circuit was obtained in a 1960 documentation of General Electric. It is applied in the...