Using the CA3140 in the figure we have a comparator that goes low in the window voltage space. The circuit was found in June 1986 Radio Electronics magazine.
This circuit was obtained in a 1975 documentation. It is intended for old vehicles that still use...
This circuit uses a diode as a radiation sensor. The operational ones are old because the...
This circuit was found in the March 1999 issue of Electronics Now magazine. The meter is analog and...