Unlike the previous circuit, the output of this one goes high in the window voltage range. The circuit is from Radio Electronics from June 1986 and is based on the CA3140.
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...