This circuit was found in an 80's Electronic Engineering. The circuit uses operatives of the time that are not common today. The power supply must be symmetrical.
This simple metal finder uses a 100 uA indicator. The exploration coil must be constructed in a...
This resistance meter has a linear scale, converting resistances to voltage. The operational...
This circuit was found in a 1995 documentation. Its purpose is to indicate voltage levels that are...