This grounding test circuit was found in an American 80's documentation. The circuit is for the 110 V power grid but can be changed to the 220 V power grid.
May 2017 - Texas Instruments' new OPAx388 operational amplifiers can now be purchased from Mouser...
Based on components from Linear Technology, we find this circuit in a 2005 manual. The circuit...
This circuit was found in an American documentation from 1969. Indications of the used transistors are...