This circuit is for traditional old-style telephone lines found in an American 1980s documentation. Components are common and the optical coupler can be replaced with an equivalent.
The purpose of this circuit is to add millivolt scales to a common multimeter. Used transistors are...
June 2017 - The new EEH-ZK (Type V) hybrid conductive polymer capacitors from Panasonic with...
This circuit can measure voltages from 0 to 10 V with a very high input resistance. The circuit is...