This circuit was found in an American 1980s documentation. It analyzes the exhaust gas of a vehicle using a special sensor. The indicator is a milliamperimeter.
The components of this circuit are from the time of its publication in the 1980s. Modern...
This circuit was found in the National component manual which is not currently simple to obtain....
September 2016 - It can be obtained from Mouser Electronics modules with 2.4 inch from 4D Systems...