Found in the October 1979 Radio Electronics magazine, the purpose of this circuit is to monitor the coolant level in a car's radiator. The circuit is based on the LM1830.
The sensor of this circuit consists of two 1N4148 diodes connected in series. The accuracy of the...
This setting appears elsewhere on this site. This was obtained from an 80's Circuit Encyclopedia and...
This circuit can be used as a direct optical link or by optical fibers. We found it in a...