The purpose of this heat detector is to find hot spots on a board or other locations. The sensor is an integrated circuit from the period. The circuit is from Radio Electronics from May 1985.
This circuit uses reed switches as sensors. We found it in a 1992 documentation. A float at a...
One of the problems with analog multimeters is the non-linearity of the resistance scale. This...
I found this circuit in an old English magazine from 1979, but it can be easily assembled with...