This circuit has an interface for a multimeter or electronic voltmeter. We found it in a 90s Electronic Engineering. The sensor is an unusual component today.
This circuit is from a 1967 US publication. The configuration can serve as a basis for designs...
This circuit came out in a 1983 English magazine, but it can be easily assembled today, as the...
We found this circuit in a 1966 documentation. The circuit is intended for a door opening system by the...