This circuit was suggested by an Electronic Design from the 90s. Its purpose is to detect resistance relationships in circuits with resistive sensors for control purposes, by firing a relay.
This circuit from a June 1957 Radio Electgronics is for oscilloscopes of the time with a maximum...
This circuit is from an English magazine Radio and Electronics Constructor of November 1978. The...
This circuit was obtained from a Linear Technology manual from the 90's. The integrated circuits are...