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 oscillator was found in a 1976 documentation. The no specified components indicate circuit...
This circuit activates a buzzer when the voltage applied to the input falls below a preset value in...
This protector was found in an Electronics Now from the 90s. The 250 V transient suppressors are common...