This circuit, which controls both the temperature and the level of a liquid in a reservoir, was found in an Electronic Design from the 90s. The circuit is based on a double 555.
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...