This circuit sounds when the input voltage drops below the value determined by the zener. The circuit is from a 90s American documentation.
Other operational amplifiers from the same family such as MC34002, MC35001, MC34004 and MC35004 can...
This oscillator uses germanium transistors. It was found in the Radio Electronics magazine of may...
This circuit is from a documentation on Motorola interfacing techniques from 1975. The Darlington may be...