This 50 Hz rejector or notch filter was found in a 1975 documentation. Other frequencies can be obtained by changing components. The filter uses a Wien network and must use a symmetrical power supply.
This circuit was proposed by a 1965 Electronic Design. Its purpose is to widen the line transients...
We found this receiver in old documentation. The transistor is made of germanium and the...
This simple battery tester uses two transistors to drive LEDs of different colors, indicating the...