This circuit consists of an electrostatic sensor that can check if a cable is energized by simply approaching it. The circuit is from an Electronics Now from December 1998.
This circuit is based on the Texas Instruments LMC662 and has the function of monitoring the audio...
Yes, tunnel diodes can also be used in voltage regulators, as shown in this circuit from a Radio...
Based on operational amplifiers of the time, this circuit from the 1980s has high input impedance. The...