This circuit was found in Sgnetics documentation from the 80's. The circuit also has loudness control. The power supply must be symmetrical.
Found in the 1995 Encyclopedia of Electronic Circuits volume 5, this circuit has a constant...
What is the voltage of a zener diode recently removed from the scrap box and without any markings? If...
This simple multitester tests continuity, semiconductors, leaks, and other common component...