Obtained in MIT documentation, this 4-stage circuit has high gain for small signals. The power supply sources 150 V.
This circuit uses an operational amplifier to modulate the light emitted by an LED with audio...
We found this circuit that makes use of CMOS technology in a 1988 publication. The circuit has...
Suggested by Siliconix in 1980s documentation, this circuit uses currently uncommon components. The...