Using an operational amplifier of the time, this circuit was obtained from a 90s Radio Electronics. The circuit covers the frequency range from 2 Hz to 20 kHz.
Found in a 1980s documentation, this circuit uses a photo-Darlington. There must be an optical...
We have here an ultra-simple amplifier stage of just one transistor, which can have some uses on...
This conventional window detector circuit was found in a 1995 documentation. The trigger points, that...