This circuit has 4 operating modes and was found in the 1995 Encyclopedia of Electronic Circuits Volume 5. The circuit works with light or heat sensors.
This circuit was found in a 1973 Radio Elettronica magazine. The Italian magazine no longer...
This filter was found in an 80's English publication. However, it can be implemented with modern...
The circuit shown enables dynamic diode testing with an oscilloscope. We found this configuration in a...