We found this circuit in the Philips integrated circuits manual of 1990. The circuit must be powered by a symmetrical high current source. The integrated circuit must have a good heat radiator.
This circuit was found in a 1992 documentation and has excellent sensitivity, using components that...
We found this circuit in an old American documentation. The circuit applies to modern equivalent...
This circuit was found in an English publication from the 80's. It triggers a buzzer (with...