We found this circuit in documentation from the 1980s. It is an input stage for a digital frequency meter. The circuit can operate with signals up to a few tens of megahertz.
This VCO makes use of an RC4558 which is an operational amplifier with characteristics close to...
This circuit can operate with different voltages, depending on the zener used. We found it in a...
This circuit can be used in the car to control the windscreen wipper or with other appliances at...