This is the basic configuration of an operational amplifier sample & hold circuit. The FET and transistor are commonly used. The circuit is from an 80's documentation.
This circuit was found in an American 1980s documentation. The integrated circuit used is uncommon...
The sensor for this circuit is a phototransistor. We found it in the April 1971 issue of Radio...
We found this circuit in an old Signetics documentation. The integrated circuit is of the time,...