This circuit is part of an oscilloscope project with the PC. Its purpose is to record a peak in a signal that is to be displayed. We found it in the Radio Electronics magazine of February 1990.
I found this circuit on a December 1976 Radio Elettronica. The Italian magazine no longer exists, but...
This circuit was found in a 1976 NASA manual, making use of components of the time. The transistor...
This circuit is a variation of the common grid dip meter, having been found in a 1975 publication on FETs....