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.
This circuit is from a technical manual of the 80's. The operational ones are of the time like the...
Based on an LM36000 OTA this circuit was found in the July 1988 issue of Radio Electronics...
This relay circuit with a dual channel MOSFET (not very common today) was found in an old American...