This circuit was found in Motorola documentation from the 1980s. The components are of the time, not currently common as operational and opto receiver.
This variable gain circuit for analog video signals was found in a 90s Linear Technology...
In the figure we show how to connect a power MOSFET to the output of a CMOS function to control a power...
This receiver using a FET appeared in a November 1957 Radio Electronics magazine. It is one of the...