Driver for oscillograph (T459E)

This circuit from an old MIT documentation excites an oscillograph element, an old waveform viewer.

Zero crossing detector (CB3887E)
This circuit appears in several configurations in this site. This is from American documentation from...
STK984 190E Integrated Power Module (COM160E)
November 2016 - Mouser Electronics is making available the new N Semiconductor STK984-190E power...
Heterodyne Mixer (CB4291E)
This is a typical 80's FM radio mixer circuit. The circuit was found in a documentation of the...