XTAL oscillator with fine tuning (CB22403E)

We found this circuit in an old English documentation. The integrated circuit is of a specific type of the time.

PLL (CB7971E)
This common operational PLL circuit was found in a Popular Electronics 90’s. The power supply need...
CMOS Continuity Tester (CB16563E)
This circuit found in a 1988 documentation, uses a piezoelectric or crystal capsule as a...
Light-sensitive circuit (CB23962E)
We found this circuit in a Radio Electronics issue from July 1969. The lamp remains on until C1...