Marconi MkVIII Television Camera CCU drawer 3 open

The main auto registration motors and potentiometers.

The left module has the auto iris, red gain and blue gain.

The center module has the red registration controls and the blue is to the right.
Both red and blue tubes converge on to the green tube signals.

This is a "B" CCU with extra blue and white presets. These correct the differences between the internal diascope and the lens geometry.

It is possible to override the autos and line up manually by rotating the thumb wheels on the potentiometer shafts.