Combination Color and Contrast Control

[Electronic M]

Originally Posted by old_coot88

Do you mean mechanically ganged together on the same shaft? Or done electrically in a switchable 'preset' mode?

The RCA prototype model-5, CT-100 based on it, some of the 21CT55s based on it, and some other sets based on those usually had 2 chroma level controls, one mechanically ganged to the contrast the other independent.
I suspect the reason this faded was a he desire to reduce cost and complexity...the CTC-5 and 5 were both cut down designs from their predecessors.

The OP is incorrect in assuming this practice died with the early color sets. I own a 1971 Zenith 12B13C52 hybrid color TV and it has no contrast control, but instead a control labeled "Chromatic" that control is a 2 gang 1 knob pot that's both 1 of 2 color level user controls, and the only contrast knob....Just like a CT-100 only with a gimmick name that clues the user in to what all the control does.
There may be other examples in newer and older sets, but the Zenith is the one I know about for sure.