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Sounds like that incidental phase distortion must be similar to IM distortion in audio. I bet that I've seen this in older sets and thought it was localized purity problems due to mask doming on strong beam current on bright fleshtones. NTSC color transmission fascinates me as much now as it did 20 years ago. I,ve met a lot of good bench techs that really don't fully understand color transmission and reception but are competant none the less. I'm just a restless inquiring mind I reckon. One of my pet projects that I've already taken one stab at is a homebrew matrix adder similar to the one in a CT-100 that I want to apply after a Zenith Beam demod. section just to see what improvement it would have over the typical 60's crt matrix. I've got a copy of the schematic for 15" Zenith set and it appears that is what they were doing there. I'm hoping for an all tube circuit that will come close to those tight black levels and improved gamma that I see on those first gen. chromacolor sets. If that works out, maybe add driven clamps for DC restoration ( I,m gettin a little carried away now..). Anyway, it seems to me that the luma/chroma area of a color set has to have some complexity for a good picture. It seem to me that the "simple" one tube approach in those old Motorola's an Maggies just didn't cut the mustard to my eyes. They should have stuck with cloning RCA's ( i'll still keep em around, space permitting).
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