[old_tv_nut]

Originally Posted by JBL_1

I would think at this stage all the early color sets all used the same tubes and phosphors and classic chroma demodulator gain and phase.

Yes, no need for non-standard gains and angles since they all used the same phosphors.

Originally Posted by JBL_1

The auto flesh circuits that operated on color difference signals were less obnoxious than those that pulled the color sub-carrier.

Here I disagree. The hue pulling circuit could affect hues around flesh tone without killing greens, cyans, and blues. Effectively, all the linear matrix type auto flesh tone circuits did was to decrease the Q axis gain, so you tended towards either reddish orange or cyan. Depending on how far the manufacturer went with it, you could end up with "the tan cowboy on the brown horse riding into the orange sunset" while trees and grass got desaturated and had a tendency to turn brownish. Engineers never used a set with that "one button auto color" engaged (well, maybe their family members did), preferring to adjust the color when necessary.

The thing about RCA's auto color that I didn't like was the setting of color level based on average chroma level. This resulted in the color level turning up or down based on scene content, and I often saw obvious failures when the scene cut to talent wearing bright red clothing. It did result in "calendar color" (somewhat oversaturated on low-saturation scenes), which the public seemed to like. I PO'd someone I interviewed with at RCA once when I told him this was not a good idea in my opinion.

The hue pulling circuit was invented by my colleague Ted Rzeszewski at Motorola. For some reason, Motorola never used it, but licensed it to RCA.