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By the way, the differences in color between chassis have a lot to do with the color demod gains and angles as well as the phosphors. The "deep" reds in a properly adjusted CT-100 are as much due to the use of a standard NTSC chroma matrix as anything else. In later sets with sulfide tubes, the green is yellower, which means that turning on the green gun is also adding some red to the color. This would mess up flesh tones, so an adjustment is made by increasing the R-Y gain, thus turning off some of the red whenever the green is turned on. However, this has the opposite effect on red colors, turning the red on excessively and making reds overly bright. This defect would not occur if picture tubes were linear devices. It is the picture tube voltage-current characteristic ("gamma") that makes the gun turn on more strongly than expected and turn off less strongly than expected. This brightness distortion in different colors is the trade-off in order to make hues roughly correct with the new green phosphor (especially to maintain the natural variations in flesh tones). There is an opposite effect on saturated cyan colors, which are reproduced too darkly.
PAL solved this problem by setting the camera matrix to match the newer phosphors. Thus, PAL receivers cannot reproduce the saturated "NTSC green" either, but at least the saturated colors are all the correct brightness and hue. Same goes for HDTV - the camera matrix has been correctly specified for the modern phosphors.
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