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So Wayne, what I gather is that RCA did later attempt to improve chroma resolution by again using I /Q demodulation only to find that encoders were not limiting the Q bandwidth to 500kHz?
I always wondered in the latter years of NTSC composite encoding whether the true NTSC specifications for 1MHz I and 500kHz Q were still used. Or because the assumption that pretty well all receivers used equiband narrow band (500kHz) chroma demodulation.
Your reply concluding that the RCA re introduction of I / Q demodulation revealed too much Q component above 500kHz suggests to me that chroma encoding by the 1990s had abandoned I / Q and simply used slightly wider band R-Y / B-Y.
To my earlier question on the visual effects of quadrature crosstalk on transients: how obvious and ojectionable was the crosstalk in the picture? I see no evidence of it on my CTC5 Deluxe which has the wider chroma bandwidth. Perhaps due to an abandonment of I /Q encoding, it is because the encoded signal no longer has an I component from 500kHz to 1MHz?
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