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Old 10-10-2017, 09:47 PM
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old_tv_nut old_tv_nut is offline
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Quote:
Originally Posted by dtvmcdonald View Post

My personal opinion is that best is to use any two axes and get the response
quite flat to about 700-800 kHz then rolling off to zero at 1.5 MHz. on both
axes. Few folks notice the resulting bleedthrough from I into Q. Using
equal bandwidths the results are identical independent of the axes used.

However, other people may seriously object to the bleedthrough.
Yep. It was less disconcerting to have the color saturation of details reduced than to have the wrong hue - and if the level of quadrature distortion was low enough, at normal viewing distance in the home it appeared to add some color detail without being obviously wrong. With the engineer's nose to picture tube, the quadrature was visible as a rainbow effect on small strongly colored objects, but it also tended to be hidden by the luminance overshoot due to video peaking.

Since later solid state sets usually simplified the chroma bandpass such that they had this gradual chroma cutoff rather than the classic double-tuned response, it meant that they could actually benefit from composite video input that had double sideband chroma, meaning that the color detail would be somewhat better with a digital source (DVD or digital broadcast converter) fed into the baseband composite input than was possible with RF feed.
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Last edited by old_tv_nut; 10-10-2017 at 09:54 PM.
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