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Old 07-21-2013, 02:33 PM
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wa2ise wa2ise is offline
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Join Date: Dec 2002
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Quote:
Originally Posted by andy View Post

The second issue is caused by high frequency luma information getting decoded as color. It's unavoidable on a TV without a comb filter to separate the chroma and luma from each other. You can reduce it by rolling off the video bandwidth, but you will lose fine detail.
It's possible to reduce this crosstalk, if you have a source that provides "S-video" aka luma and chroma on separate wires. Before the luma and chroma are merged to create composite video, low pass or notch filter the luma to remove luma above about 2.5MHz. Anything above that will end up as crosstalk into the chroma demodulator, and isn't seen as luma on a set not using a comb filter.

luma---> 3.58 notch filter----> to composite mixer

chroma---> 3.58 band pass filter---> to above composite mixer

And the composite then feeds an RF modulator.
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