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Both my Panasonic plasma and Samsung LCD take over 15 minutes to scan the QAM channels. On NTSC scans it is not nearly slow. Just wondering if that is typical or if the last 2 model years have improved in that regard.
 

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This is typical.

Your television is scanning from 50MHz to over 850MHz--a rather huge swath of spectrum. Since a tuner can only look at one "channel" at a time, you can imagine why it can take a while to scan....
 

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^^^^
There's a similar large block of spectrum for analog too. TVs still scan up to 69, so that's 69 x 6 MHz = 414 MHz. Ch. 69 is 800-806 MHz. Also, with OTA, there's the same number of possible RF channels for analog and digital.
 

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OK so NTSC scans 414 MHz and QAM 800 MHz. But why does is take 10 times as long?

Also, Why are QAM sub-channels enumerated to a thousand?
 

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How slow is the NTSC scan? QAM extends beyond 850 MHz. Even if your provider does not support above 850, some providers go to 1004 MHz and beyond.
 

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Discussion Starter #6
NTSC scans at about 3 channels per second. Definitely less than a minute to go up to channel 125.
 
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