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Discussion Starter · #1 ·
In My local area NBC will hopefully be broadcastin in HDTV soon. My local cable company pulls the Signal from antenna from what I understand and retransmitts it over the cable lines...

does this mean when NBC starts broadcasting in HDTV the antenna based signal that the cable comany is receiving will be forwarded over their network and the HDTV signal will be included?


sorry if this is a dumb question but I am new to this :)
 

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Some cable companies do relay the OTA signal in its original modulation format: 8VSB. If you have an OTA HDTV tuner, a direct cable input to it (or with a 1-GHz splitter) will enable you to tune the OTA/cable signal as you would with a UHF or VHF antenna. (Most H/DTV stations are UHF.)


But cable companies often modify the 6-MHz-wide OTA signal, enabling them to squeeze at least two HDTV sources into each 6-MHz cable slot. Most error-correction data, needed for OTA but not cable's less-noisy medium, is stripped away. Station-ID data (PSIP) is removed, too. Then the signal is remodulated with cable's QAM technique (often digital 256 QAM). You'll need a cable converter for these QAM cable signals. A few new TV sets can handle cable's QAM, but might not handle special scrambling by local cable companies. -- John
 

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Quote:
Originally posted by John Mason
...A few new TV sets can handle cable's QAM, but might not handle special scrambling by local cable companies. -- John
John,


Do you (or anyone else) know why cable companies would scramble local digital channels like they would premiums? I'm no lawyer, but this sounds questionably legal to me.


If not illegal, it is at least irritating as an owner of an Integrated RPTV that will accept QAM cable signals.
 

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Discussion Starter · #4 ·
ok but if ...for example:

NBC is normally on channel 3....and the cable company offers channel 3 will channel 3 be in HDTV? or is it broadcast on channel 53. something and I wont get it since they have another channel on 53 like.... e! or something?
 

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The current analog signal on channel 3 will stay the same. When a station brings up digital, it is transmitted on a separate channel.


If they didn't do this, all of those people with analog TV's would not get any signal.


Joe
 

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Yes, most cable outfits will still have a redundant analog signal for awhile.


In San Diego, HD stations are assigned numbers in the 700 block, so that "channel 8" HD is assigned 708.
 

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If set makers put digital-QAM decoding in their sets, as a few are now, I don't see how cable companies can avoid scrambling their signals. If they didn't, the newer sets could pick up signals that are normally only authorized with current cable converters.


Suspect the newer cable standards, though, developed at CableLabs , have a fix for this to avoid those with new sets tapping into cable lines without paying (possible now with analog signals). -- John
 
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