[mythtv-users] Re: New MythTV Hardware Review

Brad Templeton brad+myth at templetons.com
Fri Dec 10 19:52:51 UTC 2004


On Fri, Dec 10, 2004 at 10:29:35AM -0500, Joseph A. Caputo wrote:
> 
> This is how I understand it (from one layman to another):
> 
> If you have digital cable, the digital channels (typically channels < 
> 125 are still analog NTSC, even if you have a digital subscription) use 
> QAM.  I'm not clear on whether it's the QAM signal itself or the MPEG-2 
> content that's encrypted (if at all), but in any event the FCC 


Actually, what I see from comcast is NTSC analog channels, and channels
72 and up, plus 33, are QAM transmissions with up to 20 SD channels per
major channel.  (I was not aware that QAM had so much extra bandwidth.)

The vast majority are encrypted (yes, it's the mpeg) but a number of
the locals are in the clear and several are HD.

In one exception, channel 33-1 is NBC-HD and 33-2 is ESPN-HD.  It's in
the clear.  The "exception" is both the low channel and the non-OTA
channel.

Of course it varies in other cable companies, but from what I see they
are getting large numbers of SD channels per QAM signal (more than 4
certainly) and so I presume the entire digital cable lineup is there,
encrypted, but perhaps I am wrong and other parts of it need to be
enabled or go in a band my QAM-cable capable TV can't tune.

Please note I do NOT have digital cable.

The original poster talked about how to combine his antenna and his
cable.  The point is if your pcHDTV tuned QAM from your cable, you might
not need to have an antenna.  THe poster was presuming he was keeping
the cable, as I assume most people are, in order to get, but not
record at HD, the non-broadcast channels.


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