[mythtv-users] Possibly a "dumb" question

Brian Wood beww at beww.org
Fri Feb 5 16:07:27 UTC 2010

On Friday 05 February 2010 08:56:51 am Devin Heitmueller wrote:
> It's also worth noting that cable boxes still do quite a bit of work
> transforming the signal (assuming you have digital cable).  They take
> the MPEG stream, decrypt it, decode it, deinterlace it (if necessary),
> rescale it, and send it out to the TV.  It is not a straight
> passthrough.

Also be aware that cable systems do not carry signals the way they are carried 
through the air, digital cable uses QAM, which some TVs can accept, but using 
that mechanism to deliver the signal to the TV set would preclude the cable 
system's "security", they would have to provide everything to everybody.

The STBs are a large revenue stream to the cable companies, one they are 
reticent to lose.

The cable companies do not want the STBs to be "optional", too much money at 

The only way to take advantage of the ATSC reception capability of your modern 
TV set is to connect it to an antenna, assuming there are signals to receive 
where you are (I have a grand total of *one* such channel available).

Technically the cable companies could use ATSC modulation on their wires, but 
they won't, they want "control", and they want to be able to cram in more 
channels than ATSC would allow, with a reduction in quality, which they 
usually fail to mention.

An ad for our local cable outfit accuses the satellite companies of 
"aggressively processing" their signals, if that isn't the pot calling the 
kettle black I don't know what is.

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