[mythtv-users] Re: New MythTV Hardware Review

Brad Templeton brad+myth at templetons.com
Mon Dec 6 07:54:42 UTC 2004

On Mon, Dec 06, 2004 at 12:56:42AM -0500, Randy Carpenter wrote:
> What are the chances of us being able to get a card that will accept ATSC 
> over cable (using a cablecard) ? That, along with satellite, have to be 
> the vast majority of the market. Do many people really use OTA antennas 
> for HDTV? For me, personally, it would be useless, as I only have 1 local 
> station that would even be broadcasting in high def.

ATSC is in fact the only reason people are putting up new antennas.  If
you get satellite, you must use an antenna to get your local stations.
The satellite companies don't have the bandwidth to feed all the locals
in HD, not yet.   For your HD-cable, you can get it without an antenna.

The protocol for that is called QAM, it is different from ATSC and DVB.
Whether they would let you put a cablecard into a PC and an open
source PVR is an interesting question.

Anyway, the pcHDTV card we are all talking about is rumoured to have
QAM support in development, so it could tune your cable and you
would not need an antenna.  As to when, who knows?

The QAM signal for your local stations should be unencrypted.  The
non-local stations are typically encrypted (even though you're paying
for them) just to be annoying.  (It's an illusion they have that if
they do this they won't get people making copies of programs that
show up on the net.)

> What about using FireWire to capture? Many HD receivers have FireWire 
> outputs. In fact, if I remember correctly, the FCC requires cable 
> companies to supplied FireWire-equipped boxes for the purpose of being 
> able to record.

Sadly, the protocols include copy protection, so no open source
decoding of the firewire stream.   In theory, if they do non-protected
firewire on the broadcast shows you could get that.

Now you might think, why not let me record the encrypted stream and
feed it back later to the cablecard?  Their plans include timestamps
in the stream to have it refuse to play it delayed, to stop people
from building PVRs.  (Because open PVRs might let you record pay per
view to play back again and again, instead of just once.)

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