[mythtv-users] hdtv from a cable box

Chad masterclc at gmail.com
Wed Jul 6 21:16:08 EDT 2005

On 7/6/05, SamS <sams2100 at samspam.net> wrote:
> I can't seem to find a clear answer on this, so I'll just ask.
> Currently, I have a cable box that I control with an IRBlaster so that
> mythtv can change the channels and all that.  Works great.  Now that I
> have a new HDTV big screen, I would like to order the HDTV channels from
> Comcast.  This would mean a new cable box.
> Is it possible to control an HD cable box with an irblaster and capture
> the HDTV output using a card like the pcHDTV HD-3000 just like I am
> currently doing with my PVR-250 and the old cable box.  Or is the only
> HD content I will ever be able to capture going to be the OTA signals I
> get from the antena?
> It just seems like it would work the same since the HDTV signal coming
> out of the cable box to the tv could just be captured by the myth box in
> the exact same way the old pvr250 did, right?  I'm not trying to capture
> the output with a firewire cable or anything fancy like that.
> Thanks to everyone for all the great help I have received from these forums!
> Adam
> _______________________________________________

I have thought about this, and seen some replies that would confirm
what I think.

If you have your HDTV cable box decoding the signal, you don't need an
pcHDTV3000 to capture it.  Any capture card would do, your existing
PVR-250 for example.  However..

To capture a truly High Def image, you would need a capture card that
captures Component/DVI/HDMI input.  That's a CAPTURE card that
CAPTURES those formats, not an Nvidia with DVI Out, this is just for

So I would think, in theory anyway, that you could indeed capture it. 
You'd send the signal via whatever transport you have on your cable
box (maybe an Svid-out) to your PVR, and then out to your TV via
whatever you currently use.  This would mean degredation, but it would
probably still look a WHOLE LOT better than standard on a High Def TV.

Just a thought.

The other side of the answer that I've seen on the list is basically:

If it's encrypted, nope.  If it's not, using QAM through HDTV capture
card might work.  My understanding of this route is that you bypass
the cable box, plug the cable directly into the HDTV tuner card, and
go from there.


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