I am using a single AverMedia DVB-T 771 tuner card (and no other tuner cards in the system) and would like to ‘compare notes’ with anyone else who might be using this card the same way - to record both from DVB (free to air via the antenna socket) and from Cable (Set Top Box via the S-Video socket) at the same time. This is how I set it up, but I don’t know if I went about it the ‘right’ way, so if anyone knows one way or another, please post.

In mythtv-setup:
1) In Video Sources, I set up two sources, one for my Cable channels and one for my Free To Air channels.
2) In Capture Cards, I first added this card as a DVB card (it’s detected as a Zarlink MT352 DVB-T) and the default input is ‘DVBInput’. Then in Input Connections, I mapped it to my off-air video source.
3) I then went back and added a “second” Capture Card (even though there is only one physical card), this time specifying it as a ‘Standard V4L capture card’ and this time I made the default input ‘S-Video’. In Input Connections, I mapped it to my cable video source.

KnoppMyth now reports that I have 2 encoders installed, and to switch from one tuner to the other when watching TV, I press the keyboard's Y button.
Now firstly, a question which is, did I do this right? (because if so, I fluked it.)
Secondly, to the issue I am having - and that is the DVB quality is significantly reduced whenever I am recording from cable at the same time as either watching or recording off-air. Perhaps this is to be expected, eg. am I pushing things to the limit by recording the two sources at the same time?
And finally, if I am pushing things to the limit card-wise, would I get better performance with a hardware encoding/decoding card like the PVR-350 perhaps?
And finally finally, if I went for something like the PVR-350, would that definitely enable me to record both sources at the same time, like the 771 does? Because I think having a single card playing the part of two tuners is pretty nifty, but I don’t know if it’s actually supposed to work this way or not

I'm pretty sure you can't.

I've got a 771, and a PVR-250, and I've tried this with the 250.

I believe that the cards can only output one a/v stream at a time, so it's either DVB or Cable, not both.

I've ended up getting a seperate BT878 card which I'm going to install at some point.

But yeah, it sounds like you did it right.

_________________
Mephi
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R5.5
Opteron 2.Ghz
1Gb Ram, 200Gb Maxtor PATA
Avermedia 771 DVB-T
Hauppauge Nova-S2 (waiting to be installed)
MS MCE2 Remote

Thanks for that, Mephi. So it sounds like even though I can record both the DVB and the Cable stream at the same time, the card really isn't designed for that, hence the poor DVD stream quality whenever I attempt to do so It just seems odd to me that it's possible at all, if the card is only designed to output one stream at a time

I would like to be able to record DVB and cable at the same time but the motherboard only has a single PCI slot, so I think the solution may to be add something like the WinTV-PVR-USB2, but that's getting off topic so I'll make it the subject of another post.

I have seen some dual analoge/digital tuners cards out there that may be able to do it (you'd have to make sure before you buy tho), but yeah a USB encoder should work.

Unless you've got a firewire output on your cable box, I know a few people have had sucess with that.

_________________
Mephi
-----------
R5.5
Opteron 2.Ghz
1Gb Ram, 200Gb Maxtor PATA
Avermedia 771 DVB-T
Hauppauge Nova-S2 (waiting to be installed)
MS MCE2 Remote