[mythtv-users] tuning two-card systems ?
mythtv at ultratux.org
Tue Oct 19 19:59:18 UTC 2004
On Tuesday 19 October 2004 16:53, Michael J. Lynch wrote:
> Adam Felson wrote:
> >You're still misreading your cpu useage. There's *absolutely* no way
> >you're running two cards with no cpu useage. Impossible. Absolutely.
> >When I ran two cards on an Athlon XP 3000, I typically got 30% useage
> >for the card processes alone and another 25% per transcode process. If
> >I did mpeg4 encoding in real time, I got 30%/card.
> >Nowadays I'm running two pvr-250s an one bttv (bt878) card.
> He said 0% IDLE not 100% idle. Anyway, it's hard to believe that he's
> not getting
> any jerking, hiccups, or artifacts when there is no CPU time left.
Yes! Thank you. Hope that finally clears that up.
About the hiccups, I have now noted some blips in the audio, like when
sentences are cut short or words concatenated. Not too obvious, but it's
certainly there. So that explains everything.
> >>I notice that my two bttv cards are not what you'd call exactly in
> >>sync, where the tuners are concerned. If one card gives good picture,
> >>the other is just slightly off-channel so the colors are too
> >>pronounced, or I get stripes and other interference. Now what I wonder
> >>is this, can one finetune channels per-card, or is the channel
> >>frequency globally defined for all cards ?
> >I've never had color problems. Perhaps you have a defective card or are
> >running an old version of video4linux.
Nope. The cards are not defective. I have three cards here, and just for fun
I had their channel freqencies printed out when perfectly tuned. You'll note
that each card has just ever so slightly different frequency:
Haup TV express MIRO PCTV Pinnacle PCTV
247.0625 247.6250 247.2500
263.0000 263.6250 263.2500
Resulting in B/W, stripes, no sound, bad picture, etc.
> >You shouldn't need per/card finetuning as they're receiving the same
> >signal. Spend the $35 and replace the defective card.
That's easy for you to say. Of course they receive the same signal, but here I
am, TELLING you that despite that, I see small tolerances in their tuning.
Are you saying I'm making all this up ? You sure seem to be.
But okay, let's suppose you are right and I am wrong. Can you then please
tell me which two of the three cards I tested are the defective ones, and
thus which card left is the only good one ?
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