On Sat, Dec 5, 2009 at 1:44 PM, faginbagin <[email protected]> wrote: > I have an HVR-1600 that can't find three clear QAM channels. Using > information from silicondust.com, I think these channels are on frequencies > 543000000 and 549000000 (analog cable 77 & 78). I can see these channels on > HDTVs in other rooms of my home. And the HVR-1600 can tune 8 clear QAM > channels on 5 different frequencies: > three on 93, 639000000 > one on 94, 645000000 > two on 102, 663000000 > one on 106, 687000000 > one on 118, 759000000 (although this one is video on demand and is noisy) > > So I guess I'm wondering if you can offer any insight as to why I'm having > trouble with frequencies 543000000 and 549000000. Could it be a clue as to > whether the problem is the coax cabling leading to the HVR-1600, an issue > with the PCI bus, or just the fact that a PCI card doesn't have the > shielding an HDTV has? > > FWIW, I have yet to try connecting one of my HDTVs to the same coax input. > However, I did try connecting the HVR-1600 to the same input used by my > cable modem back in March/April (should be cleanest coax connection in my > house) and MythTV's scanner couldn't find these three channels there. It's > been so long, I don't remember if I tried the scan utility with that > connection. My focus at the time was an issue with audio noise on some > analog channels (which Andy was able to fix, Many Thanks). > > TIA, > Helen > > P.S. Thought Devin would like to know his recent cx18 fixes have improved > signal quality on the clear QAM channels I can tune. Tuning 7 channels for > about 23 seconds each and playing with mplayer 3 seconds after tuning > (excluding video on demand), I found that: > - Signal strength reported by azap increased from an average of 12c to 13F > - Reports of non-zero BERs and/or UNCs dropped from 6 in 147 samples to 1 in > 147 samples > - mplayer reports of 'a52: CRC check failed!' dropped from 24 to 2 > > Subjectively, the audio and video quality is better. And MythTV seems much > happier as it's less likely to dump core playing back recordings from two of > these channels.
Hello Helen, Thanks for taking the time to try out my patches before writing the mailing list - since that would have been the first thing I suggested. I would suggest trying the following: See if the results differ with /usr/bin/scan. This could be some issue with mythtv's channel scanner. Try an actual TV and see if it can receive the channel. Try the HVR-1600 under Windows, if possible. As far as I know, the Linux driver is at the point where it should behave identically to the Windows driver, so if there is some inconsistency, I would definitely be interested in hearing about it. Devin -- Devin J. Heitmueller - Kernel Labs http://www.kernellabs.com _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
