<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Arial; font-size: 12pt; color: #000000'>First of all, thanks for trying to help me!<br><br>Well, let me try to describe the picture that I am getting:<br>It is fine for about a second and then it starts getting artifacts, blurring, green blocks,<br>freezes, then it comes back for a second, then goes bad again. I get audio only during<br>the "good" seconds, otherwise, no audio. My receiver (myth box is connect through S/PDIF)<br>keeps switching between Dolby Digital (when there is good sound) and Pro Logic (the default)<br><br>This happens on all channels that I have tried. On the other hand, the TV on the same channels<br>with the same cable/signal gets good picture and sound.<br><br>As far as the firmware, I just downloaded the firmware package from pcHDTV.com and diffed it<br>against the firmware installed on the system and they were identical.<br><br>I am in the Bay Area, California and I used the following settings for the frequencies and scans:<br>General settings -> us-cable<br>Input Selection->Scan for Channels->Cable-High and QAM-256<br>The signal comes from the cable TV coax and not an antenna and I am scanning for all the channels<br>from the Extended Basic Cable Lineup which Comcast switched to digital late last month (channels<br>30-85 from the old Analog lineup).<br><br>I am not sure whether that is correct but Cable-IRC-High seemed to produce the same results<br>and Cable-HRC-High didn't find any channels at all.<br><br>I should also mention that the HD3000 does not find all the channels that the TV finds. For most<br>of the channels that are missing from the HD3000 scan, it (the HD3000) gets a lock but then it<br>times out with "no tables".<br><br><br>----- Original Message -----<br>From: "Brian Wood" <beww@beww.org><br>To: "Discussion about mythtv" <mythtv-users@mythtv.org><br>Sent: Tuesday, September 22, 2009 5:02:33 PM GMT -08:00 US/Canada Pacific<br>Subject: Re: [mythtv-users] Very poor picture quality from HD3000<br><br><br>> ----- Original Message -----<br>> From: "Brian Wood" <beww@beww.org><br><br>>> I know the signal strengths reported by some cards can be misleading, I've<br>>> heard some cards do not really implement that feature, and indicate the<br>>> same strength no matter what is fed to them. I'm pretty sure the HD-3000 is<br>>> one of those, though it may have been the early drivers and not the card<br>>> itself.<br><br>On Tuesday 22 September 2009 17:23:02 voidtrance@comcast.net wrote:<br><br>> The numbers are from the the little dialog that pops up in mythtv-setup<br>> during the channel scan. Both signal strength and S/N are in percent.<br>> It could be that the bar that represents S/N means db (so 13db, if that<br>> makes any sense - I am not a signals guy) but the character after the bar<br>> is '%'.<br>><br><br>What does the picture look like? Are you getting blocking? Green blotches? <br>What is making it "poor"? I understand it can sometimes be hard to describe.<br><br>In the analog world a 13db. video (not RF) S/N would be unwatchable, but with <br>digital RF TV signals it might well produce a usable result. The thing about <br>digital is it looks great right up to the point where it becomes total crap, <br>a "cliff" threshold.<br><br>I think the cards that purport to tell you the S/N are actually using the BER <br>(bit error rate) to approximate the S/N, which involves some assumptions, but <br>is reasonable.<br><br>How is the audio? Can you even decode it?<br><br>I guess I can't ask you to get out your oscilloscope and tell me what the eye <br>pattern looks like, but you should be able to get a usable picture from an <br>HD-3000 if the signal looks OK directly into a TV set and you have >90% <br>signal on the scan. I have got good pictures with approx. 55% on the scan.<br><br>I assume you're using the latest firmware for the card? I haven't kept up, so <br>I don't know what's current.<br><br>I also assume you are using the correct frequency table for your source (cable <br>or broadcast).<br><br>The damaged frames you are getting certainly look like a signal problem, are <br>we talking OTA or cable here (ATSC or QAM)? I'm assuming you're in the USA by <br>your email address.<br><br><br>-- <br>Brian Wood<br>beww@beww.org<br>_______________________________________________<br>mythtv-users mailing list<br>mythtv-users@mythtv.org<br>http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users<br></div></body></html>