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FIOS TV pixellation fix - attenuate to SNR 31

Discussion in 'TiVo Series3 HDTV DVRs' started by AbMagFab, Nov 19, 2007.

  1. holee

    holee Uncertain

    4,381
    0
    Dec 12, 2000
    Raleigh, NC
    As a soon to be HD TiVo user with Verizon FiOS, you guys are doing an amazing job of making me panick. Potentially annoying to unusable service. Not having happy thoughts. :(
     
  2. webin

    webin New Member

    307
    0
    Feb 13, 2008
    Hillsboro,...
    Keep in mind we aren't posting about all the beautiful channels we are seeing (well, some of us are). The pixelation stuff is only on a few channels, and most people aren't seeing it. I wouldn't recommend worrying until (if) you actually see if on your setup.

    Be sure to let us know how your install goes tomorrow (or whenever it comes).
     
  3. richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
    I have to admit that I'm a little concerned as well. We currently have Comcast, but Verizon is spray painting various colored stripes all over our streets and driveways in preparation for FIOS in our neighborhood. I was initially jumping for joy, but I'm a little worried now.

    Currently everything we have is almost perfect, but I understand that Comcast is beginning to compress their HD even more now (to be able to brag about having more HD channels at the cost of PQ) and I'd really love to have the huge "pipe" that FIOS offers for broadband. But all of the attenuation and macroblocking talk is putty a big wet blanket on things.

    Webin, you say you're "near Portland". Where exactly and how would you rate your overall experience w/Verizon and FIOS? TIA!
     
  4. gamo62

    gamo62 New Member

    497
    0
    Oct 12, 2002
    $100 off your first bill! How much IS your bill?
     
  5. rifleman69

    rifleman69 Member

    853
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    Jan 6, 2005
    Oregon


    FiOS is head and shoulders above Comcast and DirecTV (IMO) that it's not even funny. You will notice the picture quality difference in both HD and SD broadcasts. Didn't know that L.O. was finally getting FiOS, that's great news!
     
  6. richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
    Good to hear and I think we'll take the leap when it's available. I know most of the people that find their way here have a problem and only account for a very small percentage of the TiVo/FIOS population...but some of the stories are real nightmares and I can sympathize with their frustration. People that are happy with everything rarely end up posting on forums like this.

    Not sure when it'll be ready at our house, but our streets sure look like a graffiti artist has been busy!
     
  7. webin

    webin New Member

    307
    0
    Feb 13, 2008
    Hillsboro,...
  8. richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
  9. Apr 6, 2008 #169 of 866
    sweh

    sweh New Member

    12
    0
    Jul 22, 2005
    Colour (I'm English) me confused.

    I thought the ONT converted from incoming optic to coax. So how can the strength of the signal change? I'm really confused.

    Anyway, to my real problem.

    At this moment I have tuner 0 tuned to 170 (429Mhz; Comedy central) and the signal strength is changing from 100 to 93 to 87 to 61 to 43 (eep; just hit zero) and back to 100. SNR is bouncing from 37db down to 33db and back. It has 28,000 RS uncorrected (increasing by 100 or so every second) and 620,000 RS corrected (increasing by 1000 every second).

    But at the same time tuner 1 is tuned to 825 (717Mhz; TNT HD) and is a rock solid signal strength 100 and with SNR bouncing between 36 and 37dB with an (unchanging) 255 uncorrected errors over the course of 1.2 hours.

    Now for an experiment, I just changed tuner 0 to 169 (627Mhz; BBC America) and am now also getting solid 100 with SNR 36/37. So I don't _think_ it's a cable card issue.

    Could this be Verizon being bad on Comedy Central? Or could it be the signal is "too hot" and needs attenuating? Some of my symptoms appear to match the too hot side (high SNR, RS uncorrected increasing) but why does this only impact some channels, and why does the signal strength keep changing?
     
  10. Apr 6, 2008 #170 of 866
    Marc

    Marc Active Member TCF Club

    14,760
    1
    Jun 26, 1999
    McMurray, PA
    This is exactly the symptom of a "too hot" signal coming in to the TiVo.

    I had the same problem. I think that the displayed SNR value caps out at a maximum value, and the actual value is higher.

    I ended up adding 11 dB of attenuation before my SNR finally showed a drop, but even then it was just 2 or 3 dB on the screen. At that point, my error rate finally stopped increasing and stabilized.

    I think that the signal strength affects certain frequency rather than others, so you'd see the problem on some channels but not others.
     
  11. Apr 7, 2008 #171 of 866
    webin

    webin New Member

    307
    0
    Feb 13, 2008
    Hillsboro,...
    Update on my setup: I initially reported that I was experiencing macroblocking on CW (in HD), but that swapping the ONT fixed it. As time has gone on, I've encountered macroblocking on several channels, as least CW and Fox (both HD). I haven't really had time to diagnose the problem and figure out the full range of channels I'm getting it on, but I'm sure it's the same hot signal problem. When I finally get some time off (dern deadlines), I'm going to get some attenuators and knock the signal down.
     
  12. Apr 7, 2008 #172 of 866
    sweh

    sweh New Member

    12
    0
    Jul 22, 2005
    Ok, thanks. I've ordered a set of attenuators and will play with them when they arrive. 10:30pm on Wednesday on Comedy Central seems a good time for problems.
     
  13. Apr 8, 2008 #173 of 866
    rcr2

    rcr2 It's you, not me.

    104
    0
    Feb 3, 2007
    Monmouth...
    I just got FiOS and (knock on wood) have had no problems. Installer said the signal was coming in very hot, too, so I was worried, but everything seems to be running a-ok.
     
  14. Apr 8, 2008 #174 of 866
    rashid11

    rashid11 New Member

    30
    0
    Apr 3, 2008
    I had to add 8 + 8 + 3 + 3 = 22 Db of attenuation to drop the SNR to 33 Db !!!
    These 4 attenuators was what FIOS guy gave me when he did the install. I guess
    I have to spring for an extra one or see if local RatShack has the variable attenuator.

    The fact my Tivo HD was showing 38 Db originally prolly means that it is the max
    value it will display (some folx reported seeing 39 Db).

    About attenuators reducing the noise along with the signal - they do reduce incoming noise, but the "native" thermal noise of Tivo's own RF stages is not affected and stays constant (within reasonable temp range).

    About macroblocking - even with my extremely hot signal, most channels seemed to be OK. But, I _did_ see totally random pixelization/macroblocking on different channels. Hopefully it is gone now ... I'd still like to get down to the "golden" 31 Db SNR number
     
  15. sweh

    sweh New Member

    12
    0
    Jul 22, 2005
    Stage 1 test; 1 put in a 20db attenuator and the system wouldn't tune into anything at all. It could be a bad attenuator, or it could just have degraded the signal too much.

    So I put a 10db in. Now on Comedy Central the signal strength bounces between 68 and 75, and the SNR bounces between 32 and 33dB. A little high compared to what others have written, but in the past 12 hours there have been zero Uncorrected errors on that channel. RS Corrected goes up occaisionally (4180 in 12 hours).

    (Annoying design; the cable input is very close to the eSATA connector, and wobbling that cable caused the box to reboot; the TiVo eSATA port is a little too loose).

    Hopefully this has solved my problems and I won't need to add in a second attenuator.
     
  16. richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
    It's more likely that the cable's connector is the culprit. You might want to replace it with the recommended SIIG Serial ATA external cable...less than $10. Other cable recommendations (Section III, #26)
     
  17. shaggy2002

    shaggy2002 Member

    46
    0
    Dec 15, 2007
    Last night I noticed that one of my cable cards was no longer working in FIOS. I attemted to run Diags and it stayed at please wait forever. I had to hard boot the tivo and when it came back both cards were working again and I thought everything was good until I started flipping between Showtime, Starz and they all were pixalating every 10-15 seconds. ON local channels HD and SD I experience no pixelation. I never had a problem before with my SNR prior to the card quit working. It is doing this on both cards as well. Is there anything I can check to determine what my problem may be? or do I need to call FIOS?
     
  18. rudolpht

    rudolpht HD Maven

    36
    0
    Mar 8, 2003
    We'll I have one of these (at about 60% between min & max) plus a 6 DB pad.

    I am truthfully amazed at the change (HBO HD, BBCA, 5starmax were my bad channels). I actually just bought an HD Tivo to replace a S3 because my other TivoHD was showing stability until a few recent recordings. I need to get more Pads in and then I should be set (fixing the S3 and my other existing TivoHD) and the new replacement HD Tivo gets returned unopened. I'm getting signal that bounces between 68 and 72 but steady at 31 SNR. I'll fix up the existing HD Tivo also (unless you thin it's OK to attenuate before the splitter) (2 Tivos (HD & S3) , data, and 1 Fios HD DVR box)

    Side item: I was having lots of issues with 8.3 and I'm wondering now (after I replaced the HD) if I shouldn't go back to my old one that had the nightly reboots (or toss it into an enclosure and try to make it a second drive married to my already larger drive in the S3).

    THANKS!!!!
     
  19. webin

    webin New Member

    307
    0
    Feb 13, 2008
    Hillsboro,...
    I have been using a 10db attenuator to help with my pixelation. I still get minor pixelation on some channels... notably FoxHD, and will also get signal drop out from time to time, where sound and video cut out for a few seconds (on any channel, even FoxHD). I chalk it up to bouncy signal strength, and was planning to try 8db at some point.

    Anyways, onto my question. I woke up this morning and was getting the grey screen with a "can't find signal" message. My cable cards were showing signal strengths of 45 and "-". I took the 10db attenuator out of the line, and the video signal returned (though I didn't check strength).

    The question: Have cable attenuators been known to go bad? It seems like a fairly simple piece of hardware, so I wouldn't expect much failure, especially after months of use. I think it could also be a suddenly weaker signal from Verizon, but haven't had time yet to look into the issue.
     
  20. Thos19

    Thos19 Member

    169
    0
    Dec 31, 2002
    Rockland, MA
    I've had FiosTV since March and experienced pixelation for the first time last night. Thanks to this thread, I was prepared with attenuators, and fixed the problem...for now.

    What is bugging me is this: Why did I not have a problem for the first few months? It seems like it should be either my signal is either too hot, or not. It shouldn't suddenly manifest itself out of the blue. I doubt that Fios suddently decided to boost my signal yesterday and cause the problem. If it is the tuner section in my Series 3 being inadequate to the task, is it a function or the circuitry "wearing out" over time from receiving a hot signal, and the eventual solution will have to be a new tuner board? Or perhaps the next generation of Tivo will be the solution as it may or may not have a better built tuner section?

    Very strange...

    Thos.
     

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