1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

FIOS TV pixellation fix - attenuate to SNR 31

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

  1. Feb 7, 2008 #61 of 866
    richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
    SNR of 35/36 (or higher) is above the "sweet spot" of 31/32. It may be enough to cause problems. Cableco's are famous for just increasing the signal strength rather than fine-tuning it to the ideal. I'd have another go with the cable guy again...and this time ask for someone that understands cable cards and TiVo. If it was good for a while, something is changing to cause problems. It may well be that something is wrong with TiVo but until everything is right from the cable company, that will be hard to determine.

    If you have a TiVo case number, keep it open and if you can't get satisfaction from the cableco ask TiVo for a three-way call so you, the cableco and TiVo can all be on the line at the same time.

    Hang in there...it can work! With four-million + subscriptions I guess there will be some problems and it's too bad that you (or anyone) has to go through these sorts of things. You have my sympathy and I wouldn't blame you if you bailed, but it might be worth another look.
     
  2. Feb 7, 2008 #62 of 866
    ilh

    ilh New Member

    377
    0
    Dec 21, 2007
    Hold on a sec. If he is seeing 0 uncorrected RS errors, how can this be a signal problem (too hot)?
     
  3. Feb 7, 2008 #63 of 866
    AbMagFab

    AbMagFab What happened, TiVo?

    3,638
    0
    Feb 5, 2001

    If you see 0/0 on the RS items, then it's a source problem, not a Tivo or signal problem.
     
  4. Feb 8, 2008 #64 of 866
    richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
    That's pretty much my take on it too.
     
  5. Feb 8, 2008 #65 of 866
    darthplagueis86

    darthplagueis86 New Member

    7
    0
    Jan 29, 2008
    Ok, the cable guy is coming out again(for a 5th time) and I noticed that my RS corrected/uncorrected numbers have gon efrom 0 from last night, now they are at 400-600 range. I will tell the cable guy to check the signal source, as you reccomended. I'll let you know what he does. I hope this works this time!!!
     
  6. Feb 8, 2008 #66 of 866
    richsadams

    richsadams Active Member

    8,893
    2
    Jan 4, 2003
    IIRC the recommend signal strength should be -10 to +10 dBmV with a SNR of 31-32. The tech should be putting a device on the line at the TiVo connection point to measure the signal. To address these issues most cableco's will simply increase the signal strength which may work for their own STB's and DVR's (particularly one's w/o cable cards) but too strong a signal (just as too weak a signal) can cause havoc with TiVo.

    The RS corrected/uncorrected numbers indicate a signal/tuner issue for that particular channel at that particular time. It's possible/probable that you would have seen an erratic SNR at that time as well.
     
  7. Feb 10, 2008 #67 of 866
    darthplagueis86

    darthplagueis86 New Member

    7
    0
    Jan 29, 2008
    Now my tivo won't even receive any HD channels at all. I called tivo, they insists that the cable cards need to be paired up, then I call verizon to ask them to pair them up. Verizon will not provide any support at all because it is a tivo product, and the cable cards have already been swaped, the lines have been checked, and the signal is fine. So basically, I have no service at all on my tivo hd channels, and neither compnay will help me out. I have a $800 tivo box, which does not work, and it not eliglbe for return. What to do???
     
  8. Feb 10, 2008 #68 of 866
    ciucca

    ciucca New Member

    270
    0
    Jun 29, 2004
    Did you try the attenuator work around? You can order from smart home.
     
  9. Feb 10, 2008 #69 of 866
    darthplagueis86

    darthplagueis86 New Member

    7
    0
    Jan 29, 2008
    yes, no luck..just made things worse. on the right now with tivo/verizon trying to get my cable cards paired up...that is what tvio says will fix the problem, but verizon will not pair them up, just activate them. This is hell!!
     
  10. Feb 10, 2008 #70 of 866
    ciucca

    ciucca New Member

    270
    0
    Jun 29, 2004
    let us know what happens. As far as I know Verizon does not pair the cards to the device. In the CC menu on my TIVO, in "the conditional access" menu. The "host validation" is unknown 00. I would be interested to know if pairing actually makes a difference. I have heard that Verizon is not able to pair the cards at this time in their system, but may be able to by the end of the year.
     
  11. Feb 10, 2008 #71 of 866
    ochlocracy

    ochlocracy New Member

    5
    0
    Jan 18, 2007
    I’ve been working on trying to solve my problems for weeks now, and I think I finally got this band-aid fix to work. I’ve done a lot to get my Series 3 & Tivo HD to work with FiOS. I just wanted to make a post here with all the information I’ve collected because I think it could help lead to a more permanent fix.

    When I first got my series 3back in June I had pixilation on almost all my SD channels, none on my HD. After a month or so it went away on it’s own and worked great up until Dec. Since Dec. I’ve had the problem on about a dozen SD channels, still all of the HD are fine. After reading through all of the information here I found the attenuator fix, but was unable to find the correct combination. I’d get to the point where pixilation occurred once every 5 min, instead of once every 5 sec. which was watchable, but that would drop my signal so low that at certain times of the day I couldn’t tune to some channels ie. HD.

    Without attenuation my signal is great on my all my channels except the dozen or so that pixilate. The good channels are all above 95, and fluctuate between 95-100 every 3-4 sec. The bad channels are all over the board, and fluctuate typically from 40-100 every sec.

    I tried all the things mentioned on the forums; replaced cable cards, replaced splitters, attenuation, ran a direct line to the ONT, replaced the ONT, removed all other devices from the line including ActionTech router, etc.

    So I finally started to investigate this further and found out that the channels I have problems with share the same frequencies. I am in the Tampa area and these are the channels that I have problems with on my Series 3 and the frequencies they run on.

    Tivo Series 3
    Station Freq (Mhz) Channel
    Lifetime 435.000 120
    Oxygen 435.000 124
    Bravo 435.000 165
    Nick 435.000 256
    History 441.000 108
    SOAP 441.000 123
    Style 441.000 140
    Scifi 441.000 160
    A&E 441.000 161
    Toon Disney 441.000 221
    CNN 447.000 80
    CNN-HL 447.000 81
    CNN-WN 447.000 86
    Cartoon Network 447.000 227
    Boom 447.000 228

    I haven’t had time to check every channel one by one, but since I started seeing the pattern I was certain now It’s Verizon signal….or some interference in that range…or tivo doesn’t like that range.

    I had a Verizon tech out here this morning, and the tech turned out of be an old acquaintance so I jumped at the opportunity to bug the hell of him, probe him for information and ask him for as many favors as I could in order to solve this problem once and for all because I didn’t have any luck with attenuation, and was certain my problems lay with their signal. He admitted he wasn’t the most knowledgably person to talk to about why those frequencies were the only ones that were affected but said he would take any information I had and pass it to someone who would.

    I got him to bring out his test meter and plug it into my line. Results showed the signal was anyway from -1db to +2db on the channels he was trained to test, think he said 2, 50, and 2??; so I asked him to punch in 80 and his metered showed -30db, then channel 120 also showed -30s. Now he was unsure if the channel option actually tuned to the actual channel associated for TV signal, but only my bad channels were showing the -30db, everything else was near 0…so... possible more evidence that it’s Verizon’s signal.

    We were unable to solve the problem while he was here, but he did leave me another pile of attenuators so I could continue to play musical attenuators.
    I printed out all the information we had so he could pass it along to another tech. I’m hoping to get a call tomorrow from another tech that understands the cable system a little better, and it willing to work with me on this TiVo issue assuming its Verizon’s signal.

    After he left, I finally decided to see if I could get this attenuator fix to work. I removed all the excess coax and splitters going to other TVs and just focused on my series 3, and after 22.5db worth of attenuation (in the middle of the line, not at the TiVo) it’s the best it’s going to get. There is still pixilation, but it’s minimal, maybe once an hour and my other channels seem to have enough strength @70s with a SNR 32-34. So in my case 31 was not the magic number on my Series 3. (22.5db includes all attenuation from the ONT, all splitters, and attenuators)

    After the success with the Series 3 I went to my TiVo HD to try to get rid of the problems on the two channels. Pixilation solved at 20.5db of attenuation, Signal strength @80s, and SNR of 31-32.

    While I was trying the attenuator fix I called TiVo support in hopes they had a new answer to my problem since the last time I called. The support agent was interested in the frequencies that were problematic, and asked for all the info I had about them so she could pass it along; but still no new information.

    All in all after weeks of trying to tune to SNR of 31 with attenuators, I finally got this fix to work. I still hope to hear from a new tech tomorrow, and try to solve the problem without using so much attenuation, I’ll keep you guys posted. But I’d like to see what channels/frequencies/market others were having their problems I believe it could lead to a more permanent fix.
     
  12. Feb 10, 2008 #72 of 866
    ciucca

    ciucca New Member

    270
    0
    Jun 29, 2004
    I'm am having the same problems with the same frequencies you are, the only difference is that they are mapped to the digital local channels I receive here in NNJ. It's my guess everyone is experiencing problems on the low frequencies, but depending were you are different channels are mapped to them, explaining why it shows up on different channels for different people.

    I think it's definitely the low frequency bands that are having the issue. Sorry the attenuation has not worked for you. I am using 16dbmv of attenuation and although I still get low number of uncorrected errors in the QAM freq range you mention, it is barely noticeable, a few hundreds in a about 4 hours time. Keep trying the attenuators you may need a few db more.

    Good write up. I'm glad you are keeping on top of the issue. I hope it can be fixed in software, but I'm skeptical, I think it is the QAM tuners TIVO uses. I read somewhere that TIVO uses a consumer grade QAM tuner, and Motorola uses a better one. What else explains why the Motorola STBs don't have nearly the same problem. TIVO probably used cheap tuners to save money. I work in the telecommunications hardware industry and I can't count how many times cheaper hardware chips were substituted to save production costs. The majority of the time it came back to bit them, because the chip did not perform to spec.
     
  13. Feb 11, 2008 #73 of 866
    GoHokies!

    GoHokies! O2->CO2 Converter

    2,657
    0
    Sep 21, 2005
    KFME
    Can you explain how test equipment measures all the channels near 0dB except for the "problem channels" (which are at -30dB) is in any way whatsoever related to the tuners that Tivo used in their hardware?

    (hint: Not possible. It's a Verizon problem).
     
  14. Feb 11, 2008 #74 of 866
    ciucca

    ciucca New Member

    270
    0
    Jun 29, 2004
    I can only speak to my house were I am having a similar issue. I have tested the signal and although there are signal fluctuations it is no where near a 30db drop. I and many others that have Motorola boxes and TIVO have a problem with the TIVO. Explain that. Logic tells me if the Motorola boxes work and the Tivo does not , then, well what do you think it is ;)
     
  15. Feb 11, 2008 #75 of 866
    rschare

    rschare New Member

    16
    0
    Nov 28, 2007
    I've read a bunch of these threads. Can someone tell me how to test the attenuation of the signal? Do I do this on different channels? Thank you.
     
  16. Feb 11, 2008 #76 of 866
    ochlocracy

    ochlocracy New Member

    5
    0
    Jan 18, 2007
    I did some more trouble shooting today trying to narrow down the problem.

    I started with the Motorola box. This box sits in a room that no one is ever in so I have not known if there has been any pixilation. Hooked it up; direct line to the ONT no attenuation. So I sat in there watching about an hour worth of TV flipping through the channels, watching the known bad channels for anything. No pixilation occurred during the this time, but I did notice that the pictured appeared to stumble.. Hard to explain, but I figured I was looking to deep into it trying to find anything.

    The Motorola box is a SD box attached to an SD TV via composite so I thought maybe composite might handle the problems (if they were there) differently since it’s an analog signal. So I moved to my Tivo HD and hooked it up with both S-video and composite; pixilation still occurred without the correct attenuation.

    The Motorola box does pixilate when it is first tuning to any channel, but that’s all I could find. I was also able to make it pixilate when I fiddled with the coax, not necessarily the connections, but just moving it around.

    Next I moved onto my Samsung HD TV that had a cable card in the back and had some success. I first ran a direct line from the ONT without any attenuation. Then I stole a cable card from my TiVo HD and put it in the back, and started flipping through the channels. Found some new channels that pixilated, and what do u know the 3 channels I found are all on the same frequency. It appears my HDTV doesn’t like the 777mhz.

    So now of my 3 cable card devices, each of them dislikes it’s own frequencies.

    Here’s my current list.

    Tivo HD
    Station Freq (Mhz) Channel
    WGN 411.000 9
    Comedy 429.000 170

    Tivo Series 3
    Station Freq (Mhz) Channel
    Lifetime 435.000 120
    Oxygen 435.000 124
    Bravo 435.000 165
    Nick 435.000 256
    History 441.000 108
    SOAP 441.000 123
    Style 441.000 140
    Scifi 441.000 160
    A&E 441.000 161
    Toon Disney 441.000 221
    CNN 447.000 80
    CNN-HL 447.000 81
    CNN-WN 447.000 86
    Cartoon Network 447.000 227
    Boom 447.000 228

    Samsung HDTV
    Station Freq (Mhz) Channel
    FUNIMAT 777.000 231
    TVONE 777.000 241
    FAMNET 777.000 212
     
  17. Feb 11, 2008 #77 of 866
    rifleman69

    rifleman69 Member

    853
    0
    Jan 6, 2005
    Oregon

    Yes, under diagnostics in the tivo menu. You can tune to any channel you receive and you'll see how good of a signal is coming in.
     
  18. Feb 12, 2008 #78 of 866
    ciucca

    ciucca New Member

    270
    0
    Jun 29, 2004
    One interesting thing I noticed last night while troubleshooting a QIP6416 issue.
    I was "unscrewing" the cable from the back of the Moto 6416 box and my wife noticed pixelation on the TIVOHD (I have 16db of attenuation on the tivo). I then put the diagnostics screen on the tivo and had my wife remove and replace the 6416 cable in the other room, and the uncorrected and corrected errors started rapidly increasing on the tivo.

    I am going to try to turn off all the other moto boxes I have and the router and see if I still get pixelation without the attenuation. It's possible the 2-way communication and/or the moca on the coax is causing interference the tivo can't handle. Has anyone already tried this test? To be able to test this for a 24 hour period I will have to send the family away for a few days :D Just wondering if anyone tried it, before I start fighting with my family.
     
  19. Feb 12, 2008 #79 of 866
    GoHokies!

    GoHokies! O2->CO2 Converter

    2,657
    0
    Sep 21, 2005
    KFME
    That's a really good thought.
     
  20. Feb 12, 2008 #80 of 866
    ochlocracy

    ochlocracy New Member

    5
    0
    Jan 18, 2007

    Yeah I had my ONT switched over ethernet for my internet so I didn't have to use crappy ActionTech router with the super small 1KB NAT table. So my 1 motorla box no longer receives guide data, and my internet is no longer on the MoCA.

    Didn't fix the problems.
     

Share This Page