Failed SKY+ recording AND Sun Spots

Discussion in 'Sky Digital TV Forum' started by Eye in the sky, Jan 13, 2005.

  1. Eye in the sky

    Eye in the sky
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    I have a theory here. You guess it! Yes, Sun Spots.

    This thread is related to an ealier thread 'Fail Fail Fail Sky+' http://www.avforums.com/forums/showthread.php?t=178671 or similar thread like 'wipeout'. Thought I should start a new thread for everone in this forum to hear this ridiculous theory.

    Check out this website for some information. There are a couple around but I thought this may be a good one for general but not too technical illustrative purposes. I am not a sunspots guy so may not have too much details or technicality on this subject.

    http://www.dxlc.com/solar/

    Sunspots have been known to badly affect communication, satellite and electrical systems and satellite transmissions. Mobile networks, planes, tvs, etc. Electrical devices must have good EMI/RFI shielding. On a chart on the website, sunspots activity was very high in Nov 2004.

    I am not saying that sunspots 'is' an excuse for electrical faults like recording failure. But no discredit to Sky+, but one question is how well the Sky+ box is shielded for such electrical interference. Does anyone know? Is the HDD shielded? How about the box itself?

    If however, electrical interference could be the issue then Sky+ boxes must be amply gounded to defend against EMI/RFI. This can only be good for us customers.

    If sunspots is the cause for EPG firmware failure (meaning the download stream is corrupted), then I suppose some debugging or error correction algorithm should be used for checking the integrity of the downloaded firmware or at least what's in the box should have pointed it out.

    I am thinking myself out loud here. Honestly, before Sky+ puts out a box, then logically it must have ensured that the operating system is robust enough to self-repair or do a kind of self-diagnostic testing to report and fix failures.

    If this is the case, then logically if the Sky+ box is properly shielded and has effective error correction algorithms for firmware and EPG downloads (not just the EPG firmware updates but the actual EPG datastream), then the problem has to be elsewhere.

    So concluding, I think the probable areas of recording falilures are:

    1. poor electical shielding of the box, susceptible to sunspot activities
    2. no error correction on EPG data download streams (which explains the regularity of the recording faliures every few days)
    3. HDD falilure or incorrectly reported/catalogued bad sectors.
    4. HDD came from a bad production lot (actually if recording failed before, then why didn't the HDD fail entirely? So bad HDD sectors is the likely cause. But then isn't the Planner Re-builder supposed to be recording down bad sectors and do housekeeping???)
    5. built-in self-destruct algorithms ???

    This thread could open up a can of worms or a can of candies.
     
  2. Nick_UK

    Nick_UK
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    Good theory, but unlikely. Because a dish is only "looking" at a very small portion of the sky, and the Sun is only in that position in the sky for a few minutes of each day for about 6 days a year (3 days in Nov, and 3 days in Feb). These are the days when the elevation of the Sun's orbit is the same as the Sky satellites. On these days, at about 1 o'clock in the afternoon, the solar noise picked up by the LNB increases dramatically, because the Sun is aligned directly behind the Astra2 satellites.

    If solar radiation was causing interference to Sky signals, it would affect a lot more than the planner.
     
  3. Eye in the sky

    Eye in the sky
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    Great information! The Sun emits solar flares (Sun spots phenomenon) emit high-power wideband (including C-band, Ka-band and Ku-band) electromagnetic radiations across the solar system in all directions regardless of the earth's position in the sky, even at night. It affects the earth's magnetic fields and all electrical devices. If you look at the chart in the URL, Nov 2004's sun spot activity was indeed the highest.

    In any case, whatever the reasons (my sun spots theory is out of this world I must admit) then all the more important is to have a very good error correction algorithm in the SKY+ OS for firmware updates and other sorts of downloads (I suppose this is one to start with) to make sure the EPG datastream (in our case) is not corrupted by whatever means.

    Being in the mobile handset area of work, whenever we do OTA (Over-The-Air) firmware or service updgrades on handsets, we make sure that the downloaded upgrades is not corrupted. If it is courrupted or the error correction on the phone cannot correct it, a request to resend the firmware will be sent out automatically till the process is completed succesfully.

    The thing is that EPG datastream occurs more regularly than handsets OTA upgrades. And since handset OTA is much crucial for proper functioning of the phone, it has to be more robust than EPG downloads. So maybe the EPG application on the SKY+ may still accept some courruption in its datastream without needing to correct it. It can always wait for a new datastream the next day. The problem will escalate because we already get hundreds, if not thousands, of tv and radio channels on SKY+ or other transponders. The long and short of it is that the SKY+ box must have a good fall-back and error-correction mechanism in case its EPG downloaded datastream is corrupted.

    But I still think HDD corruption in its bad sectors might be the real cause of the recording failures problems experienced by myself or others.

    ###
    Here's a good test!!! For those who have recording failures AND have upgraded their HDDs, could you run a surface test on your original HDD (Maxtor 40GB) to see if there are bad sectors. It would be interesting to get to the bottom of this recording failure business.
    ###
     
  4. Nick_UK

    Nick_UK
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    I don't know if anyone remembers this, but Astra nearly "lost" a satellite a few years ago, because the designers didn't put enough shielding around the gyros, and every time there was a sun spot flare up, the satellite became very unstable in orbit. In the end, they had to have a technician manually over-riding the steering (satellites use tiny gas thrusters to keep themselves in proper orbit), otherwise they were in danger of losing it. I think this was one of the "1" series, which is no longer in commission.
     
  5. alona10

    alona10
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    B4 the days of sky & the 2m Dish/ 1/2 ton of cement in the back garden. My tracker box was wraped in tin foil. will this help. :D

    Alona10
     
  6. GGTVBD

    GGTVBD
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    :suicide:

    Get a life guys.

    A. Dork
     

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