Any chance this might affect TiVos?

Discussion in 'TiVo Coffee House - TiVo Discussion' started by morac, Jun 24, 2011.

  1. morac

    morac Cat God TCF Club

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    The national power grid is making changes such that the frequency of electricity may be off. This is used in clocks, computers, etc for timing purposes. As such devices can gain or lose time throughout the day. One TiVos adjust their clock daily, but I'm wondering if the changes could cause a time shift and screw up recordings (albeit not by much)?

    http://www.google.com/hostednews/ap...VKugkw?docId=371623ab59694aef9f0a02fe83faca8a
     
  2. dwit

    dwit Active Member

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    "...This won't change the clocks in cellphones, GPS or even on computers, and it won't have anything to do with official U.S. time or Internet time..."
     
  3. morac

    morac Cat God TCF Club

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    I saw that, but then there's this:

    "A yearlong experiment with the nation's electric grid could mess up traffic lights, security systems and some computers -- and make plug-in clocks and appliances like programmable coffeemakers run up to 20 minutes fast."


    BTW the reason it says computers aren't affected is because they set their time via the Internet. So they technically are affected, but they simply correct their time. TiVo does the same, but it is more affected by time discrepancies than a normal computer since it would affect start and stop times.
     
  4. GBL

    GBL covert opiniative

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    Computers run on DC, so no effect.

    Edited to add: What I mean is the actual motherboard runs on DC,supplied by the power supply which converts 110V AC to 12v and 5v DC.
     
  5. dwit

    dwit Active Member

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    That's the way I interpret it also. The Tivo and most home computers have their own internal clocks that are insulated from AC cycles.

    I take it that only devices that are actually synchronized by the AC cycles will be affected.

    Even if a Tivo were not plugged in at all, it would still go on keeping time with it's (coin)battery powered clock like most computers. Of course it is updated to to very precise timing whenever it gets a chance to connect to the mother ship.
     
  6. Worf

    Worf Well-Known Member

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    Yes, only devices that synchronize to the AC line for timing will be affected. These devices are typically clocks (analog or digital, including your alarm clock if it runs off AC). Basically anything that doesn't have a quartz timing circuit to keep time. Things using internet, GPS, or radio ("atomic clock") have internal quartz oscillators that keep time.

    TiVos and other computer-based equipment use their own timing crystals that keep time rather than rely on the AC line frequency to derive timing from. This will include dumb traffic lights (usually driven by a synchronous motor). More advanced traffic lights that are still timing controlled but programmable should be OK as they would have a quartz oscillator.

    For the vast majority of people, the only effect is their wall clocks and alarm clocks will be less accurate. Anything more sophisticated or more modern usually has its own quartz oscillator out of necessity anyhow.
     
  7. lessd

    lessd Well-Known Member

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    And most kitchen appliances that have clocks built in. I just replaced some old alarm clocks with new ones that unknown to me, before my purchase, use the quartz oscillator and battery for time, and AC for the LED display. When you plug them in they allready had the correct EST, and a single button would change time zones. DLS was also automatic, that i liked. (They cost under $20 at Amazon with radio)
     
  8. aaronwt

    aaronwt UHD Addict

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    That's 20 minutes over an entire year. Also assuming that the clock was never set to the correct time. If my clock is off a couple of minutes I will be setting it to the correct time. So in that situation I would need to set the clock several times during that year, each time it was off a couple of minutes.
     
  9. CharlesH

    CharlesH Member

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    Most electronic devices these days seem to have power supplies that are rated for 100-240V at 50-60Hz. Thus they will run just fine in North America and Europe and the rest of the world, given only the correct plug adapter. At least, this is what I have seen on computer laptops, cell phone chargers, and even a newer electric shaver.
     
  10. lessd

    lessd Well-Known Member

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    Computers and most electronics would not have any problem, it just kitchens appliances that would have the most problems as few are 50Hz/60Hz and have clocks. Older alarm clocks and plug in wall clocks will have this problem, but they can be easily replaced. The bigger problem is people knowing about this problem in the first place. TiVos would not have any problem as the clock is run off the battery or DC and does not care about the 60Hz being correct, each call home set the clock so a few seconds per day drift will not be any problem for TiVo, its the TV programs going over the time in the guide that the biggest TiVo time program.
     
  11. ZeoTiVo

    ZeoTiVo I can't explain

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    short answer is
    NO - it will not effect TiVo DVRs time keeping
     

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