Bad capacitors in DirecTV receivers?

Discussion in 'DIRECTV HD DVR/Receiver Discussion' started by merlin50, Jun 29, 2010.

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  1. merlin50

    merlin50 Cool Member

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    Oct 21, 2007
    I am working on my third of fourth failed H20/H21. They have failed 2-3 years after I receive them almost always the same problem start to turn off and on and then just dead. Today NY Times writes of bad electrolytic capacitors in Dell and many other computers and I can't help but wonder if this is plaguing these receivers. DTV is nice always send a new one that works well at first but then they all die no matter the model H21 is no better than H20. I have many older SD receivers in the house no problems. Has this been commented on in this board?
     
  2. davring

    davring Hall Of Fame

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    We can thank our little friends along the banks of the Yangtze river for all kinds of inferior products:)
     
  3. Carl Spock

    Carl Spock Superfly

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    Interesting article in the NY Times.

    I can't say anything about DirecTV's situation, but back around 2004, the time in question here, I heard about a big shortages of capacitors in the audio industry. Some companies ran into problems substituting smaller caps. More often, products were simply unavailable for months, waiting for a crucial part in order to be built.

    It's hard to say what caused your problems, merlin50. Usually if a power supply cap goes, you'll hear it "pop", often see smoke and the piece can smell burned. You don't mention any of those symptoms, but if the cap was elsewhere in the circuit and small enough, you might not notice them.

    It is amazing how tight the supply chain is in electronics. Back around 2000, processing chips became the bottleneck. You generally can't substitute those, so I had pieces for my stereo store on back order for months.

    As we become a more connected society, we also become more dependent upon each other.
     
  4. merlin50

    merlin50 Cool Member

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    Oct 21, 2007
    Some of them pop but others just ooze and go out of tolerance. Heat seems to be a big issues in these failures and many of mine are in enclosed cabinets that probably contributes to their failure although one of them was in the open. I have surge protectors on them but who knows maybe the suppressors have bad components. The weakness in the supply chain are shocking and I guess we get what we pay for as most components are bought at cut rate prices to compete on price.
     
  5. BattleZone

    BattleZone Hall Of Fame

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    Keep in mind that the LG-manufactured H20-600 had an under-rated power supply, which caused those units to run very hot and fail early. That's fairly unique among DirecTV receivers, though.
     
  6. videojanitor

    videojanitor DBSTalk Club Member

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    Probably not the same thing, but it seems pretty clear the build quality of mainstream consumer electronics just isn't that great. I'm sure corners are cut wherever possible. Instead of "over-building" circuits, they are "under-built" -- running too hot, which will almost certainly lead to premature failure. Electronics do not like heat.

    It's amazing how short the life-span is for some of this stuff. Just last week, I had to get a new DSL modem as the old one konked out. The guy at the AT&T store said "yeah, they only last about three years." Three years?? That's a pretty poor design. I have audio equipment from the '70s that still works great. You would think the large electrolytic capacitors in the power supplies of some of these audio amps would have dried up a long time ago, but they're still holding a charge just fine. Barring a catastrophic failure, a well-designed piece of electronics should last for decades.
     
  7. Jul 1, 2010 #7 of 49
    Lee L

    Lee L Hall Of Fame

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  8. Jul 1, 2010 #8 of 49
    Mrmiami

    Mrmiami Legend

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    Well Dell PC's and especially their laptops had/have a terrible reputation for their fans not turning on, not turning fast enough or long enough and that equals toast for those caps. I went though 2 of their laptops in a 2 year span turns out the Smartstep was a Dumbstep for me, worst part was, they wouldn't acknowledge they had a defect and squashed all of the support topics about it so you couldn't see just how widespread the problem was or get help with it b/c 8 months after it's release replacement parts were no longer being made for it. Me thinks they knew they had a stinker there and didn't feel like they owed anyone-anything for their average 2K investment. No more Dells in this house.
     
  9. Jul 2, 2010 #9 of 49
    TomCat

    TomCat Broadcast Engineer

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    I had a HR20-700 that I got in March of 2009. It gradually began to stutter the video on playback which could be fixed by a reboot for a number of days. Eventually the fix time grew shorter, and by January of 2010 it started rebooting spontaneously. Ever curious, I popped the hood before I sent it back after getting a replacement, and the two large filter caps on the PS were both domed and bulging.

    From this I concluded that ever increasing ripple in the DC was what might be causing these problems. Heat dries out caps, and their values change, and in a PS that means dirty power, which microprocessors abhor. And this is dirty DC, after any AC UPS, and a UPS can not help matters in such a case (other than to prevent surges, which can also damage caps).

    But I am careful to keep DVRs and the like well ventilated, and I even put a $9 Walmart clip-on fan on the back of each DVR (and my AVR as well). But then this is the desert, and summer temps get to 90 inside when you are not there unless you are wasting power to keep the place cool when you are gone, so maybe that was a contribution. But then I have had 14 different DVRs since 1998, and this is the only case I have had of a heat-related or cap-related failure.

    One of the issues is that caps should be 105-degree caps if they are meant to be in a hot enclosure. Many caps are only 85-degree caps. Sometimes when they run out of 105's they might put in 85's just to keep the assembly line moving. The caps in my '20-700 were 85's.

    Bottom line, use fans and good ventilation, and if you have symptoms such as I had, failing PS caps could be the reason.
     
  10. videojanitor

    videojanitor DBSTalk Club Member

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    I'm surprised you took the risk in opening the case before you sent it back -- not sure what happens when they see the seal has been broken.

    Using a fan sure does make a difference, especially on the HR20. The internal temp on mine averages a "cool" 106 with a fan sitting on top.
     
  11. kevinturcotte

    kevinturcotte Active Member

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    Outside...
    They don't seem to like to make things that can withstand "Extreme" temps. I remember some of the earlier SWM LNBs couldn't handle temps below freezing. Come to Maine in the winter lol It will probably get below 0 lol
     
  12. bubbagscotch

    bubbagscotch AllStar

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    Oct 31, 2009
    I got this from a drd435rh review on the amazon's website definite capacitor failure:

    "I got this unit to use with DirecTV in 2002. It performed very well. Occasionally, it crashed, and had to be unplugged for a few seconds to be reset. This happened only every few months, so it wasn't a big deal. Sometimes the box responded slowly to the remote, but it fixed itself after a few hours. The menu operation was close to perfect. I liked this practically trouble-free thing, until February 3, 2010.

    That morning, I was in the office and heard what sounded like an M80 firecracker in the living room. The dog ran into the hallway in a panic. I went to see what made the noise. Smoke was pouring out of the DRD435RH receiver. The room was filled with it and it smelled really weird. I unplugged the very hot box, unhooked the cables and tossed it outside. I suspected a voltage hit, but nothing else was damaged. VCR, DVD, digital converter box, DVR, TV sets, computers, everything was fine. The UPS didn't beep or show anything wrong. The receiver simply chose that moment to explosively die. I looked inside and it was black and melted in places. It may have started a fire if I didn't work at home. As it is, the failure was mildly inconvenient and DirecTV is sending a new box. "
     
  13. TomCat

    TomCat Broadcast Engineer

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    Well, it reminds me of the time I was fixing an old video monitor (at the time, it might have even been older than I was). I had just replaced a very large cap, yet I had no video at all (before at least I had rolling video). Confused by this I put my face very close to the circuit board, still plugged in to power. For about 20 seconds I hovered there, but everything seemed normal, so I pulled back up to a seated position. Not 5 seconds later, BLAMMO!, the cap exploded all over everything. But then there was a very good reason for that, which is that electrolytics are typically polarized, and I had put the cap in backwards (reversed polarity). The rest of the guys in my shop had a good laugh at that, and it took a couple of years to live that one down. Some guys still called me "Sparky" years later.
     
  14. TomCat

    TomCat Broadcast Engineer

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    Aug 31, 2002
    Well, they've had 6 months to complain, and I never heard a peep, so I guess now we know what happens. But then the sticker was only affixed to the lid, not the chassis as well.

    But then I think they are not motivated to be hall monitors and force good customers to follow the spirit and the letter of their agreements simply on principle. In a perfect world they would like to do that, but the world is far from perfect. Other factors trump a little under-hood foolin' around. IOW, they have little to gain by scolding me for opening the case. Sure, they want to discourage that, but they won't risk that $112 a month I send them just on principle. Now if I had eaten a pizza in there and dripped special sauce over everything, that's different. But swapping a HDD or two, no problem, as long as it goes back in the shape you got if from them.
     
  15. videojanitor

    videojanitor DBSTalk Club Member

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    Oct 8, 2006
    HA! I can see it now ... the DVR arrives back and cheese is oozing from the vents ...

    I have no doubt you are correct ... we all know that we're not supposed to monkey around inside these things, and there are plenty of warnings in this forum against that, but I have yet to hear anyone say they got dinged for it (which isn't to say it COULDN'T happen). Interesting that your sticker was only on the lid -- on both of my HR20s, it spans the chassis and the lid, making removal obvious.
     
  16. hdtvfan0001

    hdtvfan0001 Well-Known Member

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    Jul 28, 2004
    Like PC's...power supply issues can play havoc with HD DVR performance and results.

    Having seen a number of units inside over the years...the more recent ones seem to have some pretty solid power supplies.

    The HR20's have been workhorses, but yes...some of those may be showing signs of their "age".
     
  17. ndole

    ndole Problem Solver

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    I've always wondered about UL's position on that box. It is in fact UL listed. But I could envision the right criteria where it could cause a house fire ;)
     
  18. TomCat

    TomCat Broadcast Engineer

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    Well, The UL is probably about as affective as the Minerals Management Service. Bureacrats sitting around downloading porn and playing solitaire.
     
  19. bubbagscotch

    bubbagscotch AllStar

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    Oct 31, 2009
    That must have been hilarious. I can just picture you relaxing and all of a sudden kaboooooooooooooooooom! I can see why they call you sparky. Don't try that again unless you check those polarities on the capacitors.
     
  20. netraa

    netraa Godfather

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    My very expensive samsung tv has been bit by the bad caps bug. TV was made a LNT4665 circa 2008

    I had to take the thing apart, unsolder 6 caps from the power board, and replace them with beefier caps.

    The wife had a total COW when she walked in on the operation and I had the patient on the bed, with the back off, circuit boards lying on the pillows and tupperwares all over with different sized screws in them.

    Tv is working great now 1+ year on.
     

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