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

HD DVR Coax Routing

Discussion in 'DIRECTV HD DVR/Receiver Discussion' started by 1953, Mar 8, 2012.

  1. jimmie57

    jimmie57 Hall Of Fame

    6,628
    319
    Jun 26, 2010
    Texas City, TX
    Your information is very interesting. I think I will have my electrician that I use come and inspect my ground and advise if it is good or he needs to do it differently.
    I have a beautiful picture now for almost 3 years with zero problems so I do not believe I am getting noise the the cables.
     
  2. CCarncross

    CCarncross Hall Of Fame

    7,058
    60
    Jul 19, 2005
    Jackson
    I never recommend routing your sat coax line through the coax jacks on a surge protection device....unless they are rated for the full rated FR(up to 3GHz or so), and are known to pass power(DC voltage is critical to correct functionality), they should not be used...UPS/surge protectors are fine for the power, just not the coax runs...
     
  3. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

    42,679
    348
    Dec 9, 2006
    This whole thing is fairly complex, so it's no wonder not all of this is obvious.

    The SAT signal has a few aspect to it:
    1) the RF power level, which can only be measured with a power meter.
    2) this same meter measures carrier to noise [the good from the bad in the signal].
    The bit-error rate is directly related to the CNR, and only when the RF power drops so far that the CNR drops, will you "see" a change on the SAT setup screen.
    The more RF power to start with, the more "system reserve" you have for rainfade resistance.

    I don't know the circuits in the Monster unit, but it can basically only do one of two things:
    1) it is set to filter AC [110] voltage, which isn't on the coax from the dish, so it does nothing.
    2) it's filtering minor variations on the coax, which is what is coming from the dish as "good signal", so the digital demodulation is being adversely effected to some degree.

    Monster is selling these, so of course they're going to be biased and never tell you they aren't going to do anything for your system [DUH].

    Should this be connected to a coax off the utility poles, it would have a use, but from a dish is pointless.

    When you call your electrician, if he's a good one, he'll see what's going on. If he's "not so versed", he may treat it like all AC [house wiring this time] and tell you "a ground is a ground" and it's good enough. All house wiring has the grounds daisy-chained, so he may not see why the AC unit's ground isn't the best solution.
    A more versed one who understand low voltages signals, should.
     
  4. hasan

    hasan Well-Known Member

    5,957
    54
    Sep 22, 2006
    Ogden, IA
    "The bit-error rate is directly related to the CNR, and only when the RF power drops so far that the CNR drops, will you "see" a change on the SAT setup screen."

    I think you meant to say "is NOT directly related to the CNR"...at least not until the CNR degrades to the point that it affects the BER.

    Simple typo, (I think), and I got what you meant...and it was very well done.
     
  5. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

    42,679
    348
    Dec 9, 2006
    Maybe I should have worded it:
    the bit-error rate is directly related to a good CNR. As the CNR degrades, so does the bit-error rate degrade.
     
  6. 1953

    1953 Icon

    738
    7
    Feb 7, 2006
    Desoto, TX
    Well here I am, a new owner of a Panamax M4300-PM. Honestly, I cannot begin to join in your technical discussions due to my lack of knowledge so I'll speak from a plain Joe's point of view

    All I can say is that during the years we used a Monster HT3600 MKII this device protected our AV equipment during many, many voltage spikes, surges, lighting strike and power outages. With the HT3600's demise I researched the devices on the market along with opinions from three forums. After feeling my head was about to explode I came to the conclusion that about 50% of those who offered advice preferred not to use power centers. Many surprised me by supporting UPS's with the minority liking power centers.

    I was ready to go the high quality surge surpressor route until my wife reminded me how well the power center performed and (now don't throw rocks at me) to some degree improved both the audio and video. There is no way I can support my position other than tell you visitors to our home were and still are astounded by the our systems performance.

    The new Panamax M4300-PM is installed, coax, telephone line included. I was surprised by the strict warranty conditions but that will be presented in a new thread. Please accept my sincere appreciation.

    Louis
     
  7. ndole

    ndole Problem Solver

    1,915
    5
    Aug 26, 2009
    People sometimes (far too often) tell me that they have better PQ after I dither their ODU (to pass Installation Verification) :rolleyes:
     
  8. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

    42,679
    348
    Dec 9, 2006
    So the picture "pops" after a dither? !rolling
     
  9. netraa

    netraa Godfather

    483
    0
    Mar 27, 2007
    Just like they swear they get a better picture out of the $160.00 monster HDMI cable that's so thick and heavy it's going to stress and break the internals of the HDMI ports.
     
  10. TomCat

    TomCat Broadcast Engineer

    4,153
    100
    Aug 31, 2002
    Jimmie, if you have a surge suppressor, use it. It has some value. But DTV is probably correct that it may not pass the L-band frequencies that DBS uses, especially for SWM where some frequencies are converted to a higher band. Rolloff from that connection is just as bad as a misaligned dish in many circumstances. So, use it for a surge suppressor, but patch around it for the L-band distribution from the dish. That connection is of questionable worth even for cable or antenna, but pretty useless if not detrimental for L-band.

    I find all of this talk about "static" discharge a little disturbing. L-band distribution is a closed system and is essentially a waveguide, meaning that it would be highly unlikely for a charge to build up anywhere with a current level capacity that could cause any sort of problem, wind or no wind. If you have enough wind to generate that much current, you have much more serious problems and should head for the corner of your basement.

    The DBS distribution system is DC voltage one direction and RF the other, has no connection whatsoever to AC power, and even if there were a static discharge of any size, that could not likely have any affect on such a system. You would have to have someone at the dish cranking on an attached Wimhurst machine before the current levels could be of any level that matters.

    Speaking as an RF Engineer for cable and broadcast for over 3 decades, I have seen a lot of weird things, but none of them were ever attributable to static discharge, which is mostly a term co-opted by Monster to put the seed of doubt and fear in your head to get you to buy their crap.

    Usually the problem is a difference in ground potential between cable TV (which gets its ground elsewhere) and the house (which gets its ground from the power company). If the power company ground at your house is bad enough, the lights can actually go off when the cable TV gets disconnected! I've seen that first person (house ground lost, so electrics in the house use the cable sheath as a path to ground. Cut the cable TV off, and no ground, no power). I've also seen cable melt overnight at the ground block because of a few volts difference between grounds, which makes the DC loop resistance of a cable drop essentially a resistor in a closed circuit and creates enough heat to do that.

    But a DBS install gets it ground, if it even has one, from essentially the same ground as your house's power company ground. Unless you have severe wiring issues, the ground for all circuits should be about the same. And even if they are not the same, a small difference will not affect a DBS distribution system.

    I'm afraid that assuming static discharge as the culprit for frying DVRs is nothing more than wild uneducated speculation. A much more likely culprit would be a power surge (and not through the distribution system, but the house AC) or a nearby lightning strike, which essentially can do the same thing (weather was clear; rule that out in this case).

    Grounds, good or bad, do not generate surges or static discharges. A bad ground can never be the cause of such a problem, but it can certainly contribute to the system not being able to survive such a problem without damage. That is what the ground is for; to limit potential damage when unwanted current gets induced into the system.
     
  11. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

    42,679
    348
    Dec 9, 2006
    Tom, this was a good post and it's clear what experience and understanding of the issues does.
    I hate letter band designations, as they vary by which group you're in [bats verses crows, etc.], so I had to google L-band.
    The only change to your post has to do with the part I quoted.
    "non SWiM" uses 3 500 MHz blocks: 250-750, 950-1450, 1650-2150 MHz.
    SWiM uses 974-1790 MHz.
    "So" it actually is using less of the higher frequencies, and only crosses over 1450 MHz when 5 tuners are connected.
     
  12. CurtP

    CurtP AllStar

    75
    1
    Jan 8, 2008
    The Monster power centers are nothing more than a glorified UL1449 surge suppressor with the typical Monster price tag. I made the mistake of cracking mine open only to discover how cheaply they're built. I've since replaced them with real power conditioners. I'll never spend another dime on any of their products. Monster=junk.
     
  13. allenn

    allenn Icon

    704
    0
    Nov 19, 2005
    Georgia
    Me too! I had a $80 Monster HDMI cable go bad. I replaced it with the D* HDMI cable ($10 at most) which came in an HD connection kit years ago. Yes, Monster replaced the cable, but I have no reason to swap out the D* cable.

    Best wishes!
     
  14. 1953

    1953 Icon

    738
    7
    Feb 7, 2006
    Desoto, TX
    That's probably why they do not repair them. My new Panamax was highly recommended.
     
  15. jimmie57

    jimmie57 Hall Of Fame

    6,628
    319
    Jun 26, 2010
    Texas City, TX
    I have the HDP2400 model. I got them New on Ebay for $129 each including the tax and shipping.
    They work for me.
     
  16. ndole

    ndole Problem Solver

    1,915
    5
    Aug 26, 2009
    Not only does it pop, it pops and locks it down (apparently) ;)
     
  17. TomCat

    TomCat Broadcast Engineer

    4,153
    100
    Aug 31, 2002
    But you got the generic description for L-band, not the conventional one for sat and DBS, which typically (until BB converters) never seriously used 250-750, and (until SWM) never really used 1650-2150. Not that this answer is not correct, it is. But it is so "correct" as to be almost too comprehensive, as my description of L-band was based on what is used commonly in DBS and the professional geosat industry.

    I have engineered thousands of sat uplink sessions and countless downlink sessions in my professional capacity over the years, and never have any of the downlink sessions ever used anything but the conventional 950-1450 L-band, so I guess that makes me a victim of being too close to common usage and not comprehensive enough to cover the rare or odd uses of L-band as well. Sorry about that. But your input is always appreciated.

    What should the reader take away from this? That all devices used in L-band distribution for DBS should now be rated or swept to 2150 to avoid rolloff of those higher frequencies. Since surge protectors are typically rated for OTA antenna, they may start rolling off as low as 890, maybe even lower. That will "fade" your reception pretty quickly for higher channels.
     
  18. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

    42,679
    348
    Dec 9, 2006
    That a few of us, know way more than we should. :lol:
    Didn't I mention I don't care for letter designations?
    [not picking on you at all]
    "Generic, Conventional, used Commonly in DBS and the professional geosat industry"
    Well frankly we should be using what DirecTV does in this forum, but like I said, it's which group you're from that defines what each of us are used to calling what.
    I'm an old crow, so we always use different letters than "the other guys".
     
  19. carl6

    carl6 Moderator Staff Member DBSTalk Club

    12,436
    929
    Nov 15, 2005
    Seattle, WA
    Yeah, they changed the alphabet sometime back in ancient Roman times :lol:
     
  20. veryoldschool

    veryoldschool Lifetime Achiever Staff Member Super Moderator DBSTalk Club

    42,679
    348
    Dec 9, 2006
    http://www.crows.org/


    [YOUTUBE]mDirzDOjysM[/YOUTUBE]
     

Share This Page