Signal loss over coax. Solution?

Discussion in 'Free To Air (FTA) Discussion' started by oldsmobile, Oct 9, 2019.

  1. oldsmobile

    oldsmobile Topic Starter SatelliteGuys Family

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    Hi, folks.
    Well, I've been working on the dish farm a little bit. I have a 90cm on the roof, and it's for 87 & 91. To date, I only had the 87 tuned in, since I didn't get the time to dedicate to the dual LNB. I'm using a Geosatpro 4 degree kit, and the matching bullet LNBs with two outputs.

    On the roof, I have a lock on the signals, and it is as close to the sweet spot as I can get.
    LPB comes in at 7.7dB
    CNN comes in at 6.0dB
    I'm using one of the ebay ~$40 Satlink WS-6933 meters, and Q is around 29% - 33% (fluctuates a bit) on each of these TPs.

    However, something changes by the time it gets down to the basement where my switch is.

    After the run through ~40 feet of coax, CNN has dropped to 4.7dB. My X2 receiver can't lock it in, and gives the Q at 20%.

    LPB in the basement still locks in fine at 6.0dB.

    These are numbers straight off the coax, and not running through my Pansat 8x1 switch.

    This suggests to me that there is a loss in the coax, and I know that over long runs, loss can be significant. But I wouldn't expect it to be that big over just 40 feet or so.

    Coax is Tappan dual shield RG-6. It tests fine (no shorts) on my coax tracker.

    I have a couple of thoughts:
    1) Not enough signal here for sharing 87 & 91 on a single dish with these LNBs?
    2) Interference in the wall run with multiple cables?
    3) Would quad-shield coax help this situation? I would rather not pull new coax, but I can do it if it is going to improve things.

    I appreciate any suggestions!


    This is my meter here: Satlink WS-6933 DVB-S DVB-S2 FTA C&KU Band Digital Satellite Signal Finder Meter 690002124813 | eBay



    This is my coax tracker here: 8 Way Coax Cable Locator Mapper Toner Tracer Finder Identifier Tool RG6 Vericom | eBay
     
  2. harshness

    harshness SatelliteGuys Master

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    40 feet is not a great distance. >120 feet is a great distance.

    I expect that either your connectors are booged or you have some really lousy cable.

    It looks like the cable might be copper clad steel (CCS) rather than solid copper core so there may be some DC power loss going on that is starving your LNA.

    The signal loss is kind of in the middle of the range (assuming I've guessed correctly about which part number you have).
     
  3. oldsmobile

    oldsmobile Topic Starter SatelliteGuys Family

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    Yes -- it is marked as CCS. I never noticed that before. I have lots of it in use, but this is the only one that has given me any problem. Longest run would still be less than about 50 feet.

    I'll put new ends on what is already there, and see if that makes a difference. If not, I guess I'm buying some better coax for this run, anyway. Thanks for the input!
     
  4. tdti1

    tdti1 SatelliteGuys Pro

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    What brand cable is it? I usually recommend rg-6 solid copper core up to like 80' or so, on longer runs just go with rg-11. What connectors are you using? I use PPC compression connectors.

    Not sure if you have interference problems? Maybe some quad? I've never had to use quad personally.
     
  5. oldsmobile

    oldsmobile Topic Starter SatelliteGuys Family

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    Cable is Tappan, which I'd bought at Home Depot. Last night I put a new end (I don't know what brand--Ideal, maybe?) on the basement end of the cable, but it made no difference. I will try to get back up to the roof tonight and do a new end up there.

    I'm trying to reconfigure the farm a bit. I realized that there is nothing on 97 I want to watch, and there hasn't been anything there for a long time. If I can consolidate a bit, it'll improve the general appearance of the place. :)
     
  6. oldsmobile

    oldsmobile Topic Starter SatelliteGuys Family

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    Sigh. I got home early today and decided to redo the connector up on the roof. I did fine adjustment too while I was up there, getting 6.9 dB on 87 and 6.0dB on 91.
    Went downstairs and there is zero Q and no lock. Which is worse than last night. Sigh. Either I screwed up the end, or this coax is no good.
     
  7. oldsmobile

    oldsmobile Topic Starter SatelliteGuys Family

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    Whoo-hoo!

    Went back up, redid the cable, and found a sweeter spot to aim that I just couldn't find before. 91 at 9.0dB, and 87 at 6.9db. I am happy!

    I'd had a dedicated 76 cm for just 91, and I think that can have a new purpose.
     
    FTA4PA likes this.
  8. tdti1

    tdti1 SatelliteGuys Pro

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