Help with cablevison ground loop problem?

Discussion in 'Beginners, General Questions' started by Mike Milillo, Apr 22, 2004.

  1. Mike Milillo

    Mike Milillo Stunt Coordinator

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    Hey guys. I tried hooking up a sirius plug and play audiovox unit to my AV receiver. It wouldn't work and after much phone support and messing around we discovered that when the cable box is disconnected from the AV receiver the plug and play works. The unit connects to the receiver with an RCA left/right on one end and a mini headphone type jack on the audiovox end. The tech from audiovox told me that this does happen occassionally when you are having ground loop problems from the cable company. He said there is some device that can be placed on the line which will clear it up. I can't get through to them tonight, but does anybody know of what he speaks of? I would greatly appreciate any help you guys can point in my direction. I assume it is some type of filter, thanks in advance guys
     
  2. Chu Gai

    Chu Gai Lead Actor

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  3. Mike Milillo

    Mike Milillo Stunt Coordinator

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    thanks, but will this interfere with my digital cable in any way? I run digital coax and RCA's, and s-video from my cable box to the receiver
     
  4. Bob McElfresh

    Bob McElfresh Producer

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    It should not interfear.

    You really dont have a ground-loop. You have 60 hz noise.

    The CATV coax running for hundreds of yards outside your home and it acts like an antenna. It probably runs near some power wires and the shield picks up a small amount of 60 hz noise.

    The shield of your CATV coax now connects to the 0.00 volt reference of your electronics. This 'contaminates' what should be 0.00 volts with 60 hz signal.

    The Isolation transformer is a filter. It stops signals below some value from traveling from the input to the output. But it lets any higher-frequency signals pass through with no problems.

    All your digital signals are fairly high-frequency and should pass through fine.

    You do have some alternatives:


    - Call your CATV company for a service call. They will come out and install a "Ground Block" that takes the shield of the CATV coax and ties it to electrical or earth ground. Or, they will ground the CATV coax somewhere up the line, or give you a isolation-filter.

    - Buy a surge-supressing power strip with the "F" connectors and run your main CATV coax through this. The power strip will act like a grounding block. (Note: you MUST have the power strip plugged into a grounded electrical outlet for this to work.)
     
  5. Mike Milillo

    Mike Milillo Stunt Coordinator

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    cool, thanks for your help guys
     
  6. Chu Gai

    Chu Gai Lead Actor

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    If you remember, post back with what you did and what your results were. Helps all of us at HTF [​IMG]
     
  7. Mike Milillo

    Mike Milillo Stunt Coordinator

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    Ok, I found a good fix for the problem. I went to radio shack and picked up loop ground isolator. I placed it between the Audiovox unit and the AV receiver and the problem went away. Thanks for your help guys, much appreciated.

    http://www.radioshack.com/product.as...t%5Fid=270-054
     

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