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Over the air tv interference

Discussion in 'General CB Services Discussion' started by 455monte, May 5, 2021.

  1. sp5it

    sp5it Master of puppets

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    Check it, because if your antenna is in different polarity than transmitter antenna signal loss is huge. In my country in some areas it is vertical, other areas horizontal polarization.


     
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  2. snippits75

    snippits75 Well-Known Member

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    https://wiki.radioreference.com/index.php/Television_Frequencies

    Look at the frequency chart I linked above. The filter I mentioned earlier passes the TV frequencies, and filters below that which will include the CB band.

    I had an Antron splatter stick about 15 feet away from the TV antenna. Four watt radio would cause squiggly lines on the TV. Amp on and there was no picture. Filter fixed my problem.
     
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  3. 455monte

    455monte Active Member

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    Snippits, i ordered a similar filter from amazon a few days ago.
    It does same function as one u posted. It should be here tomorrow and i will give it a shot.

    Mike my current tv transmitters i receive range from 16 miles to 65 miles away
     
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  4. Rwb

    Rwb Sr. Member

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    i believe we are on same page on his tv. weak signal n a low watt radio over rides tv reception . filters wont help either. but bad tv coax can contribute as well as connections
     
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  5. 455monte

    455monte Active Member

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    Last night i moved the sirio to the back corner of my shop. This is 25 feet further away from the tv antenna. Now i can talk barefoot without tv interference .
    Still cant transmit using the rm 503hd without upsetting the tv.
     
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  6. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    What happened to the 3rd ground plane rod?
     
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  7. 455monte

    455monte Active Member

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    I have the 3rd rod. I have my antenna mountwd on a counter lever bracket i made so that when storms are coming i can pull a string and the antenna lays down on the shop roof.
    With only 2 ground plane rods it is shaped like a T
    If i added 3rd when it kayed down i would have a 51 inch rod sticking straight up.
    What does using or not using the ground plane rods accomplish?
     
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  8. jdchet

    jdchet Supporting Member

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    This might be of some help............
    https://www.antennasdirect.com/transmitter-locator.html

    JD
     
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  9. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    I think the ground plane rods mostly effect the radiation pattern and maybe the SWR. I was thinking along the lines of common mode currents and was wondering if this was the cause of your problem? Do you still have the problem with all of them installed?
     
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  10. M0GVZ

    M0GVZ Sr. Member

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    How old is the TV antenna coax? It typically has a lifespan of around a decade but here in the UK it's not uncommon for houses to have cable that's 20-30 years old and the first people know of an issue is when water is coming out of the cable at the TV end.
     
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  11. Shockwave

    Shockwave Sr. Member

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    Install the third ground radial. It's not optional and without it your coax could be radiating interference.
     
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  12. 455monte

    455monte Active Member

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    Okay guys check this out.
    I changed the cheap gas station rg8x coax out for a expensive lmr400 and added the 3rd radial to the base. 99 percent of the interference went away on 1 of my tvs. Ironically the tv antenna furthest away from the cb sirio antenna still recieved interference. (The 2 week old one)
    So i reconnected the original tv antennna to that tv and problem solved on am using the 503hd
    On lsb with 503hd theres a minimal interference on a few tv channels. I assume those are the weak channels.
    On a side note the tv coax hi pass filter didnt help at all
     
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  13. S&W357

    S&W357 $upporting Member N.C. WDX-556

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    I’m guessing you’ve checked TV coax connections and they are tight?
     
  14. 455monte

    455monte Active Member

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    Yep
    All were tight on the 2 week old tv antenna and amplifier.
    I think it was prob the onn brand amplifier receiving interference on the new attic tv antenna.
     
  15. 455monte

    455monte Active Member

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    I will do some further testing tonight.
    Hopefully there will be some skip to enjoy
     

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