TV Aerial resistance

Discussion in 'General Electronics Chat' started by jaffsdad, Sep 23, 2013.

  1. jaffsdad

    Thread Starter New Member

    Sep 23, 2013
    1
    0
    I am on holiday and have new TV and cheap outside aerial.
    Problem ! = no picture. or extremely bad.

    I have checked and remade all connections, and expected "some" ohm's across coax plug at TV end. but its measuring "open" what should I expect please.

    Also I am trying to pick up a boosted and analouge signal, from re-transmitter only 300 yds away..... should I have aerial horizontal or vertical

    Trevor
     
  2. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    5,771
    1,103
    Don't expect much from a cheap aerial at/near ground level.
    Is your aerial a loop or an open dipole type?
    Aerial orientation depends on the transmitter polarisation. Suck it and see.
     
  3. MrChips

    Moderator

    Oct 2, 2009
    12,418
    3,355
    Do TV stations still broadcast analog signals over the airwaves?
     
  4. #12

    Expert

    Nov 30, 2010
    16,250
    6,746
    The carrier is analog, and in the same frequency band as usual, but the information is digital. An antenna on a pole will pick up the signals, and a new TV will interpret them, but an old TV needs a converter box...and they aren't as easy to find as they used to be...which means I will probably drop a perfectly good CRT TV in the trash when my converter box dies. Then I can have something new and modern that will fail and be un-repairable in 4 to 6 years.
     
    PackratKing likes this.
  5. bountyhunter

    Well-Known Member

    Sep 7, 2009
    2,498
    507
    There are tons of DIG converters around, check ebay they cost like $30. I have a house full of TVs using them. You can also use a TIVO box as a converter, I have one of those which I got cheap and use without the TIVO service.
     
  6. wayneh

    Expert

    Sep 9, 2010
    12,089
    3,027
    The OP made no indication that he needs a converter. He asked about his antenna.

    Try an amplified antenna - that's what I use. You can also get a stand-alone amplifier to use an existing antenna. My units receive almost nothing, maybe one channel, without the amp turned on. With the amp on I get channels from the two cities within an hour of my home.
     
  7. #12

    Expert

    Nov 30, 2010
    16,250
    6,746
    At that range you should be able to get a good signal with a twisted coat hanger. Therefore, I don't think this is an antenna problem.
     
  8. vpoko

    Member

    Jan 5, 2012
    258
    47
    If you're measuring the center conductor of your coax on both ends of your coax and getting an open reading, there's an issue with the coax. I don't know for all cables, but for RG-8X coax from Belden, the expected center-conductor DC resistance is 4.3 ohms per 1,000 feet at 20 degrees C. For the outer shield it's 3.3 (see http://www.belden.com/techdatas/english/9258.pdf).
     
  9. w2aew

    Member

    Jan 3, 2012
    219
    64
    Measuring "open" across the coax plug at the TV end is normal.
     
  10. wayneh

    Expert

    Sep 9, 2010
    12,089
    3,027
    Good point. We may never know. The OP seems to be enjoying his holiday by not futzing with a TV. Good choice.
     
    #12 likes this.
Loading...