Help newbie 1974 FJ40 coax cable antenna

Discussion in 'Communication & Navigation' started by BlueMarblePA, Nov 29, 2018.

  1. BlueMarblePA

    BlueMarblePA

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    So I just bought a 1974 FJ40 which has a 4 plus swing out bumper and a coaxial cable wired up for cb antenna

    My brother gave me his galaxy dx 959 with mic. I bought a simple cigarette lighter adapter and am excited to connect.

    The antenna mount looked strange and I think I buggered it up so I reconnected. See pictures below.

    This seemed to work as I turned on the cb and got static until I got to channel 6 and was able to hear some chatter.

    Now when I go to channel one and 40, and check the swr meter, I am above 3. Indeed in every channel, the swr meter alert led turns on.

    Obviously I was testing in my closed garage as it is cold here in Philadelphia, but I am encouraged because at least I heard something.

    Is my setup going to work, or do I definitely have to do some tuning of antenna?

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  2. BlueMarblePA

    BlueMarblePA

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    Final picture of assembled antenna

    20181129_163115.jpg
     
  3. BlueMarblePA

    BlueMarblePA

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    Okay. I just read that testing inside a garage is a big no-no. Will have to test outside in a clear field.
     
  4. 1911

    1911 chupacabra

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    I have my cb and 2 Meter ham antennas on my 4Plus bumper also. There is not much ground plane back there, so a 1/2-wave antenna will tune up a lot easier and give better SWR than a 5/8-wave or 1/4-wave antenna.

    I didn't trust the swing-outs to have a good ground with the frame, because of the greased bronze bushings on the pivot pins, so I ran a braided stainless steel ground strap from the antenna mount to a bolt in the tub (long enough for the basket to swing out). If you don't have a good electrical ground for the antenna, you will get very high SWR.
     
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  5. BlueMarblePA

    BlueMarblePA

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    @1911 this is really useful information. I think I want to do the same which is run cb and ham but start with cb first.

    I tried looking for a 1/2 wave antenna but am confused. Can you direct me to one? I found the firestik no ground plane antenna. Is this the same?

    I will have to check where the ground goes to. As can be seen in the photo, there is a ground from the screw for the antenna mount down the cord. Since this is an aluminum tub, I will have to verify that this goes down to the frame.
     
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  6. 1911

    1911 chupacabra

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    Yes; any "no ground plane" antenna is by definition 1/2-wave. I think mine is a Wilson, but it's been long enough that I don't really remember or have any literature from it. I could take a photo of mine if you want.


    That would be best. Envious of your aluminum tub though!
     
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