40 M and I think mine's smaller than it should be...

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by G7VQE, Dec 17, 2009.

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  1. WD5ABC

    WD5ABC Ham Member QRZ Page

    Don't sweat it if you can't do a lot of 1/4 wave radials. If you can't do a few long ones, make a bunch of shorter ones.

    The top-loading might still be doable, just use some twine or something to tie them off once you get the antenna up. When you want to take it down just untie them at the ground and lay it over as normal.

    73,
    Kerry, WD5ABC
     
  2. K4SAV

    K4SAV Ham Member QRZ Page

    It's difficult to see from the pictures but it appears that your radials don't attach at the point where the coax is connected to the vertical. It appears that there is a wire going over to a box on the fence (maybe where the radials are attached). If that is the case, then that wire is your missing antenna length. That wire will be part of the vertical wire. In other words, you have a vertical with a feedpoint attached higher up on the antenna. That's OK but normally that would cause feedline common mode currents, but a choke will take care of that and I see you have a choke. Feeding it higher up on the antenna will also increase the feedpoint impedance, so the fact that you have a low SWR and the resonant frequency is lower than you expected is not surprising.

    Jerry, K4SAV
     
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