DX Transmissions on 33ft Wire???

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KN4ICU, May 16, 2018 at 3:07 PM.

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  1. KN4ICU

    KN4ICU Ham Member QRZ Page

    Thanks. I am working 40 meters pretty good. Getting contacts regularly 800-900 miles away in the evening with good reports... Sometimes over 1000...Just trying to figure out how to get farther!
     
  2. N2SUB

    N2SUB XML Subscriber QRZ Page

    Are you using a counterpoise on the wire? If not, try attaching a wire to the ground lug of the antenna. The formula for a counterpoise is length in ft = (180/Freq in MHz). You just have to be close, and you can use multiple wires, and route them any way you can, just don't fold one back over itself. This will do wonders for your SWR.
     
  3. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    One big reason you are hearing so well on 20m is that your horizontal (more or less) antenna is close to a half-wavelength high on 20m. This is considered by many to be the minimum acceptable height for a DX antenna - study the patterns to find out why.

    As for 40m, if I am not mistaken, you are spending most of your time around the old Novice band, right? You won't hear much DX there. You will hear most of the DX on the lower 25 KHz of 40m, just like you will on 20m (and all the other "five bands").

    In addition, your antenna is only a quarter-wave high on 40m. You will hear DX significantly less often with a horizontal antenna that is one quarter-wave high as opposed to a half-wave high.

    However, that doesn't mean you can never work DX on 40m with a horizontal antenna about 35' high! I worked my first DX on 40m with a dipole that was one quarter-wave high, and so did many others. So you will occasionally hear DX, just not as often as you would with a horizontal antenna that is one half -wave high, or a vertical antenna. And, lots of times you will hear others working DX you can't hear.

    I hear and work a lot more DX on 40m with my too-low delta loop, fed for vertical polorization and with the apex at 33ft or so, than I ever did with a dipole at the same height. It's not a great antenna, but for DX it's better than a low dipole, at least in my experience.
     
    NH7RO likes this.
  4. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    Raising your antenna higher above ground will certainly help.

    But "most" of the DX on CW is down low in the band, 7.001 to 7.030 or so; you'll also hear DX on SSB (LSB), often between 7.050 and 7.100, where we Americans are not allowed to transmit using phone modes -- but a lot of the world can. If those stations are looking for U.S. contacts, they'll often announce a "listening" frequency, and operate "split" so they can hear us.

    For your operating hours, DX would be mostly to the east, or north/south but not as much to the west. For DX to the west, try very early in the morning (sunrise).
     
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  5. KN4ICU

    KN4ICU Ham Member QRZ Page

    Yes. Using a counterpoise. No problems with SWR whatsoever. Always getting a "flat reading" after tuning.
     
    N2SUB likes this.
  6. W0GSQ

    W0GSQ Ham Member QRZ Page

    Don't wait to upgrade! You have the interest now, do some studying, take the test and see how you do.
     
    NH7RO likes this.
  7. WD0BCT

    WD0BCT Premium Subscriber QRZ Page

    I second this......upgrade when your interest is hot. Sometimes things that are postponed never happen.
     
    W0GSQ and NH7RO like this.
  8. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    Here are the patterns of a dipole at various heights, expressed in terms of wavelenghts. When the dipole is low, most of the radiation goes more or less straight up. For DX, you want the radiation to concentrated at lower angles.

    [​IMG]
     
    KN4ICU likes this.
  9. K4HX

    K4HX Ham Member QRZ Page

    Plenty of DX above 7125. Not much split heard these days other than during contests.

     
  10. KE0EYJ

    KE0EYJ Ham Member QRZ Page

    It's 90% about height and resonance. The rest is controlling losses.

    If you can't build a tower, get a long Spiderbeam fiberglass pole, or something from Maxgain systems. Get your wire up as high as you can -- even if just the center, as an inverted V.

    I lucked-out for a few years, and am living in a house with a flat roof and 5 stories on it. I stuck some antennas about 20 to 40 feet above that, and work 5,000 miles pretty easily, unless bands are not cooperating.

    Not much money, here... just resonant craptennas that are high off of the ground, at the right time of day/night -- all on a 5-story tower that people happen to live in.

    HL1ZIX / KE0EYJ
     
    NH7RO likes this.

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