Radials with trap vertical

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by WB3CQA, Oct 9, 2019.

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  1. KA0HCP

    KA0HCP XML Subscriber QRZ Page

    The hard part is keeping the tomatoes green in January! ;)
    AK5B likes this.
  2. WA4SIX

    WA4SIX Ham Member QRZ Page

    I laid a bunch of this fencing for my 6BTV. Worked great.
    Moving to Florida in a couple weeks & will lay 2-100' lengths of it in an "X" pattern, along with some wire in the middle for the 6BTV.

    AK5B likes this.
  3. WB3CQA

    WB3CQA Ham Member QRZ Page

    Thanks to all for quick and very helpful replies! I now have a project to get done before winter.
    AK5B likes this.
  4. N8CMQ

    N8CMQ XML Subscriber QRZ Page

    I am running a similar antenna, but my radial field is extensive.

    I watched the receive signal strength go up, but nothing drastic as I worked on adding radials,
    however, the noise went down as I added radials.
    The transmit signal strength also seemed to improve as I added radials, again, nothing drastic,
    and I didn't do an A, B, C, comparison on any of the testing.

    With the radial field being so large, I figure the ground losses are reduced in the near field,
    and the common mode noise has a better blocking effect with it.
  5. K8JD

    K8JD Ham Member QRZ Page

    My Verticals
    BEST performing verticals I ever had (for DX results) were QW verticals roof mounted, one on the garage roof for 20 M with 4 1/4 wave +5% radials, and another on the house roof for 40 M. with three radials, 1/4 wave +5%.
    I worked ZL from Detroit for the 2nd QSO on the night I got the 40 M GP up and tuned. Running 100 W/ !
    I worked my first VK on 20 M SSB the next night on 20 M.
    Last edited: Oct 11, 2019
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  6. AI3V

    AI3V Ham Member QRZ Page


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  7. WA7ARK

    WA7ARK Ham Member QRZ Page

    Results entirely consistent with simulation!

    Some OFs refuse to believe that there is such a thing as Common Mode Current that makes the coax shield an active part of an antenna. (They are wrong!)

    They also refuse to believe that a Marconi has significant CM on its coax, especially if the coax comes radially away from the base of the vertical, parallel to one of the "radials". (They are wrong!)

    They further refuse to believe that if the driven end of coax run is in a RF noisy environment, that can overcome the otherwise excellent shielding effect of the coax itself by conducting the RFI toward the antenna, where it flows onto the driven element (vertical) thereby creating a voltage at the feed-point which then becomes a differential signal that travels inside the coax toward the receiver. (They are wrong!)

    They further refuse to believe that effective blocking of CM (which stops CM current flow in either direction) is as simple as wrapping 8 to 15 turns of Teflon coax through the hole of a $7 ferrite toroid. (They are wrong!)
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  8. F8BDX

    F8BDX Ham Member QRZ Page

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  9. KF5LJW

    KF5LJW Ham Member QRZ Page

    That is not likely going to change much. Most likely those that you hear clearly and having trouble copying you are running much higher TX wattage than 100 watts. If they run legal limit are transmuting almost +12 dbm higher power levels. In ham or layman terms is 15 times more power than you. On paper 4 times the distance than you.

    Most likely what you are going to notice is somewhat improved operation as you add radials. But do not fall for more the better. You will hit a point of diminishing returns. You will not notice any improvement after a certain point.

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