Using a fence as an antenna

I always wanted to try something other than an antenna as an antenna, so I decided to try to join our clubs topband net, whilst out portable and using a wire fence. I spent the morning modifying my MFJ-971 portable tuner, by adding an extra inductor in the form of a T130-2 torroid, with 29 turns, in series with the main inductor inside. This is only in circuit when the tuner is in the highest inductance setting, where it will use the whole wire inductor and my torroid. MFJ say this tuner is for 1.8-30MHz, but its really 3-30MHz, unless youre tuning a 50Ω load! It now works nicely with most things on 1.8MHz.

So, over to the country park I went, set up this tiny station, clipped my feed to the top piece of galvanised wire, and my ground to the lowest piece, and the mesh. To my surprise, it tuned easily, and worked ok to the local contacts. This fence is 1 metre high, and around 150 metres long. Now, i’m wondering what I can use next! John.

FT-817ND and Tuner

The general setup

The general setup

Here is the feedpoint!

Here is the feedpoint!

I connected the ground to the lower part of the fence.

I connected the ground to the lower part of the fence.

It went left and right from my feedpoint a long way, around 150 metres total.

It went left and right from my feedpoint a long way, around 150 metres total.

Here is my homemade extended inductor for topband, inside the MFJ-971 tuner. 29 turns on a T130-2 core (9.25uH). This works only when on the highest inductance setting.

This modification is shown in detail here.

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3 Comments

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  1. Great idea, John!

    But fences around here (in Texas) are mostly wood. What do you think about using a building’s metal rain-gutter? I do have the Icom AH-4 tuner with my IC-7200.

    -Say, how far are you from North Watford, in Hertfordshire?

    Thanks,
    73 Stu, k2qde
    Austin, TX

    Grid Square: EM10CL

    1. Hi Stu.

      Sure, It’s good fun to try anything different, so long as nobody is likely to touch it of course 😉
      North Watford is about an hour drive away from me.

      73, John M0UKD.

      1. Ok John,
        I’ll let you know next time we head over there. As a New Yorker, I fell in fell in love with Bath!

        The loaded rain gutter is the higher of the two at 32 feet. The lower run does not circle the building like the upper run. I just added a second counterpoise about 35 feet and that reduced ground loss a bit. It was then I realized, a counterpoise should run parallel and not perpendicular to the driven element. Much lower SWR on 30 through 6 meters, now.

        XYL and I are big fans of British TV and movies. Just heard the new Bond film starts shooting Dec. 6th. U.S. made TV shows are worthless! Please keep “Foyle’s War” going! It’s the top show over here.

        Cheers and 73,
        Stu, k2qde
        Austin, TX
        Grid: EM10CL

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