I promised to upload some phots here so here they come:
In the first photo you see the antenna from behind, the feedpoint is closest to the birch in the middle of the picture.
In the second photo you can see the feedpoint to the left and also get an impression of the layout of the antenna with the 1/4 wavelenght stubs in the corners of the square-shaped loop.
The dimensions you may find in my earlier text. One ft is 0.305 meters.
Edit Nov. 18 2008:
As I see that I get many hits to this antenna-blog I will paste the text from the preceeding blog here:
The basic OH6MY multiband antenna for 40 - 10 m. is as follows:
-the base is a square-shaped loop for 40 m, installed parallell to the ground
-1/4 wavelenght stubs (on 40m) added in two opposite corners.
-the antenna will resonate as a dipole on 80 m. as well if there are some 2.5 m "whiskers" added to the shorted ends of the stubs
-antenna wire is 2 mm diameter enamelled Cu-wire
-each side of the loop is 11.1 m.
-each stub is 9.1 m. of polyethylene coated 450 ohm ladder line or (theoretically) 10.1 m home-made 450 ohm ladder made from the same wire as the antenna. I built this using the polyethylene coated line.
I built and tested at approx 8 m. above ground at my summer house (sorry Ingela...)the stubs in the corners are falling down perpendiculary to the plane of the antenna for some few meters and then sloping sidways-outwards, the shorted ends are at approx. 1 m. above ground. Added 2.5 m. of the same wire to the end of the stubs, parallell with the ground to bring it into 80 m.
Different heights and/or ground properties would need slightly different stub lengths, start with 9.5 m and search for the point of resonance on 40 m by moving the shorting point upwards in increments of 5 - 10 cm. The resonance is fairly sharp. Whenever it is in resonance on 40 m. it will be on the upper bands as well.
If you bild and test this antenna, please give me a shoutout per e-mail at:
hans.astrom@netikka.fi
73:s
Hans
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