W-8010 5 band trap dipole antenna

LA1SSA Tore Aasli

For those of us using this antenna from Diamond, cutting (trimming) this antenna can be a bit tricky. Fortunately Diamond has a cutting procedure which is explained in the set-up instruction.

I have made a computer program to come to the aid of trimming this antenna. Here are two sample screenshots to explain how it's done (click on an image to view it):

This program example shows the antenna SWR before trimming.

From the cutting form, it's calculated that the 80 m band should be cut by 18 cm,
40 meter band by 12.7 cm
20 meter band by 4 cm
15 meter band by 6 cm
10 meter band by almost 5 cm

These are approximate figures. It's better to cut the antenna's trimming wires with about 50-70 % to begin with. And then run a MiniVNA test once more to check the cutting form.

This example shows the antenna before trimming, with SWR and Rs plotted in the same graph.

You can combine different plottings: Reflected power, Z, Xs or just the SWR.

To change axis step, click on the graph and choose another step value. Or right-click on the graph to Save it.

If you are interested in using this nifty program, please contact me for a download link (it's free!).

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14.10.09