Gain vs. isotr. Rad.   8.24 dBi
Gain vs. Dipole        6.1 dBD
-3 dB E-plane         62.6 deg.
-3 dB H-plane         99.0 deg.
F/B                  -20.4 dB
F/R                  -12.5 dB
Impedance               50 ohms
Mechan. Length        5470 mm plus boom offsets
Electr. Length        0.39 λ

Stacking Dist. h-pol. (21.30 MHz)
top-to-bottom          9.25 m

Geometry

For building on a 50-60 mm boom, 25 mm mid-element tubes insulated with hydraulic clamps like from co. Stauff:

How many pageviews did this design get since Juni 2026?

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Pattern and VSWR Plots

Elevation and Azimuth plot at 21.30 MHz

 

SWR and Return Loss plots - simulated with 4nec2

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Radiation pattern with Ground Gain

At 14 m above perfect ground

At 14 m above perfect ground

Gain vs. isotr. Rad.  13.5 dBi  at  14 deg.
Gain vs. Dipole       11.3 dBD
F/B                  -18.8 dB   at 167 deg.

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Stacking

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73, Hartmut, DG7YBN