Gain vs. isotr. Rad.  17.55 dBi
Gain vs. Dipole       15.4 dBD
-3 dB E-plane         25.6 deg.
-3 dB H-plane         26.8 deg.
F/B                  -35.3 dB
F/R                  -30.2 dB
Impedance               50 ohms
VSWR Band Width     1.08:1 *
Mechan. Length       11740 mm incl. 2 x 40 mm offset at boom ends
Electr. Length        5.60 λ

Stacking Dist. h-pol.
top-to-bottom         4.49 m or 14.7 ft
side-by-side          4.69 m or 15.4 ft

*) as in VE7BQH G/T table = at 145.00 MHz

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Geometry

Segmented using EZNEC Auto Segmentation (Conservative Mode) at 350 MHz.

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Table 1: GTV 2_18w, 8 mm elements on a 25 x 25 mm boom:

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"Ready to saw and drill" data for mounting elements on boom with standard insulators. BC according DG7YBN:

Boom shape: square Boom dim: 25 x 25 mm

Note: This includes a "Segmentation Density Correction" (SBC) of 1.17 mm

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Table 2: GTV 2_18w, 8 mm elements on a tapered boom 20 x 20 and 25 x 25 mm boom:

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"Ready to saw and drill" data for mounting elements on boom with standard insulators. BC according DG7YBN:

Boom shape: square Boom part 1: 20 x 20 mm Boom part 2: 25 x 25 mm Boom part 3: 20 x 20 mm

Note: This includes a "Segmentation Density Correction" (SBC) of 1.17 mm

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Sketch of Bent Dipole

This design has been viewed how often after the first built has been published in Nov. 2019?

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Serving Suggestion

It is understood that it is vital for such a long beam of rather limited thickness
that we support it with a 3 dimensional stucture. Which might be produced by
the combination of a strut and two v-shape guy wires to front and back. With sufficent
stiffness to prevent the whole thing from shaking in wind gales which animate it to
vibrate in 1st or 3rd natural mode.

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Pattern and VSWR Plots

Current distribution Elevation and Azimuth plot at 144.1 MHz

 

RL and SWR plot - simulated: 144.0 - 146.0 MHz

RL and SWR plot - simulated: 142.0 - 148.0 MHz

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Downloads

One so far ...

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X-pol Details


• Plane Offset is 584 mm.


Click on image to enlarge



• Stacking Distance is 4.59 m as average of h-pol. and v-pol. distances acc. DL6WU

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Stacking

• DL6WU distances: 3D pattern simulation with 4nec2's 3D viewer

Stacking acc. DL6WU

Stacking Dist.    DL6WU Formula
E-plane               4.49 m or 14.7 ft
H-plane               4.69 m or 15.4 ft

X-pol Stacking Dist.
4.59 m each plane

Gain vs. isotr. Rad.  23.45 dBi
Gain vs. Dipole       21.3 dBD
-3 dB H-plane  approx. 6   deg.
-3 dB E-plane  approx. 5.8 deg.
F/B                  -35.9 dB
F/R                  -31.9 dB
T_los                  6.5 K
T_ant                374.5 K*
G/T                  -2.28 dB*

Stacking Dist.    DL6WU Formula
E-plane               4.49 m x 0.88 = 3.95 m
H-plane               4.69 m x 0.88 = 4.13 m

X-pol Stacking Dist.
4.04 m each plane

Stacking Dist.    DL6WU Formula
E-plane               4.49 m x 1.08 = 4.85 m
H-plane               4.69 m x 1.08 = 5.06 m

X-pol Stacking Dist.
4.04 m each plane

The GTV 2-18w overstacked at +8 percent of DL6WU distance
in a fictive Antenna G/Ta table:

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73, Hartmut, DG7YBN