DG7YBN - GTV 23-46w

Performance Data and Geometry

Pattern and VSWR

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GTV 23-46w Yagi with bent Driven Element (K6STI style)

A long 23 cm Yagi that provides a very clean pattern and almost 22 dBi of gain.
This is the scaled version of the 70 cm band GTV 70-46w modified to deliver as
much forward gain as seems wise. Design date of issue: 2021.05.07

Terminator themes:

As this Yagi is planned to match any other similar length 23 cm antenna, if Yagi or Loopyagi,
we named her "Terminator".

Call for Arnie look alike photos: You built the Terminator GTV 23-46m?
Send your Arnie look alike portrait and I will add it to the gallery!

GTV 23-46w 3D pattern plot at 1296.2 MHz

Performance Data

Specs: with 3.2 mm elements @ 1296.2 MHz


Gain vs. isotr. Rad.  21.9 dBi
Gain vs. Dipole       18.1 dBD
-3 dB E-plane         15.6 deg.
-3 dB H-plane         16.0 deg.
F/B                  -39.5 dB
F/R                  -35.3 dB
Impedance               50 ohms
VSWR Band Width       1.11:1 *
Mechan. Length        3992.2 mm plus 2 x 70 mm offset
Electr. Length        17.3 λ

Stacking Dist. h-pol. (1296.2 MHz)
top-to-bottom         0.83 m or 2.73 ft
side-by-side          0.85 m or 2.80 ft

*) at 1300.0 MHz

How many VHF operators have been looking up this design since May 2021?

Geometry

This Yagi with 3.2 mm elements

Ele. 3.2 mm
DE 4.0 mm
Boom 7.5 x 7.5 mm ABS Plastic

Ele. fastening &. photo acc. F4FEY

"Ready to saw and drill" data for mounting elements through this plastic boom:

Coming soon ...

The Drivers diameter is 4 mm.
The EZNEC model is done with Auto-Segmentation at 1296.2 MHz

This Yagi with 4.00 mm elements

Boom shape: square
Boom dim: 15 x 15 mm
Wall thickn.: 1.0 mm
Holes in boom: 6.0 mm
Offset rear: 70 mm
Offset front: 70 mm

"Ready to saw and drill" data for mounting elements insulated through boom:

The Drivers diameter is 5.0 mm.

This Yagi with 3/16 inch = 4.763 mm elements

Boom shape: square
Boom dim: 5/8 x 5/8 inch
Wall thickn.: 1.6 mm
Holes in boom: 7.5 mm
Offset rear: 70 mm
Offset front: 70 mm

"Ready to saw and drill" data for mounting elements insulated through boom:

The EZNEC model is done with Auto-Segmentation at 1296.2 MHz

Sketch of Strut for all versions

Pattern and VSWR Plots

Elevation and Azimuth plot at 1296.2 MHz

Return Loss and SWR plots - simulated

and same span as in Anritsu Sitemaster real Yagi plot:
Note aimed frequency is ~ 1 MHz higher then operating frequency to give the Yagi a bit of headroom when wet.

2nd Set of Plots

VSWR 1:1.03 at 1296.49 MHz

Return Loss -37 dB at 1296.49 MHz

Z = 50.9 + 0.9 ohms at 1296.49 MHz

Downloads

None so far.

73, Hartmut, DG7YBN