DG7YBN / 1296 MHz / GTV 23-46w Terminator
  Last Update May 7th, 2021




.......




Performance Data and Geometry
Pattern and VSWR
Download as File


GTV 23-46w  Yagi with bent Driven Element



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".

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


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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 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 through this plastic boom:





Sketch of Strut

The Drivers diameter is 4.763 mm.
The EZNEC model is done with Auto-Segmentation at 1296.2 MHz








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



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