DG7YBN / 144 MHz / UR5EAZ RS 2-12
  Last Update June 17th 2013


Performance Data and Geometry
Pattern and VSWR
Simulated Wet+Snow Degradation
Download as File

UR5EAZ RS 2-12 Yagi   with bent Reflector

I am proud to host UR5EAZ, Vladimir with his very wide band, high G/T 12 elem. Yagi design:

Vladimir does not have an own website but this nice design, so I decided to share a bit of my webspace.
Design, images and analysis are the property of UR5EAZ. You find his email address at the end of this site.

Like on the UA9TC the Moxon Beam like bent reflector helps in producing a pattern with very good F/B and little back lobe magnitudes in general
while keeping gain and especially band width on an exceptional level for the combination of all those properties. In case you wish to contact the
designer you find Vladimirs email address on the end of the page.

The Yagi prototype is built on a plastic lace dim. 24 x 28 mm as boom, elements are mounted on plexiglass [acryl] platforms on the boom.

Владимир, UR5EAZ, reports:

       "Photo: antenna UR5EAZ 12.

        Mechanical Designer: my friend Oleg UT4EU.
        Oleg - a very good mechanic.
        He has all the tools for precision work.

        Tnx Boris UA9TC for his RS-reflector in Yagi."

Performance Data

Gain vs. isotr. Rad.  15.5 dBi
Gain vs. Dipole       13.3 dBD
-3 dB H-plane         32.6 deg.
-3 dB E-plane         35.2 deg.
F/B                  -30.1 dB
F/R                  -24.0 dB
Impedance               50 ohms
Mechan. Length        6796 mm
Electr. Length        3.27 λ

Stacking Dist. h-pol.    DL6WU     max. G/T
top-to-bottom           3.44 m      3.xx m
side-by-side            3.71 m      3.xx m

Note: Last two wires (#13, #14) make the bent sides of the reflector

Pattern and VSWR Plots

Current distribution

Elevation and Azimuth plot at 144.1 MHz


SWR and Return Loss plots - simulated with 4nec2

NEC simulated degradation due to bad weather

Simulated layers of water, snow or ice are derived at by manipulating numbers for Dielectricum of wire = element insulation and its thickness.

Though match of numbers to real wet, snow covered or iced over Yagis are unknown yet, the intention is to show how stabile this design behaves
even under severe manipulation of the element's environment. (Charts by UR5EAZ)

  • Current peaks per element on single Yagi // wires 13 + 14 belong to bent reflectors edges

  • Current peaks on single Yagi as part of a 4-bay array


EZNEC file of this Yagi  

Mind that this antenna, data and analysis are numbers presented by UR5EAZ;
Contact Vladimir via if you wish for more details.

73, Hartmut, DG7YBN

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