
Performance Data and Geometry

Phasing

Pattern and VSWR

Download as File

Stacking

4 x vertical Phased Contest Stack
YBN 2-7mz 28 Ω Yagi with straight Driven Element
A 28 ohms low Q, low noise Yagi derived from the well tested 5-8 series.
Design focus was on clean rear, as single Yagi and also when errecting vertical stacks paired with insensitivity against weather influences or slightly bent elements and such.
Operation target was a rugged, simple to build an handle while going portable and extremely simple to phase antenna for contest stacks.
With 28 ohms at feedpoint this design is suitable for a straight forward phasing cables concept as shown by OK1NOR / DG7YBN
in '144 MHz seamlessly phased 4 x 28 Ohms Low Noise Yagi Stack' in Dubus 1/2023. Using 75 ohms coaxes of odd multiples of 1/4 wl we get 4 x 200 ohms
at the sum point, which results in 50 ohms total.
Design date of issue: 2022.11.23

YBN 2-7mz 3D pattern plot at 144,1 MHz

•
Online Article by Jindra, OK1NOR regarding the phasing scheme, building details, 3D print parts and more
https://docs.google.com/document/d/1VuFQeoNp1A_FRTOhJF6g-ddP92rVCGXSWLYaGIIz1rE/edit?invite=CJOjmf8N
Performance Data
Specs: with 10 mm elements @ 144.
3 MHz
Gain vs. isotr. Rad. 12.24 dBi
Gain vs. Dipole 10.1 dBD
55-3 dB E-plane 45.0 deg.
-3 dB H-plane 53.0 deg.
F/B -34.1 dB
F/R -22.6 dB
Impedance 28 ohms
VSWR Band Width 1.23:1 *
Mechan. Length 2758 mm plus 2 x 40 mm offset
Electr. Length 1.33 λ
Stacking Dist. h-pol. (144.3 MHz)
top-to-bottom 2.331 m or 7.6 ft
side-by-side 2.718 m or 8.9 ft
*) as in VE7BQH G/T table = at 145.00 MHz
How many VHF operators have been looking up this design since March 2023?
3 x 4 x vert. YBN2_7mz built by OK1NOR at OL7M during July 2023 ctest

YBN2_7mz built by OK1NOR at OL7M during MMC 2022

Building phase for a serious array of 18 YBN 2-7mz Yagis:
Dipoles with symmetrising 'Bazooka' choke:

Pre-assembling of 18 + 1 Yagis


Geometry
This Yagi with 10 mm elements on a 20 x 20 mm boom with standard insulators
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Ele. 10.0 mm
DE 10.0 mm
Boom 20 x 20 mm
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"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

This Yagi with 10 mm elements on a 25 x 25 mm boom with standard insulators
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|
Ele. 10.0 mm
DE 10.0 mm
Boom 25 x 25 mm
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|

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"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

This Yagi with 8 mm elements on a 20 x 20 mm boom with standard insulators
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Ele. 8.0 mm
DE 10.0 mm
Boom 20 x 20 mm
|
|

|
"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

This Yagi with 8 mm elements on a 25 x 25 mm boom with standard insulators
|
|
Ele. 8.0 mm
DE 10.0 mm
Boom 25 x 25 mm
|
|

|
"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

This Yagi with 6 mm elements on a 20 x 20 mm boom with standard insulators
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Ele. 6.0 mm
DE 10.0 mm
Boom 20 x 20 mm
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|

|
"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

This Yagi with 6 mm elements on a 25 x 25 mm boom with standard insulators
|
|
Ele. 6.0 mm
DE 10.0 mm
Boom 25 x 25 mm
|
|

|
"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

This Yagi with 4 mm elements on a 20 x 20 mm boom with standard insulators
NOTE: the shown insulators will not hold a 4 mm element!
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Ele. 4.0 mm
DE 10.0 mm
Boom 20 x 20 mm
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|

|
"Ready to saw and drill" data for mounting elements on boom with BC according DG7YBN for standard insulators
as sold by WiMo, Tino's Funkshop, HF-Kits NL, 7arrays:

The Drivers diameter is 10 mm for all examples.
The EZNEC model is done with Auto-Segmentation at 380 MHz, SBC = 2.52 mm

Pattern and VSWR Plots
Elevation and Azimuth plot at 144.3 MHz

Return Loss and SWR plots - simulated


Phasing


There are 75 ohms high quality, low loss coax cables available:
For instance
Italian company Messi & Paoloni:
• INTSAT 170 ELITE, 10 mm diameter
• INTSAT 220 ELITE, 13 mm diameter

Downloads
None so far.

Stacking
Stacking Dist. DL6WU Formula (144.1 MHz)
E-plane 2.718 m
H-plane 2.331 m
Plot and data of 2 vertically stacked YBN YBN 2-7mz using DL6WU stacking distances -10 percent
Antenna View & Elevation Pattern

Plot and data of 3 vertically stacked YBN YBN 2-7mz using DL6WU stacking distances -10 percent
Antenna View & Elevation Pattern

Same with lowest Yagi at 9 m agl, perfect ground assumed

Plot and data of 4 vertically stacked YBN 2-7mz using DL6WU stacking distances -10 percent
Antenna View & Elevation Pattern

4 x vert. stack with lowest Yagi 9.0 m abover 'Perfect Ground'
F/B approx. -31 dB

Plot and data of 4 vertically STAGGER stacked YBN YBN 2-7mz using DL6WU stacking distances, 502mm shift
Lowest Yagi 9.0 m agl, highest Yagi 16.3 m agl.
18,3 dBi or > 16.1 dBd at close to 46 deg. HPBW in Azimuth with > -39 dB of F/B.


Elevation Pattern
4 x vert. stagger phased stack with lowest Yagi 9.0 m abover 'Perfect Ground'
F/B better -39 dB


Plot and data of classical H-shape bay of YBN 2-8mz using DL6WU stacking distances
Antenna View & Elevation Pattern


Antenna G/T:


73, Hartmut, DG7YBN