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 YBN 705m
A 0.5 m 432 MHz blue print of the YBN 25m 50 ohms
high F/B direct feed 144 MHz Low Noise Yagi 3D Plot
 YBN 7014wz
Tune up your 19 ele. Tonna!A design based on the hardware of the F9FT,
turning it into a 14 ele. OWL with cleaner pattern, +0.3 dB gain and SWR less than 1.2 from 430 to 440 MHz Azimuth Plot
 GTV 702w
A 0.14 m GTV useful for portable operation and up to the satellit band
and handheld activities of any kind Elevation Plot
 GTV 703w
A 0.21 m GTV useful for portable operation and up to the satellit band
and lower noise stacks of any kind Elevation Plot
 GTV 704m
A 0.34 m GTV useful for portable operation up to the satellit band
and lower noise stacks of any kind Elevation Plot
 GTV 707n
A 1.1 m 432 MHz blue print of the low impedance, yet 50 ohms
direct feed 144 MHz Low Noise Yagi introduced in Dubus 1/2013 Elevation Plot
 GTV 708n
A 1.3 m 432 MHz GTV with high gain but low backlobe volume. Makes
a very compact 4 Yagi bay for QRP EME or contesting.
Elevation Plot
 GTV 709w
A 1.44 m GTV ment to be useful as a vertical stack for contesting
or be an ideal small size portable Yagi Elevation Plot
 GTV 7011w
A 2.01 m GTV ment to be useful as a vertical stack for contesting
or be an ideal small size portable Yagi or minimum size EME 4 bay Elevation Plot
 GTV 7014m
2.9 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7017m
3.7 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7019m
4.2 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7023m
5.3 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7025m
5.9 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7030m
7.3 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7034w
8.5 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot
 GTV 7046w
12.0 m version of the low impedance, yet 50 ohms
direct feed Low Noise Yagi with bent DE introduced in Dubus 1/2013 Elevation Plot

....... 
Performance Data and Geometry
Pattern and VSWR
Stacking
Matching
GTV 7034w Yagi with bent Driven Element
432.1 MHz EME to 436 MHz Longyagi as Wideband Antenna Version (OWAstyle)
This Yagi has very low back lobes for its length. It may serve as single antenna for Tropo
or make a nice 4 Yagi EME array. It also makes a quiet contest antenna due to its high F/B.
The bent DE (K6STI style) transforms from approx. 17 ohms to 50 ohms at feed point.
What else? With this Yagi I stopped producing more forward gain keeping the directivity factor
at a point that i see as uncritical still for producing nicely working real world builds.
Antenna G/T can be pushed further but with increase of Antenna Temperature mainly.
Which I did not want to do. In my understanding the 34 element Yagi should not hold a higher
Antenna Temperature than the GTV7030m.
The GTV7034w produces a solid 0.5 dB higher Ant.G/T compared to the GTV7030m which by
all means should show in its performance for EME and other Low Noise operations.
Current distribution
Performance Data
Specs: with 8 mm elements @ 432.1 MHz
Gain vs. isotr. Rad. 20.3 dBi
Gain vs. Dipole 18.2 dBD
3 dB Eplane 19.6 deg.
3 dB Hplane 20.0 deg.
F/B 40.5 dB (34 dB)
F/R 33.8 dB
Impedance 50 ohms
Mechan. Length 8455 mm
Electr. Length 12.18 λ
Stacking Dist. hpol. acc the DL6WU formula
toptobottom 1.998 m
sidebyside 2.038 m
Geometry
Geometry for 8 mm elements
The Drivers diameter is 10 mm for all examples.
Use EZNEC's AutoSegmentation at 1050 MHz.
A simple symmetrising member may be made from a 3 x 1/4 Lambda line grounded at the far side with
Nflangebushing and an aluminium plate and ferrite added as close as possible to the DE, see below.
How many OMs have been looking up this design?
Geometry
Ø8 mm Elements  On Boom  Dimensions (BC acc. DG7YBN)
Actual BC for on a 25 x 25 mm Boom with standard insulators is 11.0 mm, SBC is 1.37 mm,
total length to add is ~ 12.4 mm
Using a large calliper gauge to control element lenghts to a 10th of a millimeter is a must.
Pattern and VSWR Plots
Elevation and Azimuth plot at 432.1 MHz
SWR and Return Loss plots  simulated with 4nec2
Stacking
As on the 432 MHz Band the Yfactor = T_earth / T_sky is that high I see little chances in
bettering an array's RX performance by using "Over Stacking" distances. However, depending
the level of local QRM it might be worthwhile to try less distance, especially in Hplane.
Stacking Dist. DL6WU Formula
Hplane 2.00 m
Eplane 2.04 m
Elevation and Azimuth plot and data of 4 Yagi bay using DL6WU stacking distances
AGTC_lite screenshot of this Yagi with 8 mm elements
Gain vs. isotr. Rad. 26.10 dBi
Gain vs. Dipole 23.95 dBD
3 dB Hplane, appr. . deg.
3 dB Eplane, appr. . deg.
F/B . dB
F/R . dB
T_ant 26.2 K*
G/T 11.91 dB*
Theoretical numbers, no phasing line losses
nor imperfections caused by Hframe included
*) T_sky = 20 K, T_earth = 350 K as in VE7BQH G/T table
Symmetrising 50 to 50 ohms Feedline to 432 MHz Bent DE
The principle is similar to the 1/4 Lambda coax. Adding 2 x 1/4 Lambda or a half wave line does not change anything but allows
to form a gentle bow below the boom or until behind the Reflector. Follow practical construction hints on "Building a Yagi" page.
Attenzione!
Take care when lengthening the coax, measure the right length instead of refering to given vfactors only.
A good choice may be the diam. 5 mm PTFE coax RG142 B/U: real resonate length (432.2 Mhz as 3/4 Lambda) shieldshield is around 348 mm
Find more information on Phasing & Matching Lines page
73, Hartmut, DG7YBN

