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UHF H2 2-Bay Bowties + Screen Reflector
UHF H2 2-Bay Bowtie with Screen Grid Reflector Analyzed using 4nec2 after determining OPTIMUM Dimensions
using nikiml's Python Optimization Scrips.  Performance is significantly better than ANY other 2-Bay Bowtie.

Two versions are Optimized and Analyzed....the second clearly outperforming the first:

a) H2 (9.5"x12") 2-Bay Bowtie with 24"Hx24"W Screen Reflector (Grid=2"Hx4"W),
with Hi-VHF Gain to REAR on lower Channels:

UHF Raw Gain = 10.3 to 13.6 dBi, F/B & F/R Ratio Min. = 15.4 dB and SWR (300-ohms) under 2.3.
Hi-VHF Raw Gain = -2 to 8 dBi FORWARD and to REAR Raw Gain = 6.9 to 7.3 to 2.5 dBi with
Hi-VHF F/B & F/R = 10 to -5 dB and SWR (300-ohms) = 125 to 60.8.

Dimensions (inches):
BowLen = 9.5 = Bowtie Whisker Half-Length,
ZBowII = 12.0 = Distance between the Centers of the two Bowties,
TineSep = 8.25 = Bowtie Tine Separation,
BowSwp=0.0 = Bowtie Forward Sweep,
FedSep = 1.75 = Separation (in inches) between two FEEDLINE wires,
RS = -4.75 = Separation between Bowties and Reflector.
Screen Reflector = 24-in H x 24-in W, 2"Hx4"W Grid (1"Hx2"W would improve F/B & F/R Ratios).

======================================
b) H2 (10"x15") 2-Bay Bowtie with 36"Hx36"W Screen Reflector (Grid=1"Hx2"W), with significantly
higher UHF Gain and more Hi-VHF Gain aligned FORWARD:

UHF Raw Gain = 12.9 to 14.5 dBi, F/B & F/R Ratio Min = 22.5 dB and SWR (300-ohms) Under 2.8.
Hi-VHF Raw Gain = 8.2 to 8.6 dBi, F/B & F/R Ratio = 9.8 to 15.9 dB and SWR (300-ohms) = 93 to 31 is Excessive.

Dimensions: (inches)
BowLen = 10.0 = Bowtie Whisker Half-Length,
ZBowII = 15.0 = Distance between the Centers of the two Bowties,
TineSep = 10.0 = Bowtie Tine Separation,
BowSwp=0.0 = Bowtie Forward Sweep,
FedSep = 2.75 = Separation (in inches) between two FEEDLINE wires,
RS = -5.0 = Separation between Bowties and Reflector.
Screen Reflector = 36-in H x 36-in W, 1"Hx2"W Grid.
Date(s): 9 Feb 2015. Album by holl_ands. 1 - 42 of 42 Total. 2836 Visits.
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Enlarge photo 1
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1
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
3D View


Enlarge photo 2
enlarge 330KB, 1015x1024
2
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Front View
[1 large square = 2.5 inches]


Enlarge photo 3
enlarge 136KB, 506x1024
3
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Top View
[1 large square = 2.5 inches]


Enlarge photo 4
enlarge 182KB, 1024x741
4
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
UHF Raw Gain = 10.3 to 13.6 dBi
UHF F/B & F/R Ratio Minimum = 15.4 dB


Enlarge photo 5
enlarge 185KB, 1024x741
5
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
UHF SWR (300-ohms) Under 2.3


Enlarge photo 6
enlarge 227KB, 1024x741
6
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
UHF Impedance


Enlarge photo 7
enlarge 301KB, 1024x1024
7
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 470 MHz


Enlarge photo 8
enlarge 302KB, 1024x1024
8
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 530 MHz


Enlarge photo 9
enlarge 302KB, 1024x1024
9
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 590 MHz


Enlarge photo 10
enlarge 304KB, 1024x1024
10
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 650 MHz


Enlarge photo 11
enlarge 305KB, 1024x1024
11
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 698 MHz


Enlarge photo 12
enlarge 303KB, 1024x1024
12
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 758 MHz


Enlarge photo 13
enlarge 305KB, 1024x1024
13
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 806 MHz


Enlarge Microsoft Word Document 14
enlarge 40KB, 791x1024
DOC14
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
4nec2 File Contains Dimensions


Enlarge photo 15
enlarge 136KB, 499x1024
15
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Side View
[1 large square = 2.5 inches]


Enlarge photo 16
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16
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Hi-VHF Raw Gain = -2 to 8 dBi FORWARD


Enlarge photo 17
enlarge 169KB, 1024x741
17
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Hi-VHF Raw Gain = 6.9 to 7.3 to 2.5 dBi
MORE TO REAR on Lower Channels
Hi-VHF F/B & F/R 10 to -5 dB


Enlarge photo 18
enlarge 192KB, 1024x741
18
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Hi-VHF SWR (300-ohms) = 125 to 60.8


Enlarge photo 19
enlarge 305KB, 1024x1024
19
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 174 MHz
More Gain to REAR on Lower Channels


Enlarge photo 20
enlarge 313KB, 1024x1024
20
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 198 MHz
Bi-Directional Mid-Band


Enlarge photo 21
enlarge 308KB, 1024x1024
21
UHF H2-Bay (9.5"Hx12"W) Bowtie plus
Screen Reflector (24"Hx24"W), Grid=2"Hx4"W
Azimuthal Pattern at 216 MHz
More Gain FORWARD on Higher Channels


Enlarge photo 22
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22
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
3D View


Enlarge photo 23
enlarge 399KB, 1024x886
23
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Front View
[1 large square = 2.5 inches]


Enlarge photo 24
enlarge 137KB, 448x1024
24
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Top View
[1 large square = 2.5 inches]


Enlarge photo 25
enlarge 178KB, 1024x722
25
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
UHF Raw Gain = 12.9 to 14.5 dBi
UHF F/B & F/R Ratio Min = 22.5 dB


Enlarge photo 26
enlarge 184KB, 1024x722
26
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
UHF SWR (300-ohms) Under 2.8


Enlarge photo 27
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27
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
UHF Impedance


Enlarge photo 28
enlarge 301KB, 1024x1024
28
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 470 MHz


Enlarge photo 29
enlarge 300KB, 1024x1024
29
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 530 MHz


Enlarge photo 30
enlarge 300KB, 1024x1024
30
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 590 MHz


Enlarge photo 31
enlarge 299KB, 1024x1024
31
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W)
Azimuthal Pattern = 650 MHz


Enlarge photo 32
enlarge 300KB, 1024x1024
32
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 698 MHz


Enlarge photo 33
enlarge 302KB, 1024x1024
33
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 806 MHz


Enlarge photo 34
enlarge 168KB, 1024x722
34
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Hi-VHF Raw Gain = 8.2 to 8.6 dBi
Hi-VHF F/B & F/R Ratio = 9.8 to 15.9 dB


Enlarge photo 35
enlarge 190KB, 1024x722
35
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Hi-VHF SWR (300-ohms) = 93 to 31
is Excessive


Enlarge photo 36
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36
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Hi-VHF Impedance


Enlarge photo 37
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37
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 174 MHz


Enlarge photo 38
enlarge 293KB, 1024x1024
38
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 198 MHz


Enlarge photo 39
enlarge 297KB, 1024x1024
39
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
Azimuthal Pattern = 216 MHz


Enlarge Microsoft Word Document 40
enlarge 112KB, 791x1024
DOC40
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
4nec2 File Includes Summary of Dimensions


Enlarge Microsoft Word Document 41
enlarge 26KB, 791x1024
DOC41
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
EVAL Summary of Performance


Enlarge HTML Document 42
enlarge 76KB, 791x1024
HTML42
UHF H2-Bay (10"Hx15"W) Bowtie plus
Screen Reflector (36"Hx36"W), Grid=1"Hx2"W
EVAL *.html Performance Summary


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