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UHF Hourglass Loop
UHF Hourglass Loop analyzed using 4nec2 after finding "best" dimensions using nikiml's Optimizations Scripts.
Based on UHF Hourglass Loop posted by oneolddude in www.digitalhome.ca forum.
However Optimization and Rescaling increased 470 MHz Gain by about 0.5 dB with Max Gain on 698 MHz.

Five versions are analyzed here.  ALL provide very wide Beamwidths (60-50 degrees even at High Freqs):

#############################################
a) AWG6 or AWG12/10 with NO Reflector Rods (Optimization search across ALL THREE Variables):

UHF Raw Gain = 4.7-6.0 dBi with Excellent SWR under 1.6, using AWG6.
UHF Raw Gain = 5.0-6.0-5.2 dBi with Excellent SWR under 2.0, using AWG12 (or AWG10).

#############################################
b) AWG10 Elements + 1/4" 11x Reflector Rods (Optimization search across ALL THREE Variables):

USB Raw Gain = 9.3 to 10.3 dBi, F/B & F/R Ratio = 19.4 dB and SWR (300-ohms) Under 2.4

#############################################
c) AWG6 Elements + 1/4" 15x Reflector Rods (Search across ALL SIX Variables):

UHF Raw Gain = 9.6 to 10.4 to 10.3 dBi, F/B & F/R Minimum = 19.6 dB and  SWR (300-ohms) Under 1.8.

#############################################
d) AWG12 Elements + AWG12 15xReflector Rods:

UHF Raw Gain = 9.4 to 10.2 dBi, F/B & F/R Minimum = 17.1 dB and SWR (300-ohms) Under 1.8.

#############################################
e) Grid Mesh 24x19.5-in (per 300-ohm post):

UHF Raw Gain = 9.4-10.8 dBi with SWR under 2.4, using AWG6.
Front/Back and Front/Rear Ratios 15 dB or better.

#############################################
f) Grid Mesh 24x19.5-in (Re-Optimized using nikiml's Python scripts):

UHF Raw Gain = 9.5-10.6 dBi with SWR under 2.5, using AWG6.
Front/Back and Front/Rear Ratios 17 dB or better.

PS: For improved F/B and F/R Ratios, should try different Grid Mesh sizes.

EDIT (10Dec2012): Added 4nec2 analysis with Grid Mesh (per 300ohm post) and
Re-Optimized version, with somewhat better F/B and F/R Ratios.

EDIT (10Jul2014): Replaced 15xRR version with improved SWR version (with 0.2 drop in Gain).

EDIT (8Mar2015): Added 11RR version.
Date(s): 30 Nov 2012. Album by holl_ands. 1 - 81 of 81 Total. 0 Visits.
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UHF Hourglass Loop - No Reflector
3D View


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UHF Hourglass Loop - No Reflector
Front View - AWG-10 Version
Total Height = 13.0-in, Width = 10.25-in,
Feedpoint Gap=3.0-in, Diagonals = 7.5-in
[1 big box = 1.25 inches]


Enlarge Microsoft Word Document 3
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DOC3
UHF Hourglass Loop - No Reflector
4nec2 File - oneolddude's modified


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UHF Hourglass Loop - No Reflector
UHF Raw Gain = 4.7 to 5.9 dBi


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UHF Hourglass Loop - No Reflector
UHF SWR (300-ohms) Under 2.0


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UHF Hourglass Loop - No Reflector
UHF Impedance


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UHF Hourglass Loop - No Reflector
Azimuthal Pattern at 470 MHz


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UHF Hourglass Loop - No Reflector
Azimuthal Pattern at 590 MHz


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UHF Hourglass Loop - No Reflector
Azimuthal Pattern at 698 MHz


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UHF Hourglass Loop - No Reflector
Azimuthal Pattern at 758 MHz


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UHF Hourglass Loop - No Reflector
Azimuthal Pattern at 806 MHz


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DOC12
UHF Hourglass Loop - No Reflector
Python Optimization Control *.bat file


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UHF Hourglass Loop - No Reflector
Hi-VHF Raw Gain - 3.8 to 3.9 dBi


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UHF Hourglass Loop - No Reflector
Hi-VHF SWR (300-ohms) = 222 to 62 is Excessive


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UHF Hourglass Loop - No Reflector
Hi-VHF Impedance


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UHF Hourglass Loop - 11 Reflector Rods
3D View - AWG10 & 1/4" RR Version


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UHF Hourglass Loop - 11 Reflector Rods
Front View - AWG10 & 1/4" RR Version
Hourglass Height = 12.5-in, Width = 10.125-in,
Feedpoint Gap=2.5-in.
Overall Height with Refl Rods= 20.0-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 11 Reflector Rods
Top View - AWG6 & 1/4" RR Version
Refl Rod Length = 21.0-in,
Rod-to-Rod Separation=2.0-in,
Rods-to-Hourglass Separation=4.0-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 11 Reflector Rods
USB Raw Gain = 9.3 to 10.3 dBi
USB F/B & F/R Ratio = 19.4 dB


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UHF Hourglass Loop - 11 Reflector Rods
USB SWR (300-ohms) Under 2.4


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UHF Hourglass Loop - 11 Reflector Rods
USB Impedance


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 470 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 530 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 590 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 650 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 698 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 758 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 806 MHz


Enlarge Microsoft Word Document 32
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DOC32
UHF Hourglass Loop - 11 Reflector Rods
4nec2 File Contains Summary of Dimensions


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UHF Hourglass Loop - 11 Reflector Rods
Side View - AWG6 & 1/4" RR Version
Rod-to-Rod Separation=2.0-in,
Rods-to-Hourglass Separation=4.0-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 11 Reflector Rods
Hi-VHF Raw Gain TO REAR = 5.9 to -1.9 dBi
Hi-VHF F/B & F/R Ratio = 0.3 to -8.2 dB
MORE GAIN TO REAR


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UHF Hourglass Loop - 11 Reflector Rods
USB Raw Gain FORWARD = 5.6 to 6.3 dBi


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UHF Hourglass Loop - 11 Reflector Rods
USB SWR (300-ohms) = 1471 to 332
is Excessive


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 174 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 198 MHz


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UHF Hourglass Loop - 11 Reflector Rods
Azimuthal Pattern at 216 MHz


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UHF Hourglass Loop - 15 Reflector Rods
3D View - AWG6 & 1/4" RR Version


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UHF Hourglass Loop - 15 Reflector Rods
Front View - AWG6 & 1/4" RR Version
Hourglass Height = 12.75-in, Width = 9.75-in,
Feedpoint Gap=2.75-in, Diagonals = 7.22-in.
Overall Height with Refl Rods= 24.75-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 15 Reflector Rods
Side View - AWG6 & 1/4" RR Version
Refl Rod Length = 21.0-in,
Rod-to-Rod Separation=1.75-in,
Rods-to-Hourglass Separation=4.5-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
UHF Raw Gain = 9.6 to 10.4 to 10.3 dBi
UHF F/B & F/R Minimum = 19.6 dB


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
UHF SWR (300-ohms) Under 1.8


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
UHF Impedance


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UHF Hourglass Loop - 15 Reflector Rods
AWG12 & AWG12 RR Version
UHF Raw Gain = 9.4 to 10.2 dBi
UHF F/B & F/R Minimum = 17.1 dB


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UHF Hourglass Loop - 15 Reflector Rods
AWG12 & AWG12 RR Version
UHF SWR (300-ohms) Under 1.8


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UHF Hourglass Loop - 15 Reflector Rods
AWG12 & AWG12 RR Version
UHF Impedance


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 470 MHz


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 530 MHz


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 590 MHz


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 650 MHz


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 698 MHz


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 758 MHz


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UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
Azimuthal Pattern at 806 MHz


Enlarge Microsoft Word Document 56
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DOC56
UHF Hourglass Loop - 15 Reflector Rods
AWG6 & 1/4" RR Version
4nec2 File  [May change to 0.0404 for AWG12]


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UHF Hourglass Loop - 15 Reflector Rods
Side View - AWG6 & 1/4" RR Version
Refl Rod Length = 21.0-in,
Hourglass Width=9.75-in,
Rods-to-Hourglass Separation=4.5-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
3D View


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Front View - AWG-10 Version
Hourglass Height = 13.5-in, Width = 8.5-in,
Feedpoint Gap=3.75-in, Diagonals = 7.15-in.
Grid Reflector Height = 24.0-in, Width = 19.5-in.
Grid Size =  1.5-in x 1.5-in.


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Side View
Reflector-to-Hourglass Separation = 3.75-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
UHF Raw Gain = 9.3 to 10.9 dBi
Note lower F/B and F/R Ratios than 15 Refl Rods


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
UHF SWR (300-ohms) Under 2.4


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
UHF Impedance


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Azimuthal Pattern at 470 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Azimuthal Pattern at 590 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Azimuthal Pattern at 698 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Azimuthal Pattern at 758 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Azimuthal Pattern at 806 MHz


Enlarge Microsoft Word Document 69
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DOC69
UHF Hourglass Loop - 24x19.5-in Grid Reflector
4nec2 File - 300ohm's modified


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
3D View


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized AWG-10 - Front View
Hourglass Height = 14.5-in, Width = 10.75-in,
Feedpoint Gap=2.75-in, Diagonals = 8.25-in.
Grid Reflector Height = 24.0-in, Width = 19.5-in.
Grid Size =  1.5-in x 1.5-in.


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized - Side View
Reflector-to-Hourglass Separation = 3.5-in.
[1 big box = 2.5 inches]


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
UHF Raw Gain = 9.4 to 10.6 dBi (only 0.3 db less)
F/B and F/R Ratios improved to 17 dB or higher


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
UHF SWR (300-ohms) Under 2.5


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
UHF Impedance


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
Azimuthal Pattern at 470 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
Azimuthal Pattern at 590 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
Azimuthal Pattern at 698 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
Azimuthal Pattern at 758 MHz


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UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
Azimuthal Pattern at 806 MHz


Enlarge Microsoft Word Document 81
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DOC81
UHF Hourglass Loop - 24x19.5-in Grid Reflector
Re-Optimized
4nec2 File - Hourglass & Separation Re-optimized


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