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 Public Gallery | Home > Arts and Crafts Prev 15 | Next 15 
Arts and Crafts
16 - 30 of 572 Total. Shared
Hi-VHF Goalkeeper Quad-Trapezoid+Spurs
16. Hi-VHF Goalkeeper Quad-Trapezoid+Spurs  (22 Jul 2014)
Hi-VHF Goalkeeper, a Quasi-Omni [accidental] variation of the Quad-Trapezoid+Spurs
was analyzed using 4nec2.

Provides Bi-Directional Pattern firmly aligned along the X-Axis with 100-110 degrees Beamwidth
and NULLs to the sides.  Although Horizontally Polarized, it also provides both
Right-Hand and Left-Hand Circular Polarization.
24 Visits
12 Images
Linked Album
holl_ands
Hi-VHF Goalkeeper Quad-Trapezoid+Spurs
17. Hi-VHF Goalkeeper Quad-Trapezoid+Spurs  (22 Jul 2014)
Hi-VHF Goalkeeper, a Quasi-Omni [accidental] variation of the Quad-Trapezoid+Spurs
was analyzed using 4nec2.

Provides Bi-Directional Pattern firmly aligned along the X-Axis with 100-110 degrees Beamwidth
and NULLs to the sides.  Although Horizontally Polarized, it also provides both
Right-Hand and Left-Hand Circular Polarization.
35 Visits
12 Images
Linked Album
holl_ands
FM - Goalkeeper Quad-Trapezoid+Spurs
18. FM - Goalkeeper Quad-Trapezoid+Spurs  (22 Jul 2014)
FM - Goalkeeper, a Quasi-Omni [accidental] variation of the Quad-Trapezoid+Spurs
was analyzed using 4nec2.

Provides Bi-Directional Pattern firmly aligned along the X-Axis with 100-110 degrees Beamwidth
and NULLs to the sides.  Although Horizontally Polarized, it also provides both
Right-Hand and Left-Hand Circular Polarization.
48 Visits
12 Images
Linked Album
holl_ands
UHF Double Rhomboid
19. UHF Double Rhomboid  (10 Mar 2010)
UHF Double Rhomboid (18.4 ft long by 8.2 ft wide, AWG12) analyzed using 4nec2.
Although the differences were small, "best" value for Termination Resistors was 300-ohms.
1119 Visits
16 Images
Linked Album
holl_ands
UHF 2x2-Bay (H4) with Building Reflector
20. UHF 2x2-Bay (H4) with Building Reflector  (21 Jul 2014)
UHF 2x2-Bay Bowtie (H4) with Building used as a Reflector analyzed using 4nec2.  Separation from side of Building was assumed to be 4.5-inches.
45 Visits
15 Images
Linked Album
holl_ands
Hi-VHF Circular Loop + Reflector
21. Hi-VHF Circular Loop + Reflector  (15 July 2009)
Hi-VHF Circular Loop with either Loop or Screen Reflector analyzed using 4nec2.

a) With Loop Reflector, Net Gain was 8 dBi on Ch7, dropping to 6 dBi on Ch13 with excellent SWR, except for small increase on Ch7.

Adding Loop Reflector increased Net Gain by 2-4 dB (less at high freqs) with more than 8.7 dB F/B (and F/R) using

Optimum Diameter=22-in for Half-Inch Copper Tubing.  Best F/B (and F/R) is on Ch8-10.

Optimum Diameter=21.5-in for Quarter Inch Copper Tubing (QICT) was nearly as good, with more than 7.3 dB F/B (and F/R).
Smaller Circular Loop Element sizes not analyzed since a Square Loop (Quagi) would be easier to construct.

Loop Reflector dimensions are optimized for full Hi-VHF Band coverage.
Rescaling to optimize Ch7 will have only minor-moderate impact to Ch13 F/B, F/R and SWR.
However, rescaling to optimize Ch11-13 will degrade F/B, F/R and especially SWR on CH7-10.

b) EDIT (16 Sep 2009): Added analysis of alternative Hi-VHF Loop with 28x34-in Screen Reflector.

c) EDIT (5 Oct 2013): Added analysis of alternative Hi-VHF Loop with 40x40-in Screen Reflector to improve F/B & F/R Ratios.

d) EDIT (15 Jul 2014): Added Circular Polarization analysis of alternative Hi-VHF Loop with 28x34-in Screen Reflector.
2279 Visits
43 Images
Linked Album
holl_ands
Compare Loops
22. Compare Loops  (16 Jul 2014)
Charts Comparing Loop Performance.
540 Visits
8 Images
Linked Album
holl_ands
UHF Quad-Trapezoid-Loop
23. UHF Quad-Trapezoid-Loop  (11 Jul 2014)
UHF Quad-Trapezoid-Loop Antenna analyzed using 4nec2, formed by adding outer parts
of Chireix 2-Square to an Hourglass-Loop.  All dimensions determined using nikiml's
Optimization Scripts.

Two versions analyzed: Quad-Trap (NO Reflector) and Quad-Trap (15 RR).

=================================================
a) Quad-Trapezoid-Loop (NO Refl):

UHF Raw Gain = 6.7 to 8.4 to 7.8 dBi and SWR (300-ohms) under 1.8.

=================================================
b) Quad-Trapezoid-Loop + 15 Reflector Rods:

UHF Raw Gain = 10.1 to 11.8 dBi, F/B & F/R Ratio Min =19.2 dB and SWR (300-ohms) under 2.7.

Note the VERY WIDE BANDWIDTH, 60-degrees ALL across the UHF Band and the VERY DEEP
49+ dB Notch directly to the Rear.
2878 Visits
30 Images
Linked Album
holl_ands
V-Stack UHF Hourglass-Loop + 15RR
24. V-Stack UHF Hourglass-Loop + 15RR  (11 Jul 2014)
V-Stack UHF Hourglass-Loop + 15RR
UHF Vertically Stacked Hourglass-Loops with 15 Reflector Rods  analyzed using 4nec2
where nikiml's Python Optimization Scripts were used to Optimize dimensions of the
HVH (Hollands Vertical Harness) and  Separation between Hourglass-Loops.
2657 Visits
18 Images
Linked Album
holl_ands
Gabriella Remes Canadian Original Art
25. Gabriella Remes Canadian Original Art   (July 8, 2014)
Hello my Name is Gabriella Remes. I am a Canadian Local Artist and Paint for my Living. Up for Sale are these Painting of Different Scenes. My Favorites items
to Paint are Birds and Flowers. If there is anything you
like email me at gabriellaremes@yahoo.com.
5270 Visits
6 Images
Linked Album
wrestlingfanaticactionfigures
Paintings
26. Paintings 

I love to paint and create. I like painting animals and people and themed pieces. I use Acrylics, wax pencil, Guache, Graphite and sometimes Oils.

 

If you are interested in purchasing any of my art please contact me for details... call 979-943-8400

100 Visits
9 Images
Linked Album
halfmoon
27. Rob & Pamela 6-14 
7 Visits
0 Images
Linked Album
fstopshere
Castaways 2014
28. Castaways 2014  (May 2014)
Castaways Sculpture Awards is an annual art competition that has been running since 2008. Castaways melds the theme of recycling and environment awareness with the creative re-use of materials and innovative sculpture. Each May, more than 50 sculptures grace the Rockingham foreshore creating opportunities for emerging artists to showcase their artworks, together with creative entries from local schools.  More than 15,000 visitors attend the exhibition each year, delighting in the innovative use of recycled materials.
671 Visits
96 Images
Linked Album
gladysclancy
Homebrewing
29. Homebrewing  (ongoing)
Equipment etc
175 Visits
11 Images
Linked Album
bigchriscase
2014 - Have I Got News For You
30. 2014 - Have I Got News For You  (April 4-6, 2014)
273 Visits
21 Images
Linked Album
hpdramaclub
 
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