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I started modelling antennas in 2018 to help with building them. Sometimes I would want to tweak a design a bit to help with the construction or performance, so I could make those changes and check the simulation results with 4nec2 before building an antenna. These are the results of the more notable designs I've modelled.
nu-Gray Hoverman (470-608 MHz UHF)
This Hoverman design was worked on by nikiml, holl_ands, and Yurii Pylypenko. I slightly modified the design for the new UHF band (470-608 MHz). The GH wire is AWG10 and the reflector wire is AWG16 'hardware cloth' with 1" x 1" grid spacing (only the outline is shown below). Total size is 36" x 36" with the reflector sitting 4" behind the driven elements. I use two of these pointed in different directions for local and dx reception, with 0.5" x 0.5" reflector grid spacing for higher F/B & F/R ratios.
» RAW GAIN (dBi): 13.7 to 15.5
» F/B & F/R Ratio: >20 dB
» SWR: <1.9
View .nec file HERE
nu-Gray Hoverman Horizontal Stack (470-608 MHz UHF)
This is a horizontal stack of two nuGH antennas connected with equal length coax cables into a splitter in reverse. The GH wire is AWG10 and the reflector wire is AWG16 'hardware cloth' with 1" x 1" grid spacing (only the outline is shown below). Total size is 64" x 36" with the reflector sitting 4" behind the driven elements.
» RAW GAIN (dBi): 16.4 to 18.2
» F/B & F/R Ratio: >20 dB
» SWR: <1.9
View .nec file HERE
nu-Gray Hoverman Compact Quad Stack (470-608 MHz UHF)
This is a "compact" horizontal + vertical stack of four nuGH antennas. The GH wire is AWG10 and the reflector wire is AWG16 'hardware cloth' with 2" x 2" grid spacing (use 1" x 1" grid spacing for better F/B and F/R ratios and a bit better gain). Total size is 60" x 60" with the reflector sitting 3.5" behind the driven elements.
» RAW GAIN (dBi): 17.9 to 19.9
» F/B & F/R Ratio: >20 dB (if using 1" x 1" grid)
» SWR: <1.6
View .nec file HERE
nu-Gray Hoverman Quad Stack (470-608 MHz UHF)
This is a horizontal + vertical stack of four nuGH antennas. The GH wire is AWG10 and the reflector wire is AWG16 'hardware cloth' with 2" x 2" grid spacing (use 1" x 1" grid spacing for better F/B and F/R ratios and a bit better gain). Total size is 64" x 70" with the reflector sitting 4" behind the driven elements.
» RAW GAIN (dBi): 18.5 to 20.5
» F/B & F/R Ratio: >20 dB (if using 1" x 1" grid)
» SWR: <1.8
View .nec file HERE
nu-FF6 Flat (470-608 MHz UHF)
This is a version of the nu-FF6 (no reflector) by holl_ands where I added a flat reflector. This design is interesting in that it has >16 dBi of raw gain across the entire new-UHF band (470-608 MHz). The FF6 wire is AWG10 and the reflector wire is AWG16 'hardware cloth' with 1" x 1" grid spacing (only the outline is shown below). Total size is 36" x 68" with the reflector sitting 6" behind the driven elements.
» RAW GAIN (dBi): 16.1 to 16.9 to 16.4
» F/B & F/R Ratio: >21 dB
» SWR: <1.9
View .nec file HERE
Narrow Gray Hoverman + nu-FF6 Flat Combo (174-216 MHz VHF-HI, 470-608 MHz UHF)
This mashup of two different antenna designs by nikiml (Narrow GH) and holl_ands (FF6) is my attempt at a combo antenna for VHF-HI and UHF. But this isn't quite a combo antenna because both VHF and UHF sections require their own balun. So, this design is actually two antennas that share a reflector and it's up to you if you want to combine the signals or not (with a diplexer or dual-input preamp, etc.). The GH and FF6 wires are AWG10 and the reflector wires are AWG16 'hardware cloth' with 2" x 2" grid spacing (only the outlines are shown below). Total size is 70" x 68" with the reflectors sitting 4.5" behind the FF6 and between 10" and 15" behind the GH.
The results of this design were better than I thought they'd be. The coloured numbers in inches on the graphs below refer to the distance between the reflectors and the GH elements (the distance between the reflectors and the FF6 remains fixed at 4.5"). The reflector was split into three sections to improve UHF performance.
» VHF-HI RAW GAIN (dBi): low of 6, high of 12 (depending on dimensions)
» UHF RAW GAIN (dBi): low of 14.2, high of 17.6 (depending on dimensions)
» VHF-HI SWR: low of <1.4, high of <2.8 (depending on dimensions)
» UHF SWR: low of <2.0, high of <2.4 (depending on dimensions)
View .nec file HERE
Single-Extended Hoverman (470-608 MHz UHF)
This is a version of the Extended Hoverman by jed with only one extra GH zigzag instead of two. I used nikiml's optimizer script to design the GH elements and then added a reflector. The elevation pattern is very narrow. The GH wire is AWG10 and the reflector wire is AWG16 'hardware cloth' with 1" x 1" grid spacing (only the outline is shown below). Total size is 36" x 84" with the reflector sitting 4.25" behind the active elements.
» RAW GAIN (dBi): 15.5 to 17.5 to 15.1
» F/B & F/R Ratio: >20 dB
» SWR: <1.8
View .nec file HERE
