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 holl_ands | Home > Circular Polarized incl. Rabbit-Ears > Simple "VEE" Rabbit Ears > 
VHF Simple-VEE-Rabbit-Ears
VHF Simple-VEE-Rabbit-Ears (no matching network) analyzed using 4nec2.

Hi-VHF Band Optimum Whisker Length = 14.75 for Quarter-Inch-Copper-Tubing (QICT) with Feedpoint Gap = 0.75-in.

For 45-degree Angle, Horizontal Polarization Gain was equal to Vertical Polarization Gain across Hi-VHF Band.

Note: Even a 0.5-inch error in lengths of Rabbit Ears severely degraded SWR, although only minor impact on Raw Gain.

EDIT (10Sep2011): Added a "What-IF" exercise to illustrate the Raw Gain and SWR (if 300-ohms) from Ch2-13.
Note that SWR in Hi-VHF Band is four time higher than for 75-ohms, and becomes even more excessive
on lower freqs, as the Impedance becomes nearly all Capacitance (negative Reactance).

EDIT (16Jan2012): Added Circular Polarization Azimuthal Plots.  Note that Right Circular = Left Circular
at 90-deg & 270-deg Azimuths, so there is very little suppression of Cross-Polarized (e.g. reflected Multipath) signals.

ERRATA (5Sep2014): Uploaded revised 4nec2 File with sin and cos functions reversed to match
Angle Definition in Comment description.  Since all charts were for 45-degree Angle, they are NOT affected.
Date(s): 14 Feb 2011. Album by holl_ands. 1 - 24 of 24 Total. 3188 Visits.
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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
3D View


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
Front View
[1 small box = 0.5 inch]


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DOC3
Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
4nec2 File


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
Total Raw Gain on Ch7-13


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
SWR (75-ohms) on Ch7-13


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
Impedance on Ch7-13


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
Total, Horiz. & Vert. Patterns at 174 MHz


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
Total, Horiz. & Vert. Patterns at 198 MHz


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Hi-VHF Simple-Rabbit-Ears, WL=14.75", Gap=0.75", Angle=45-deg
Total, Horiz. & Vert. Patterns at 216 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 54 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 66 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 78 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 90 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 102 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 174 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 198 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns at 216 MHz


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VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Circular Polarization Patterns - Ani-Gif

Right = Left Circular Polarization
at 90-deg & 270-deg.


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Hi-VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
3D Total Gain Pattern at 198 MHz


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Hi-VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
3D Horizontal Polarization Gain at 198 MHz


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Hi-VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
3D Vertical Gain Pattern at 198 MHz


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Hi-VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Total Raw Gain on Ch2-13


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Hi-VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
SWR (300-ohms) on Ch2-13


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Hi-VHF Simple-Rabbit-Ears
WL=14.75", Gap=0.75", Angle=45-deg
Impedance on Ch2-13


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