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2m "Classic" 3QWL+QWL J-Pole
2-meter "Classic" J-Pole with L1=3/4 and L2=1/4 Wavelength analyzed using 4nec2.
Analysis for other L1, L2 Lengths to be provided in a separate Album.

Includes PARAMETRIC SWEEP Analysis to investigate Performance as Feedpoint Height
is varied and also as L1-L2 Separation is varied.
6 Mar 201827 items1585 visitsAlbum by holl_ands
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2m "Classic" 3QWL+QWL J-Pole
3D View
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2m "Classic" 3QWL+QWL J-Pole
Side View
[1 large square = 5-inches]
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2m "Classic" 3QWL+QWL J-Pole
4nec2 File, includes Dimensions
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2m "Classic" 3QWL+QWL J-Pole
144-148 MHz Raw Gain = 3.0 to 3.1 dBi
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2m "Classic" 3QWL+QWL J-Pole
144-148 MHz SWR(50-ohm) = 1.4 to 1.7
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2m "Classic" 3QWL+QWL J-Pole
144-148 MHz Impedance
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2m "Classic" 3QWL+QWL J-Pole
Azimuthal Pattern at 130 MHz
130 MHz F/B = 1.3 dB

Not Quite a True OMNI
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2m "Classic" 3QWL+QWL J-Pole
Azimuthal Pattern at 146 MHz
146 MHz F/B = 1.3 dB

Not Quite a True OMNI
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2m "Classic" 3QWL+QWL J-Pole
Azimuthal Pattern at 160 MHz
160 MHz F/B = 0.7 dB

Not Quite a True OMNI
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2m "Classic" 3QWL+QWL J-Pole
Elevation Pattern at 130 MHz
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2m "Classic" 3QWL+QWL J-Pole
Elevation Pattern at 146 MHz
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2m "Classic" 3QWL+QWL J-Pole
Elevation Pattern at 160 MHz
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2m "Classic" 3QWL+QWL J-Pole
420-450 MHz Raw Gain ~ 0 dBi
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2m "Classic" 3QWL+QWL J-Pole
420-450 MHz SWR(50-ohms) is Too High
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2m "Classic" 3QWL+QWL J-Pole
420-450 MHz Impedance
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2m "Classic" 3QWL+QWL J-Pole
Azimuthal Pattern at 400 MHz

Significant Gain Loss to the Rear
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2m "Classic" 3QWL+QWL J-Pole
Azimuthal Pattern at 440 MHz

Not Quite True Omni
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2m "Classic" 3QWL+QWL J-Pole
Azimuthal Pattern at 470 MHz

Moderate Forward Gain Loss
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2m "Classic" 3QWL+QWL J-Pole
Elevation Pattern at 400 MHz

Significant Gain Loss
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2m "Classic" 3QWL+QWL J-Pole
Elevation Pattern at 440 MHz

Significant Gain Loss
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2m "Classic" 3QWL+QWL J-Pole
Elevation Pattern at 470 MHz

Significant Gain Loss
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2m "Classic" 3QWL+QWL J-Pole
146 MHz Raw Gain ~ 3.0 dBi
for Sep = 2 to 16 inches

Raw Gain drops off less than 3.0 dBi for
Sep above 18 and NULL near 40 inches
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2m "Classic" 3QWL+QWL J-Pole
146 MHz F/R Ratio = 1.5 to 5.7
For Sep = 2 to 22 inches

Closest to "True Omni" for small Sep
Highest F/R near Sep = 16.5 inches
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2m "Classic" 3QWL+QWL J-Pole
146 MHz SWR(50-ohms) Under 2.7
for S12 = 2 to 6 inches

Increase L1 to L2 Separation for
higher Characteristic Impedance
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2m "Classic" 3QWL+QWL J-Pole
146 MHz Raw Gain 2.2 to 2.3 dBi
For Hfeed = 1 to 18

Raw Gain roughly CONSTANT as vary Feedpoint Height.
A Bit Closer to True Omni as INCREASE Hfeed.
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2m "Classic" 3QWL+QWL J-Pole
146 MHz SWR(50-ohms) Under 2.0
for Sep = 2.5 to 4.5 inches

For Higher Characteristic Impedance
simply increase Hfeed.
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2m "Classic" 3QWL+QWL J-Pole
146 MHz Impedance
for Hfeed = 1 to 19 inches
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