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Hi-VHF 14-El LPDA
Hi-VHF Band, 14-Element LPDA (Log Periodic Dipole Array), 100-inch boom with zig-zag feed.
Geometry and beginning NEC file from ZS6BTE's "Wideband Antennas for TV DXer".  (No longer available on QSL.NET)
Element lengths and spacings SAME as following Zig-Zags.  Excellent match to 75-ohm load, using a 1:1 Balun (NOT the usual 4:1).
Date(s): 24 Dec 2008. Album by holl_ands. 1 - 10 of 10 Total. 4671 Visits.
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3D/Top View - Hi-VHF 14-Element LPDA (fm ZS6BTE).

Note zig-zag feedline vice dual boom alternative.
NEC simulates this using TL Card.

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Sweep wire radius size (Radius).
Only minimal improvement above AWG14 (Radius=0.03).

Smaller wire sizes primarily degrade F/B Ratio.

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LPDA 14-Element - zig-zag feed - QICT
(Quarter Inch O.D. Copper Tubing)
Average Gain Test = 0.9974

Click image to see hi-rez versions.
Click "X", as usual, to exit window.

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LPDA 14-Elements, zig-zag feeder - QICT

Excellent 10 to 10.25 dBi Gain vs Frequency.

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LPDA 14-Elements, zig-zag feeder - QICT
Excellent SWR vs Frequency.

Hi-VHF Band is 174 to 216 MHz.

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LPDA 14-Elements, zig-zag feeder - QICT
Impedance vs Frequency.
It's a 75-ohm antenna, which uses a 1:1 Balun.

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LPDA 14-Elements, zig-zag feeder
If Element Radius same as RG-59 Braid.

Excellent Gain = 9.9 to 10.8 dBi

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LPDA 14-Elements, zig-zag feeder
If Element Radius same as RG-59 Braid.

Excellent SWR under 1.12

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LPDA 14-Elements, zig-zag feeder
If Element Radius same as RG-59 Braid.

Impedance vs Frequency

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4nec2 File: Hi-VHF Band, 14-Element LPDA.
With 100-inch Boom and Zig-Zag Feed.

 
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