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CM-4251 Parabolic+FBmod+8-El LPDA
CM4251 Parabolic Reflector with 4-Wires added to Reflector (FBmod) and 8-Element LPDA
(Log Periodic Dipole Array) Feed analyzed using 4nec2.

CM4251 2-Bay Feed is replaced by 8-Element LPDA, see fol. analysis, which was fabricated by oldsparks:
http://www.qsl.net/va3rr/hdtv/HDTV.htm
GHZ24 offset & reversed the LPDA for insertion into a Parabolic Reflector 4nec2 File:
http://ghz24.freeshell.org/antenna/models/newermodels/parabolas/feeds/lpda8.nec

Note glitches near 698 MHz for Raw Gain, F/B and F/R Ratios.  Although probably not large enough to cause
problems, this can be cured by adding a shorting stub.
Date(s): 24 May 2013. Album by holl_ands. 1 - 9 of 9 Total. 4941 Visits.
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CM-4251 Parabolic+FBmod+8-El LPDA
Comparison Chart: Various x = Separation
from Parabolic Reflector to Smallest LPDA Element


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CM-4251 Parabolic+FBmod+8-El LPDA
3D View


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CM-4251 Parabolic+FBmod+8-El LPDA
Front View
[1 large box = 12.5 inches]


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CM-4251 Parabolic+FBmod+8-El LPDA
Top View
[1 large box = 12.5 inches]


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CM-4251 Parabolic+FBmod+8-El LPDA
Side View
[1 large box = 12.5 inches]


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DOC6
CM-4251 Parabolic+FBmod+8-El LPDA
4nec2 File


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CM-4251 Parabolic+FBmod+8-El LPDA
UHF Raw Gain = 20.2 dBi at 698 MHz


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CM-4251 Parabolic+FBmod+8-El LPDA
UHF SWR (300-ohm) Under 1.6


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CM-4251 Parabolic+FBmod+8-El LPDA
UHF Impedance


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