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KK4OBI Bent Dipoles


This is the 4NEC2 antenna bend model for: Zeppelin Stub horizontal
To use this model:
4NEC2 is an NEC2, NEC4, Windows based antenna modeler and optimizer by Arie Voors.
It is available free of charge at: www.qsl.net/4nec2/


CM This is a Zeppelin type antenna with stub tuning where the 1/4-wave matching section is fed at the middle of the closed end.
CM To do this the 1/4-wave wires are shortened by half the separation distance. 
CM Procedure 1st:  Set higher Frequency. Set X ~ 1/2 wave. Set A~ 1/4 wave.  Set Stub = 0.1   Optimize (F12) lengths X and A..
CM Procedure 2nd:  Set lower Frequency.  Optimize (F12) Stub
CE
SY freq=14.2    '14.2    7.2
SY hgh=65    'feet  1/2 wave 469/freq
SY sep=1
SY X=33.92424    '1/2 wave long wire
SY A=17.24027    '1/4 wave short wire
SY Acf=A-sep/2    'Short wire minus half separation
SY Stub=6.74027    'Tuning stub  @ 2.71 SWR
SY Embeded Calcs=2
SY Longwire=X+Acf+stub    'The long straight wire
SY TotWire=Longwire+sep+Acf    'The total wire
GW    1    145    Acf    0    hgh    Acf+X    0    hgh    #14    '1/2 wave
GW    2    75    0    0    hgh    Acf    0    hgh    #14    'Lower 1/4 wave
GW    3    3    0    0    hgh    0    0    hgh+sep    #14    'Separation
GW    4    75    0    0    hgh+sep    Acf    0    hgh+sep    #14    'Upper 1/4 wave
GW    5    31    0    0    hgh    -stub    0    hgh    #14    'Tuning stub
GS    0    0    0.3048
GE    1
GN    2    0    0    0    14    6.e-3
EK
EX    0    3    50%    0    1    0    0
FR    0    0    0    0    Freq    0
EN

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