This is the 4NEC2 antenna bend model for: Off-Center-Feed (OCF) Impedance
To use this model:
Below. Highlight and copy (Ctrl C) the program control codes (CM,
Open Windows Wordpad and copy (Ctrl V) the control codes into Wordpad.
Go to "File, Save as..." and name your new antenna model.
In Windows Explorer, right-click on your new model and "Rename" the file to end as ".nec".
Open your new model to find the impedance of a dipole fed at
various feedpoints (R=).
4NEC2 is an NEC2, NEC4, Windows based antenna modeler and optimizer by
It is available free of charge at: www.qsl.net/4nec2/
CM Standardized model for OCF
feedpoint impedance study
CM #14 AWG. 1/2 wavelength feedpoint over ground at 28.4 mc.
CM Velocity factor to hit target frequency
CM Variable Off-Center feed ratio.
CM Dick Reid, KK4OBI, 2016
feedpoint height - meters
center ratio. 0.5=center feedpoint
'Optimized #14 AWG velocity factor to hit frequency target
'ratio arm length - meters
SY oth=150/F*(1-R)*vel 'other arm length - meters
GW 2 25
-L 0 hgh
0 0 hgh
#14 'ratio arm
GW 3 25
0 0 hgh
oth 0 hgh
#14 'other arm
GN 2 0
0 0 14 6.e-3
EX 0 2
25 0 1
EX 0 3
1 0 1
FR 0 0
0 0 28.4 0