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Old March 6th 07, 12:37 AM posted to rec.radio.amateur.antenna
Jim Lux Jim Lux is offline
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First recorded activity by RadioBanter: Mar 2007
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Default radiation pattern of log-periodic antenna

Roy Lewallen wrote:
Frank wrote:

. . . NEC source code is available
in FORTRAN, so you could translate it to C.



It was done long ago. See
http://www.nic.funet.fi/pub/ham/ante...C/swindex.html for sources. A
google search might reveal others.

Roy Lewallen, W7EL


A simpler approach, depending on the accuracy needed, might be to
convert some matlab codes. Orfanidis's book has matlab routines to do
the mutual coupling calculations and the transmission lines and to
generate a radiation pattern from the element currents. heck, he might
even have a LPDA model in there.. it would be a good exercise for a
class on computational electromagnetics. If it's a free space model,
that might be the easiest.

I have heard, but do not know from my own experience or anyone I know
(essentialy it is totally unsubstantiated rumor), that the NEC
repository C code version of NEC (converted by something like f2c) has a
number of problems. Given the age of the original FORTRAN code and its
coding style, I can believe that a machine translation might introduce
artifacts.