On Wed, 08 Jun 2005 14:16:06 -0700, Wes Stewart
wrote:
On Wed, 08 Jun 2005 12:23:50 -0700, Wes Stewart
wrote:
[snip}
Under "Qualifier" scroll the dropdown menu to either "Generic 450 ohm
window" or if you more more realistic numbers you can select one of
the Wireman Ladder line types. (Ignore "wet" ones.)
This should of course read, "...if you want more realistic..."
I am not sure what I just did or saw. I had several colored graphs
charted and one gray. The gray didn't seem to move around, but the
colored ones sure did. I am afraid I didn't see what you were trying
to show me. I believe the colors were the different feed lines,
capacitors, etc used in the feedline shown. I tried removing them and
only leaving the feedline I chose to use. I don't know if I did
something wrong or not, but the gray line appeared to be the antenna
and it never appeared to move. The feedline markers moved radically.
I haven't thought a lot about the losses in ladder-type feedline, but
I do understand how the losses in coax can reduce High SWR by reducing
both the outgoing and incoming reflected signals in the coax. This
may make the antenna desirable to the rig, but it doesn't do any good
for the operator who is trying to reach or copy that weak signal. It
may well be that the Twin-lead has the same effect. I often read that
one of the advantages of the twin-lead is that it can handle higher
SWR without the higher losses of coax.
I seem to have been seeing a lot about the technology of the twin-lead
tuning technology, but then I can't be sure it wasn't from the same
people here on this forum. I'll continue to look into it to see what
I might learn.
I was able to get past whatever block I had on learning to use EZNEC,
so at least some good came from this discussion. Hopefully, I'll
learn more and can model this antenna and others I read about.
Thanks very much for taking the time to address this with me.
73,
Buck
N4PGW
--
73 for now
Buck
N4PGW
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