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Old February 1st 06, 02:45 AM posted to rec.radio.cb
Jim Hampton
 
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Default some attenna the issue I am interestedin is Bandwidth of the anttena


"Frank Gilliland" wrote in message
...
On Sun, 29 Jan 2006 15:25:34 -0500, wrote in
:

with the report and order on the horizion in the Ham I looking to
assemble a antenna to cover ham 12 across ham ten 10m band meaning it
also sweeps up CB stuff



Depends on what kind of antenna you want. A non-resonant antenna
doesn't care what freq you feed it, but don't look for efficiency in a
small package. A good non-resonant antenna would be a discone, but
were talking a pretty good sized gizmo floating above your yard. At
least the birds would love it.

If you're thinking a 1/2-wave dipole, there are a couple tricks you
can try. A folded dipole has a much greater bandwidth than a standard
dipole. You can get the same effect with a standard dipole by using a
bandwidth compensation tank (an LC tank at the feedpoint and tuned to
the center of the desired bandwidth). It works kinda like a passive
auto-tuner over a limited range. I don't think either method will
cover 12 to 10m, but at least it's a place for an experimenter to
start. I would suggest the tank and play with the Q values.


any advice (asking hams of in antenna is good way to learn about
politic not antennas



No kidding.



Hello, Frank

One could always go with a log-periodic array.

Or a very short, very fat vertical.

Or a Heathkit Cantenna. *Very* low noise pick-up ))



73 from Rochester, NY
Jim