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Old May 9th 04, 06:41 PM
N8KDV
 
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CW wrote:

Even if you do match it, it will be at only one frequency. At any other, the
mismatch returns.


There are ways to get more of a broadband match, via the use of a matching
transformer.



"-=jd=-" wrote in message
...
I had about 300' of #14 insulated wire strung in this "Z" shape down one
of the woodlines on my property. It really overloaded the receiver, but
with an external attenuator, it was a very useable signal snagger.

Last week, the new wore off and I decided to change it. I now have about
100' of that wire arranged in horizontal triangular loop.

The happy surprise is that the S/N ratio is much, much better.

The one thing that I would like to do is try to figure out the actual
characteristic impedance of the antenna. I've found information that shows
me how to do this with a noise-bridge, but I don't have one of those.

I was wondering if anyone knows of a link or a formula for finding a
relatively close "ballpark" figure for characteristic impedance. I'm
thinking there isn't (without the inclusion of one or more physical
measurements) due to all of the variables involved.

To add to the dificulty, the antenna is over sloping terrain and I recall
that height above terrain affects impedance.

The end goal is to match a coax feed to the antenna as closely as
*reasonably* possible. I understand that there's the distinct possibility
that after going through all the effort to determine what ratio is needed
for the transformer, a SWAG may well have produced the same or similar
results... But, it's a hobby and I have the time.

-=jd=-
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