I wonder.....Is there is a simple way to compare the field strength of an FCP
with my current NON dense and uniform ground system, and draw reasonably
accurate conclusions about efficiency improvements ??....
my suburban lot is small, and i would prefer to make the measurements on my
property; the lot is 120' ( north / south ) x 170' ( east / west )....the
marconi T is essentially centered
10 feet north of the south property line...there is a 'way too big' house
almost centered on the property. the current 45 radials are squeezed into a
20' x 100' space centered 10 ft north of the south property line.
I can build a simple field strength meter easily enough, and use a DMM for 3
digit accuracy. any proposal for its antenna? short whip? short vertical
dipole? small loop? and, should i measure the voltage across a 50 ohm resistor,
or ?? i think i 'know' to use voltages well above the diode's PN junction
threshold. Ideally, I would like to be able to switch back and forth quickly,
but that does not seem likely if a reasonably accurate impedance match is made
with both configurations. I was hoping to do this with local bud K5LC, but we
saw more than 3db variations in a short period of time over the 2 mile path.
the "non-uniform, non-dense" radial field has, historically, been 'fair to
middlin...' 73, w5xz, dan
--- On Sun, 9/23/12, Wes Attaway (N5WA) <wesattaway@bellsouth.net> wrote:
From: Wes Attaway (N5WA) <wesattaway@bellsouth.net>
Subject: Re: Topband: Response to W8JI's comments about using a K2AV
foldedcounterpoise at VK6VZ
To: "'Tom W8JI'" <w8ji@w8ji.com>, topband@contesting.com
Date: Sunday, September 23, 2012, 8:51 PM
I think that as long as we can agree that just because someone thinks a
particular antenna works better than some other antenna they have had, and
no rigorous testing under scientifically controlled conditions has been
done, and that the opinion is just an opinion and nothing more, then we will
all be OK.
Jim is correct that all antennas are some sort of compromise and if you are
happy with an antenna under your particular conditions then that is fine.
Tom is obviously correct in saying that you can't infer much about claims of
performance unless you have some good test data to back up the claims.
A good operator can work more DX with a so-so antenna than a poor operator
can. Does that make the antenna "better" in the good operator's location?
If you are on a much sought after small Pacific atoll with a crappy antenna
you are still going to make more contacts than you would sitting in Caddo
Parish in North Louisiana with the same antenna. Does that make the antenna
"better" than some other antenna out on the island? As Tom points out, the
answer is only determined by serious testing.
Most hams aren't going to go to the time and trouble of doing serious
testing, for a lot of reasons. However, some will do it and the results are
usually enlightening. Serious test results usually reveal a lot of
unexpected results. Then again, when you have to replicate the test results
antenna in some other location you may have a problem, unless you do more
testing at the new location (nearby towers, wires, trees, hills, stone
walls, metal buildings, etc).
As an aside ....One thing I have always told young hams is to just quickly
put up the best antenna you can at the beginning and get on the air. If you
diddle around forever wondering whether this or that antenna will work then
you won't be on the air having some fun.
There is both a technical and a practical side to this whole discussion and
I think Jim and Tom are each worth paying attention to.
----------------- Wes Attaway (N5WA) -------------------
1138 Waters Edge Circle, Shreveport, LA 71106
318-797-4972 (Office) - 318-393-3289 (Cell)
Computer Consulting and Forensics
-------------- EnCase Certified Examiner ---------------
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Tom W8JI
Sent: Sunday, September 23, 2012 4:57 PM
To: topband@contesting.com
Subject: Re: Topband: Response to W8JI's comments about using a K2AV
foldedcounterpoise at VK6VZ
> is a compromise. It's sad that some cannot see that forest for the trees.
> :)
>
> 73, Jim K9YC
Comments like that are expected, but are totally out of place in technical
discussions. No one said the antenna does not work or cannot work, only that
some of the claims obviously reach far beyond what can be determined.
An experiment without some reasonable reality check isn't advancing the
state of art, it is advancing the state of graffiti.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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