Hi Todd,
In my opinion you're giving up too easily on your tall antenna.
I suggest that you focus more on evaluating its on-the-air performance ,
and not focus as intently its feed point impedance and VSWR bandwidth.
I hope you've been measuring the impedance and bandwidth
of your tall antenna with your 43 foot vertical disconnecte d from
its both its 160 meter matching components and its feed line,
otherwise it will interact very strongly with your tall antenna.
Very few of us have the opportunity to install our 160 meter
antennas a thousand feet or more from other antennas and tall
towers. As a result, the feed point impedance and other characteristics
of our antennas can't possibly match theoretical values. Nonetheless,
we enjoy our imperfect antennas with their imperfect soil conditions.
I hope you'll enjoy yours too.
73
Frank
W3LPL
----- Original Message -----
From: "Todd Goins" <tgoins@gmail.com>
To: topband@contesting.com, 676a8e87-aec6-9ead-1297-0bdb1f0a7071@gmail.com
Sent: Wednesday, January 23, 2019 9:09:19 PM
Subject: Re: Topband: Inverted L improvements - Part 3 (now with data)
Both Merv and Guy are correct here. Perhaps this antenna doesn't ever
have a chance at being any good due to the suburban area and lot size
that I'm constrained by.
Within a 250ft radius (huge!) there is as follows: 80m dipole, 40m
dipole, 30m dipole, 20m dipole, 15m dipole, 20m yagi, and the original
43' tall T antenna for 160m and its radial system. Also, the house is
easily within 250ft. Most certainly the radial systems, although not
physically connected to each other, are let's say "mingling".
So perhaps this tall wire was doomed from the outset? I was so
encouraged that the 43' T worked so well for what it was and the small
amount of effort it took to get converted to 160m that maybe a taller
version would be substantially better. That's how this saga started.
Maybe the real answer after time/effort/money expended and all of your
advise is that it isn't going to get any better in my environment?
At this point the best path forward may be to just remove the tall
wire and reroute all of the new radials (over 2000ft) to the original
43' T's radial plate and with any luck make it play better as a
result?
Todd - NR7RR
>Way back some where around the original posting did he not say he had
>2 160 antennas up and they are close to each other? a short vertical and
>this antenna? If so what is the short vertical doing, is it floating or
>grounded or hooked to the ground system yet, what is its status?
>Would make all the difference in the world if the short 160 vertical is
>any where around yet.
>
>73 Merv K9FD
>* Have to pay attention to everything he is reporting. He added a feedpoint
*>* choke per K9YC at the same time. Which may, depending on the physical
*>* connections at his feedpoint, have removed the feedline shield as an
*>* alternate “radial” in parallel with the increasing but still not full size
*>* radial system.
*>>* That indicates that his ground characteristics could be well into the
*>* “poor” end of the range where ground radial deficiencies are multiplied and
*>* emphasized.
*>>* His SWR bandwidth narrowed slightly. Leaving a strong possibility that
*>* there was an improvement in desired radiated pattern.
*>>* There remains the question of every conductor in a 250 foot radius,
*>* including a tower? There remains the question of large dielectric masses
*>* close by.
*>>* 73, Guy K2AV
*
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