Allen, I totally agree with most of what you are saying. I have put up
many dipoles, verticals etc but this is my first windom antenna. No, it
does not use traps and it is an off center fed dipole with a 4 to 1 balun.
It is 136 feet long and long leg is 92 feet and short leg is 44 feet. I
will wait to see what others say before making any more comments as this is
my first windom and I may not know what I am talking about.I just got the
antenna up so I haven't had time to do much with it. I won't be able to do
anything much this week as we are having our bathrooms remodeled and things
will be in a mess. Thanks much,
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Alan R. Downing
Sent: Sunday, August 04, 2013 6:48 AM
To: [log in to unmask]
Subject: Re: Update on 80 meter windom antenna
Hello Fred,
I am not familiar with this antenna, but if the lowest SWR that you can
achieve is 2.0 to 1, then I would suggest that something is very wrong. I
have read specs on many multi-band antennas over the years, and the highest
SWR at band edges is generally stated to be under 2.0 to 1. An SWR of 6.0
to 1 is outrageous in my opinion. You may use a tuner to bring the SWR
down, but that doesn't do anything to reduce the SWR from the perspective
of the coax. If you ran very much power into an antenna with an SWR of 6
to 1 you would probably destroy the coax. Many hams believe that
everything is hunkey dorey when the tuner brings the SWR down from the
perspective of the radio, but that doesn't mean that the coax won't suffer
the consequences. A tuner does not reduce the SWR on the feed line. Have
you reviewed the assembly or installation directions that came with the
antenna to see what is said regarding tuning the antenna? The paperwork
may tell you how to reduce the SWR, without destroying the SWR on any
single band. Does this antenna use traps? Also, what kind of coax are you
using? What is the maximum power that you will be transmitting? Perhaps
others will express their opinions about this SWR situation, but I
personally would not use an antenna with SWR over 2.0 to 1. I go crazy if
my SteppIr displays an SWR at some frequency on the band of 1.2 to 1. I am
not saying that every antenna will have an SWR as low as what a SteppIr
will produce, but I believe that the installation and operating
instructions for my DB36 say that an SWR
under 1.5 to 1 is acceptable. That means that an SWR at that point on the
band in question over 1.5 to 1 is unacceptable, and that further tuning on
that band is required.
If the antenna instructions that a balun is required, then get an
appropriate one before pouring on the coal.
Best 73, and good luck.
Alan R. Downing
Phoenix, AZ
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Fred Adams
Sent: Sunday, August 04, 2013 3:01 AM
To: [log in to unmask]
Subject: Update on 80 meter windom antenna
I think you guys remember me asking for info on the 10 thru 80 meter windom
antenna a couple of weeks ago and I thought I would bring you up to date on
my progress. I purchased the antenna from Radio WAVZ and got it up on my
tower about 6 PM Friday evening so I haven't had time for lots of testing.
I had just enough room to put it up without any bends or turns. The apex
is up at about 37 feet and the ends up at 10 feet. I had enough COAX to
make only a 3 turns choke with adding extra COAX and so far I have had no
RF. I can tune allbands with my LDG tuner except 15 meters. I do not need
a tuner on the 40 meter band and I didn't try 60 meters as I couldn't
remember the frequencies. The highest SWR is on 75 meters and I would like
to bring it down some if possible. On 75 meters the SWR is 6.0 and the
other bands run from 2.0 to just over 3.0.The low end of 75 meters is about
3.5 SWR.I do not want to make any quick changes as I suspect making any
changes may change the other bands also. Band reception has not been very
good but as best I can tell the antenna seems to receive well. It sure is
nice to get most of the bands with a single dipole antenna. I will
appreciate any suggestions for improvement and especially bringing down the
SWR on 75 meters. Thanks much,
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