On 24 Oct 2003 at 6:37, David Knepper wrote:
> My goal is to work DX on 160 meters, that is, having the capability to work
> at least to the westcoast from Pennsylvania and Europe when the band is
> open. I am asking the lists opinion on on my three options:
>
> 1. Full-Wave vertical loop - what should be the configuration?
> 2. 1/2 wave dipole
> 3. Inverted L
>
> If there is not a great deal of difference, I may just put up a dipole and
> wait until next year when I get the 100 foot tower erected and use it as a
> vertical on topband.
>
> Incidentally, I am using high trees for supports.
>
> Are there other wire antenna choices?
>
> Short answer would be appreciated.
> Thank you for your time and expertise.
>
> Dave, W3ST
>
Hi, Dave-
I hope you take the time to research it all, and get
the benefit of all the collective wisdom on this reflector.
Sounds to me like an inverted L would be your best bet.
I am guessing that your "high trees" might not yield a lot
more than 70 feet of practical antenna height. I also have
'tall' trees on my lot, many of them topping out at 120-130
feet- and yet about 70 to 80 feet tops has been the most
elevation 'boost' I have been able to get.
If you do put up an inverted L, it is important to work it
against a massive radial field. You really do need to lay
down as many radial wires as you possibly can.
Research the reflector archives for a lot of advanced tips
about how many/ how long, etc.
My personal choice for top band has been a full size
vertical loop, with about 1/2 aloft and the other 1/2
running above the ground as high as I could get it
(15-20 feet above ground). I think it is past time that I
write up my personal experiences with that loop and
add it as another page on my website. When I have it
done, I will post another note to the reflector with the
url. For now, I might mention that the antenna must
work pretty good, as I received email comments from
S9SS (formerly S92SS) that I would have to have been
one of the stronger east coast US stations to have
earned a QSL from S92SS on 160m, as his noise level
over there has been horrendous. I might also add that
I was very pleased and surprised to learn that my full
size loop had an acceptably low SWR across the
entire 200KHz of band- and more, if you count the
low SWR part of the curve that extends down into the
broadcast band. This wide SWR may be due to
antenna losses, however, and may be more apparent
than 'real'. And it all depends, as well, on what you
consider 'acceptable' for SWR. My tube power amps
have little trouble working at/above 2:1 SWR on 160m.
73, David K3KY
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