Blair,
You've gotten some good inputs on your question. Vertical polarization
is definitely the way to go on 160m. Given your space constraints, the
K2KQ "Double-L", would be a good antenna for you. See
http://www.yccc.org/Articles/double_l.htm and
http://www.yccc.org/Articles/Antennas/K2KQ/DBL-L.PPT K2KQ shows a dual
band (80-160) version, but you can just leave off the 80m wires if that
band isn't of interest. If you can't get the full height, you can
lengthen the horizontal wires to keep the total length the same. The
impedance will be a bit lower with less vertical height.
N0HR has done some modeling of this antenna and includes radiation
patterns: http://www.n0hr.com/160m%20and%2080m%20Double%20L.htm
This antenna has a lot of low angle signal, but also fills in the null
somewhat at high angles, making it good for short haul work, too. It
will have a lot more bandwidth than an approach using loading coils and
much more efficient than a low dipole.
73, Terry N6RY
On 2009-12-04 5:10 AM, Blair S Balden NP2F wrote:
> I'm getting set to put up a wire dipole for 160 meters. I'm considering 2
> options, and I wanted to hear which one you guys think might be better. The
> feed point will be about 38 feet up on the side of a tower near the house.
> From there, I have just enough room to stretch out a full quarter wave to the
> back edge of my property, where I can get about 25 - 30 feet of height in a
> tree at the other end. So this leg of the dipole will be pretty much
> horizontal.
>
> For the other leg, I don't have that much room. I will need to put in a
> loading coil. I have about 60 feet to a tree in the front yard, where I can
> get about 25 feet of height. This is what I was planning, but I also thought
> about bringing that leg straight down from the feed point. In that case, the
> antenna would have one full-length horizontal leg and one short (about 30
> foot) vertical leg with a loading coil.
>
> Do you think anything would be gained by having part of the antenna vertical?
> Would I get some lower-angle radiation if I did it that way? Or would it
> work better more or less horizontal?
>
>
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