DX season on 160 Meters (Amateur Band)

Discussion about Medium Wave and 160-meter propagation.

DX season on 160 Meters (Amateur Band)

Postby NW7US » Sat Oct 18, 2003 3:30 am

We're well into the fall months. The geomagnetic field will steadily quiet down as we move away from the autumnal equinox. Shorter daylight hours cause a reduction in D layer ionization. That makes for the right conditions for propagation of signals in the 160 meter band (1800 kHz to 2000 kHz).

How's DX? What are you hearing? What sort of station are you running? What antenna systems do you have in place for 160?
73, de NW7US (Tomas David Hood)
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Postby ku4a » Mon Oct 20, 2003 1:27 pm

I haven't done anything on 160m yet this season. The only antenna I have for that band is an 80-meter quarter-wave sloper that can be loaded on 160 with a tuner. It is strictly a high-angle/low-efficiency arrangement :). I get surprizingly good reports, but my best "DX" is generally only out to 1000 miles or so.
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Struggling on 160

Postby k3xo » Mon Oct 25, 2004 9:36 pm

I finally have some room to put up an antenna for 160 so I thought I would give it a try.

I'm running 100 watts and I started with a double-size G5RV and managed a couple of contacts in 8- and 9-land, and the other night worked NP4A. But overall, I did not feel I was getting much with the antenna. I kept seeing 160 meter spots and hearing stations within several hundred miles of me working Europeans, but I could not hear the EU stations at all!

So over the weekend, I took down the G5RV and put up a full-size dipole. One problem, I am sure, is that it is barely 30 feet high and one end slopes down to about 10 feet at the end. That is as high as I can get with the trees I have available.

After putting the new antenna up, I worked FP/VE7SV early and heard FM5BH later on, but I am still not hearing Europeans.

So the question is, will conditions improve so I will have a chance to pick up a few EU multipliers in the CQWW at least on CW or is my antenna still just not good enough for anything beyond the NA continental borders?

Thanks for any thoughts you can share.

73 Rip K3XO
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Postby ku4a » Tue Oct 26, 2004 5:44 pm

While nothing is impossible, I would say your antenna has too high a radiation angle to be good for DX such as Europe.

You have two possibilities:

(1) A horizontal antenna for 160 such as a dipole would have to be extremely high to have a low radiation angle. Thirty feet is not even close to being high enough.

(2) A vertical antenna is a low radiation angle antenna to begin with, so they are quite common among 160m DXers. The problem here is that vertical efficiency declines as the length falls below 1/4 wavelength. A "full sized" vertical for 160 would have to be about 120 feet high or so. Any smaller, and efficiency falls. Also, for ground mounted verticals, there is the issue of ground radials which you will need a lot of to be efficient.

Let me point out that I am no expert on 160. I have so little space that I am lucky to be able to have any antenna that even loads up well on 160, let alone work great stuff. I get on 160 maybe once or twice a year, and typically only work stations within 1000 miles or so of my QTH.

Perhaps someone with a bit more experience on the band can give you some better ideas.

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Postby n6hb » Tue Dec 28, 2004 4:37 am

ku4a wrote:While nothing is impossible, I would say your antenna has too high a radiation angle to be good for DX such as Europe.

[. . .]

Perhaps someone with a bit more experience on the band can give you some better ideas.
I'm not an expert either, but I think your comments are right on the mark. Prior to this contest season, I was the 160 op at KC1XX. I also operated with a fair degree of success back when I lived in New England (as KA1XN).

A 30' high horizontal antenna, especially given the over-land path from K3XO in WV, is going to have too much path loss to make it into Europe under most normal propogation conditions. A top-loaded vertical or W9INN sloper might be excellent choices to try when limited by real estate or geography. Either way, concentrate on building an excellent ground system.
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Postby AmericanDXer » Thu Aug 03, 2006 10:21 pm

I rarely hear people on 160 meters here, seems like a high noise floor is the problem most of the time. My dipole is up on the roof about 35-40ft off the ground. I hear a lot of Hams from differant countries on the 40m and 20m bands, but never the 160m band. The only ones I've heard on 160 were from the upper midwest.
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Postby ku4a » Fri Aug 04, 2006 2:08 pm

Yes, your antenna is too short and too low to do much with that band. You are hearing a bit of high-angle stuff which is typical of short, low antennas on 160.
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Postby AmericanDXer » Sat Aug 05, 2006 12:00 am

Yeah, but its 66ft long total. You would think I would be able to hear a little more down there, and the antenna is up and in the clear too...but then again I don't do much listening on 160meters anyway.
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Postby ku4a » Wed Aug 16, 2006 2:27 pm

What is important is the length relative to the wavelength, and the height above ground relative to the wavelength.

At the higher frequencies (shorter wavelengths) your antenna is a reasonable length, and at a reasonable height. Height above ground determines radiation angle (also the angle at which you can receive signals).

As you go down in frequency (longer wavelengths), your antenna is becoming less efficient, and the radiation angle is becoming higher. Therefore, you are only hearing loud signals from nearby.

Continue to let me know any questions you might have about antennas.
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Postby AmericanDXer » Sat Aug 19, 2006 5:20 pm

The other night, I heard a lot of 160 from all over the country!!!!

It was really good DX, but still...
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