[TowerTalk] 160M Wire Antenna

[Tom Rauch]

Hi All,

W2EQS was one of the very first 160 meter DXCC holders, and he 
used a dipole at 50 feet or less and only 100 watts. Operator skill 
and determination is 90% of a good country total. The country total 
certainly does not indicate the system is optimal, it just means it 
is possible to work DX.

I can put actual performance numbers on this subject from real-
world tests. 

I've made hundreds and hundreds of A-B-C tests with DX stations 
and many with local stations on 160 meters. In the tests, I've 
compared dipoles at 300+ feet, dipoles at 80 or 160 feet, and a 
vertical with a good ground system (a 200 foot tower with one 
hundred 200 foot long radials).   

> According to the table in the antenna book, even for the 60-foot high
> dipole, the signal at 25 degrees above the horizon is only 6 dB down from
> the straight-up maximum.  So if you can hear 'em, you probably can work
> 'em.

I believe the wave angle on 160 meters is much lower than people 
assume.

With VK/ZL:

I gathered about 800 reports over a one year period with VK3ZL and 
ZL3REX starting just before their sunset and continuing to my 
sunrise and beyond. (Out of a year there were only about a dozen 
days when we could not work on 160 meters!) 

My 200 foot vertical is better than my 300 ft high dipole by as much 
as 20 dB and no less than 3 dB 95% of the time, if all times we 
could work are included. 

If only sunrise peaks are considered, the high dipole is about even 
with the 200 ft vertical. 

The low dipoles are ALWAYS at least 6 dB weaker than the 
vertical and often 25 dB or more weaker... except on rare exception 
days when signals are just booming in (generally during or just 
after geomagnetic storms). During those rare times, all of the 
antennas are about even.

The only time the high horizontals play well on a regular basis is 
during a short time interval at sunrise during the peak on certain 
days...especially during geomagnetic disturbances. The low 
horizontal, while it does produce contacts, is a dog compared to 
the other antennas for long DX.  

Into Europe:

The high horizontal (I had one broadside on Europe at one time) 
was only better on two days out of a year of trying! Most of the 
time the high horizontal was about an 5 to 10 dB weaker, on 
occasion during good conditions it would be about equal to the 
vertical but with much more fading. The low horizontals were 
almost always at least 15 dB weaker than the high horizontal.

Even though I have a pulley and rope over the tower to pull the 
Europe dipole back up, it isn't worth the hour's work to do that.
 
Into Alabama (about 150 miles):

The high horizontal and the vertical are a toss-up, the low 
horizontal is just a tiny bit weaker most nights. During the daytime 
the low horizontals are dogs, but the high horizontal works OK. AT 
that time the vertical is much better than any other antenna.

Into Atlanta (about 60 miles):

The low horizontal kicks butt at night. It is 20-30 dB louder than 
either the vertical or the high dipole. I have no daytime data for that 
distance.

If I worked DX under good conditions, especially right at the 
sunrise/sunset peak, and if I never had a good vertical I'd probably 
never miss it. But since I have all these antennas, and since I 
spent a year or more comparing them (and they are at least 500 
feet apart, so they don't interact much) I can provide data based on 
direct comparisons between some pretty good antennas at an in-
land location.

The opinion I've reached is I could certainly work DX with a low 
horizontal antenna on 160 meters, but the lower the wave angle the 
better. In the 70's I had an Inverted Vee dipole at 350 feet on 
WXEZ's tower in Ohio, and a 1/4 wl tower with 60 radials used to 
beat the high Inverted Vee dipole. Both antennas were in a swamp 
area. 

The same thing is true today in Georgia, with greatly different soil 
that should favor a horizontal.

Like Bill Fisher (W4AN) told me after a 160 contest, "the high 
horizontals aren't worth the money to run the tower lights". Keep in 
mind we could work Asia, Europe, and everywhere else on the 
dipoles...we were just 3-20 dB weaker at most places PLUS we 
had to switch dipoles to work stuff off the ends.


73, Tom W8JI
w8ji@contesting.com

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