Topbanders:
The following is unscientific! It based on looking at notes from my 160M
logs over the years and from memory (caution: my previous call was W2CRS).
My first 160M operation was in 1957 from near Washington DC. I used a
quarter wave wire averaging about 30 feet above ground which was snaked
around the back yard. It was plugged directly into the back of my Viking 2.
At age 16, was I the youngest to regularly check into the Greybeard Net?
And what happened to that venerable net? I was able to work stations up and
down the coast and sometimes as far west as W0-land. I listened to W1BB and
others work DX, but I couldn't hear it.
Then-
After college, in the late 1960's and early 70's, I used Drake twins on 160M
from Schenectady County, NY, with a sloping dipole up 50 feet in the center
and maybe 30' on the ends. I listened to W1BB, K1PBW, and others work DX,
and I sometimes could hear "garden variety DX" and occasionally work it.
At a different location, 15 miles away, in the late 70's and early 80's I had
a another sloping dipole with the center at 60' and the ends at about 30.
With both these dipoles and low power I could only occasionally work Europe
and other DX. I notice in my logs that in a couple of 160M contests I did
not even work California!
Then-
Moving to central Colorado in 1988, I put up another sloping dipole with the
center and ends up around 40'. This was on the top of a hill and I was able
to work the east coast frequently with low power. I also worked JA, VK, and
other south Pacific DX, but not Europe which I assumed was almost impossible
with my setup. I did a lot of broadcast band DXing and heard many TP
(transPacific openings), but no TA's (even using a 1000' NE beverage) which
had been somewhat common back in NY. I think I might have worked Europe
knowing what I know now. I did fairly well with the low dipole during a
couple of 160M contests, almost doubling my best score from NY.
Then-
in 1991, I acquired a Hygain Hytower 52' vertical. I put several thousand
feet of radials on the ground and used a loading coil to resonate the Hytower
on 160M. I found that the Hytower vertical almost always outperformed
the low dipole beyond three hundred miles or so. I took down the dipole. I
did not try to work much DX with the Hytower, but I operated several contests
in 1991, '92, and '93 coming in as high as 5th place, single op, North
America, low power division in ARRL contest 1991. I did even better 1992 and
'93 contests, but there were more and better stations active in 1992 and 1993
so I didn't place as high.
Then-
with a Titan amp acquired around 1993, I tried to figure out a way to run
high power on 160M. I put the low dipole up again but I was often as loud on
the Hytower vertical with 100 watts as on the dipole with a KW. Even after
modifying the insulators on the Hygain Hytower (it's only good for maybe 200
watts, unmodified, on 160M), I burned them up, more than once.
Then-
In 1994 I put up a sloper. The top was was connected to the top of my 40'
tower wallbracked to the house. The sloper was about 90' feet long (with a
coil at about 60' to reonate it on 160M) and ran down the hill to the east at
about a 40 degree angle. The far end was about 10' above ground and about
50' below the top of the tower. I found that by putting several radials at
the base of the 40' tower, the antenna worked better indicating, as some of
the literature suggests, that the tower (which had a 432 EME array on it) was
being loaded! The tower was literally only 5' from my operating position and
I felt uncomfrotable using it with high power. Also, at more than a KW, it
caused feedback in the transceiver which was only 4 feet from the tower.
Nevertheless, the sloper performed pretty well, as well or almost as well as
he Hytower vertical on most of my A/B tests. And I could run a KW to it. I
also worked some Europeans with it, the first time I worked Europe since
moving to Colorado. In the 1994 ARRL 160M contest, friend KF7MD and I
operated multiop finishing about 20th multiop in the country with a decent
score.
Then-
In September of 1995 put up a full wave loop in the draw (valley for you
easterners!) below and east of my house. It averaged about 40' above ground
and was actually about 20' below my operaing level at the house. The land
fell off towards the east and north. Surprise, this low full wave loop
turned out to be a better receiving AND transmitting antenna to the east
coast and to Europe than the sloper. Of course, the FW loop was blocked by
the hill to the west and didn't work well at all in that direction. In
October I took down the sloper and put up a second full wave loop. This was
a sloping full wave loop. In fact, one corner was at the 40' level on my
wall bracked tower where the sloper had been conected. With the west leg of
the sloper about 40' above ground on top of the hill and the east leg 10'
above ground and 50' below the west leg, my north and south legs were sloping
east at about a 35 degree angle. In A/B tests, this sloping FW loop
performed better to the east and to Europe on both transmit and receive than
did the Hytower vertical often by a S-unit, sometimes more. It wasn't as
good as the Hytower vertical in other other directions.
On at several occasions, this FW loop was at least the equal of several
Colorado 1/4 wave verticals to Europe, but under most conditions it was not
as good as those same verticals. On one occasion that fall, K0CS who has a
good 1/4 wave vertical and KV0Q with a good 4-square and I compared signals
with stations on the east coast. I was about 2 s-units down from KV0Q and 1
s-unit down from K0CS, both locals. In the 1995 ARRL 160M contest using the
FW loop and the remodified Hytower at a KW, friend Paul, KF7MD, and I
improved our score and ranked 2nd multiop in the Midwest Division and about
15th nationwide.
Then-
during the summer of 1995 I acquired about 6 sections of Rohn 25. I dug a 4'
hole and used one 10' section in concrete as the start of a dedicated 160M
vertical. Every couple of months I added a 10' section. I'm on the top of a
hill so anything I put up is high profile for neighbors within a mile or so.
The tower grew slowly and, with the acquistion of more Rohn sections, grew
to 80' by August of this year. I did not operate 160M last year season. I
was watching my tower grow! By late August this year, I had put 10' of mast
above the tower and about 45' of wire to resonate it at 1900 KHz. I also put
down first ten, then ten more and now a total of thirty 150' and longer
radials.
In A/B/C tests, the new 160M vertical, shunt fed and configured as an
inverted L, averages about an S-unit better than the Hytower or sloping full
wave loop. My amp was not working in September and also the variable cap at
the tower was not large enough for high power, but I managed to worked quite
a few VKs (and a YB), ZS, and European stations while running only 100-200
watts. Now running a KW, I am no longer a little pistol, but am no where
near being a big gun like K0HA, AA0RS, and KV0Q. I listen to those guys work
stuff that is barely perceptable here!
Summary and back to the topic-
The low horizontal dipoles at my location on top of a hill were never as good
as even a Hytower vertical except for very short skip. The low sloping FW
loop did a credible job (70 countries worked with it during the 1995 season)
and may turn out to be my best antenna on rare occasions.
The new 160m vertical described above has outperformed my FW loop and Hytower
vertical on all ocasions so far. I think that on my hill with mostly clay
soil and some granite, a vertical, even an inefficient one, outperforms a low
dipole. Whether a high dipole or inverted V might be better than my new
vertical, I don't know. At some time in the future I'll string an inverted V
from 90' atop my new vertical and find out.
In the meantime, I plan to lay down another 30 radials and change the
vertical from an inverted L to a tophat configuration, maybe coaxing another
dB out of the system.
I also need to work on my 700' NE beverage which never has worked very well.
Most of the time I hear better on my transmitting antenna than on the
beverage.
Well, if you got this far, thanks for listening to my little jog down memory
lane!
And now, 40 years later, that I'm old enough for the Graybeard net, there
isn't one! Time sure does fly!
Doug W0AH Woodland Park CO
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