[K0WA wrote:]
> What is the collective experience with a lower dipole?
[N0AX responds:]
>> Assuming we're talking 80-m here, I wouldn't bother with the low dipole
>> except for regional coverage where a high radiation angle is a Good
Thing.
>> Low, horizontal wires aren't going to put much energy below 30 degrees of
>> vertical angle.
While there is no disputing the fact that low dipoles and inverted vees on
80M have virtually no directional characteristics and are high-angle
radiators, I would hesitate to discourage anybody from putting one up if
circumstances preclude more effective antennas or placement. Full-length low
dipoles and vees *do* work. No, they won't beat a properly installed beam,
vertical, or sloper, but they can provide an excellent alternative to
nothing at all! Also, in my experience, they are much more effective than
the shortened multiband verticals on the market.
If your interest is DX, then the answer depends to some extent on your QTH.
In the heart of the midwest, a low dipole or vee is bound to be a
frustrating DX antenna. But it can be used to work some pretty good DX from
the East and West coasts. A low dipole or vee won't break any contest
records on 80M, but will perform adequately from anywhere in the U.S. for
North American contests like Sweepstakes, and will get you some DX
multipliers from the Western Hemisphere. If you're on the East or West
coast, you can get plenty of DX multipliers from Europe or the Pacific,
respectively.
I've worked 123 DXCC countries (104 confirmed) with five sub-optimal 80M
antennas. The first was an R5 multiband vertical, which didn't play at all
outside the U.S. The next was a Windom with one end at no more than 25 feet
up and the other end at about 40 feet (it sort of sloped up from the peak of
the roof to a tall tree.) I worked one country (UK) on the Windom in about 8
months. Then I replaced the Windom with a full-length dipole mounted at the
same end points. Even with that pathetic configuration, I worked 73
countries on that dipole in about five years. After moving, I used a GAP
Titan multiband vertical for a while. It was pretty much a dummy load on
80M, but I worked 9 countries with it in about two years. Finally, I put up
a full-size inverted vee with the apex at 65 feet. That's been my best 80M
antenna by far. I've worked about 40 countries with the vee in 18 months.
That pushed me over 100 confirmed on 80M for my 5BDXCC and got me to the
present 123.
The inverted vee is, of course, excellent for communications within New
England. It plays reasonably well within the entire continental U.S., and
I've not been terribly unhappy with it during North American contests like
Sweepstakes. From time to time, it works quite well into Europe and South
America. Every now and then it works into Africa and even Asia (I confirmed
Japan on 80M recently.) Most of the time, I have to listen real hard to hear
low-power DX stations above the static crashes and have to use a KW to
reliably work anything outside North America.
So, a low dipole or vee isn't a barn burner -- I'll probably be over 100 by
the time I work 'em all on 80M with mine. Certainly, there are better
antennas if you can get the height, or some horizontal space for elevated
radials or a sloper. But, you can still have a lot of fun with a low dipole
or vee if you have better antennas on other bands to use when conditions are
below average on 80M.
73, Dick, WC1M
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