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Using CB Antennas on the 10 Meter Ham Band By N4UJW
When
the band is "open" it does not take loads of power,
multielement arrays or lots of skill to make contacts to
distant lands and fellow hams around the world.
In making "DX" contacts, (contacts out
of your country), you will want your signal to reach out as far as
possible at a low angle to the earth's horizon and not go out at a high
angle relative to the earth.
The lower the angle of radiation, the further
your signal will go bouncing further and further around the globe using
the ionosphere as your "reflector" in space.
Having an antenna that has a low angle of
radiation on 10 meters is of great importance in getting those
DX stations to hear a stronger signal from you. Using low angle radiation
type vertical antennas also greatly improves your chances over your
"local" area also. Many operators use 10 meter mobile rigs in their
vehicles with of course vertical antennas mounted on them, so in order for
you to communicate with them at any distance, your antenna must be the
same polarizaton...vertical.
So what types of antennas have a low angle of
radiation that will reach those local operators AND DX stations with
the same antenna you may ask?
Enter the vertically polarized
antenna.
There are many ways to utilize a
vertical antenna on the 10 meter band from simple homebrew wire
verticals hung in a tree to commercially built high dollar
multielement beam antennas designed for this purpose.
Use a CB antenna on 10
meters!
One of the simpler ways of getting a really
good low angle signal out at much less expense is to use a vertical CB
antenna converted to 10 meters. Yes, you read that correctly....a CB
antenna.
Many of the commercially made CB antennas can
be easily converted to 10 meter use by just a simple tuning modification
of the CB antenna length. Since they were originally designed for 11
meter use on the CB band, they are usually longer than those required for
the 10 meter ham band due to the difference in
frequencies.
So by using an old CB antenna OR a new one
that may be very inexpensive, you can modify it by shortening it until you
get the lowest swr on your favorite band, 10 meters.
There are several brands and models of
commercially made vertical CB antennas that have been designed to
cover many of the ham bands "outside" of their original design parameters
of the CB band.
So what would be a good commercial CB antenna to use on 10 meters? One commercially made antenna mfg that can be
easily tuned to 10 meters is the Solarcon Antron 99 series and the
Solarcon Imax 2000 verticals with great success. These particular
verticals come with a tuning adjustment that will enable them to be used
even down to 20 meters with a tuner. They get very highly rated reviews
and are very popular among 10 meter operators and have been used for many
years. They work well without a tuner when used on 10 meters due to their
wide frequency range design.
The adjustment to take them "up" to 10 meters
is a simple matter of a shortening of the vertical element and a fine
tuning of a "tuning" ring adjustment for lowest swr.
The Antron A-99 antenna is a 17 foot tall
antenna as designed and the Imax 2000 is 24 feet tall when it comes from
the factory.
Either of these antenna can be readily used
on 10 meters with just a bit of simple tuning and you will be very
pleased at their performance. They get great reviews and are widely
used.
The A-99 is the least expensive of the 2
models at around $60.00, 2011 prices, and the Imax 2000 is usually
under $100.00. Both are fiberglass and will handle more than the legal
limit of rf power.
So bottom line, if you don't want to build
your 10 meter antenna or convert that old CB antenna you may have laying
around, then these antennas are highly recommended and highly
rated for the 10 meter operator who wants to get more signal out to
the horizon for those DX contacts.
Reader feedback:
From John, KL7JR: 73, just my two cents worth! KL7JR Check them out
below!
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