20 METER INSTALLATION
INTERNATIONAL ANTENNA COMPANY
888-268-4214CLICK HERE FOR PRINTABLE PDF
You are the proud owner of the new DOUBLE BAZOOKA ANTENNA. The first thing to do is to consider
which direction you want your maximum signal to radiate. The Antenna tends to be omni-directional, however,
the largest lobes radiate from the sides. If you want your maximum signal to radiate North and South, extend the
ends East and West. The antenna should be mounted in an inverted "V" configuration for the best results. The
apex should be 25 to 40 feet above around. However, the antenna can be installed as a horizontal dipole with
equally good performance.
Mounting on a push up pole or tower is easiest. Suspend the apex of the antenna from the eyehook provided at
the center of the "T" mold. Next, extend the ends of the antenna outward and downward so the antenna forms an
upside down "V". Mount the ends at least 10 to 30 feet above the ground forming an angle of no less 120
degrees from horizontal. Were horizontal would be 180 degrees. The ends may be fastened with cord to poles or
whatever, using proper safety rules in safeguarding that persons, pets, and other objects cannot come in contact
with any of the elements as shock hazards or RF burns could result.
• Whenever connecting the ends of the antenna to an object it is recommended that a light or medium
relief “springs” with a safe working load limit of 5 lbs be installed to compensate for any movement of
the antenna or connecting object. “DO NOT USE A TENSIONER DEVICE”
• If mounting the antenna as a horizontal dipole without a center support it is recommended to use a
messenger line to reduce the strain on the antenna. A messenger (nylon cord line) should be installed
from one mounting end through the center eyehook to the other mounting end.
After mounting, the antenna connect a 50 ohm feed line such as RG-58, RG-8 or RG-213 coax to the antenna and your
transmitter. With a very low amount of output power applied to the antenna at your desired frequency, measure the SWR.
An antenna analyzer may also be used to measure the SWR. The antenna should exhibit an SWR of less than 2:1 across
the entire 20 meter band. The antenna is cut for the CW portion of each band from the factory so further adjustment is
To lower the SWR,fold the 300-ohm twin lead back on itself ensuring it is flat on itself with no gaps equally on
each side. The fold of 12, 24, 36 or 48 inches must be done in a (single fold over not multiple fold overs). This
procedure will raise the operating frequency of the CW portion of the band. For more detail see tuning
instructions on the IAC website located in the information section.
A foldover of approx. 24 inches on each side will provide a resonance on 7.200 MHz. Once the lowest SWR
is obtained tie wrap the folded end securely to retain its position. If you measure a higher SWR, make sure that
the antenna is not near or touching any metal objects such as rain gutters, aluminum siding, metal roofs, etc.
After making sure the SWR is within spec and everything is clear of the antenna. You are ready to operate and
enjoy all of the great signals and DX contacts that this antenna offers.
We at IAC wish you the greatest DX' ing and are sure you will be pleased with your purchase.
IAC ACCEPTS NO LIABILITY FOR DAMAGE OR INJURY RESULTING FROM THE
INSTALLATION AND USE OF THIS ANTENNA.