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MFJ-1779B 80-40 Meter Dipole Antenna
INTRODUCTION
The MFJ-1779B one-half wavelength, single-band, dipole is a center-fed
antenna that can be tuned for operation on any frequency between 80 meters and
40 meters. (3.5-7.3 MHz) The antenna will handle full legal limit power. The
dipole is made using #14 copper wire, a durable center insulator enclosing an
SO-239 connector, and terminated with ceramic insulators. The ends of the
dipole are adjustable and should be cut to the desired length of operation. A
suitable length of wire comes with each antenna to achieve resonance at the low
end of each band.
WARNING: Never place the antenna in a location where contact
with power lines is possible. Death, serious injury, and
damage can occur.
CHOOSING A LOCATION
Choose a location clear from obstructions such as other antennas, buildings, and
power lines.
Never place the antenna near power lines.
Try to keep the
antenna away from metal buildings and other such structures, which will affect
the performance of the antenna. The optimum height of the antenna is 1/2
wavelength of the operating frequency above ground. This can be calculated by
dividing 468/ (frequency in MHz). Optimum antenna height will vary due to
different ground conditions and nearby objects.
The MFJ-1779B can be suspended from many different supports. The most
common being two trees. The antenna should be suspended using a weather
resistant, non-metallic, nylon rope. Always leave a few extra inches in the
support rope to allow for wind movement of the antenna. This is especially
important when trees are used for supports. If the rope is to tight the antenna
could be damaged.
The antenna can be installed in three different ways:
HORIZONTAL ANTENNA
This installation requires two supports with a minimum distance of the overall
length of the antenna. It is a good idea to also provide a support for the center
insulator of the antenna, which will relieve the stress on the center insulator.