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Antenna Consideration
The FT-2900R is designed for use with antennas presenting an impedance of near 50
Ohms at all operating frequencies. The antenna (or a 50 Ohm dummy load) should be
connected whenever the transceiver is turned on, to avoid damage that could otherwise
result if transmission occurs accidentally without an antenna.
Ensure that your antenna is designed to handle 75 Watts of transmitter power. Some
magnetic-mount mobile antennas, designed for use with hand-held transceivers, may
not be capable of withstanding this power level. Consult the antenna manufacturer's
specification sheet for details.
Most all FM work is performed using vertical polarization. When installing a
directional antenna such as a Yagi or Cubical Quad, be certain to orient it so as to
produce vertical polarization, unless you are engaged in a special operating situation
where horizontal polarization is used. In the case of a Yagi antenna, orient the
elements vertically for vertical polarization; for a Cubical Quad, the feedpoint should
be at the center of one of the vertical sides of the driven element (or at a side corner, in
the case of a diamond-shaped Cubical Quad).
Excellent reference texts and computer software are available for the design and
optimization of VHF antennas. Your dealer should be able to assist you with all aspects
of your antenna installation requirements.
Use high-quality 50 Ohm coaxial cable for the lead-in to your FT-2900R transceiver. All
efforts at providing an efficient antenna system will be wasted if poor quality, lossy
coaxial cable is used. Losses in coaxial lines increase as the frequency increases, so an
8-meter-long (25' coaxial line with 1/2 dB of loss at 29 MHz may have a loss of 1.8 dB or
more at 146 MHz; choose your coaxial cable carefully based on the installation location
(mobile vs. base) and the overall length of the cable required (for very short runs of
cable in a mobile installation, the smaller, more flexible cable types may be acceptable).
For reference, the chart at the right shows approximate loss figures for
typically-available coaxial cables frequently used in VHF installations.
In outdoor installations, be certain to weatherproof all connectors thoroughly, as water
entering a coaxial cable will cause losses to escalate rapidly, thus diminishing your
communications effectiveness. The use of the shortest possible length of the highest
quality coaxial cable that fits within your budget will ensure the best performance from
your FT-2900R.
Mobile Installation
The FT-2900R must only be installed in vehicles having a 13.8 Volt negative ground
5
FCC ID:K6620393X50
IC: 511B-20393X50
Operating Manual
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