Yaesu FT DX 9000 CONTEST - 2, Руководство по эксплуатации

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Page 12 FT
DX
9000 C
ONTEST
O
PERATION
M
ANUAL
I
NSTALLATION AND
I
NTERCONNECTIONS
A
NTENNA
C
ONSIDERATIONS
The FT
DX
9000 Contest is designed for use with any antenna system providing a 50 Ohm resistive impedance at the desired
operating frequency. While minor excursions from the 50-Ohm specification are of no consequence, the transceiver’s
Automatic Antenna Tuner may not be able to reduce the impedance mismatch to an acceptable value if the Standing Wave
Ratio (SWR) present at the Antenna jack is greater than 3:1.
Every effort should, therefore, be made to ensure that the impedance of the antenna system utilized with the FT
DX
9000
Contest be as close as possible to the specified 50-Ohm value.
Any antenna to be used with the FT
DX
9000 Contest must, ultimately, be fed with 50 Ohm coaxial cable. Therefore, when
using a “balanced” antenna such as a dipole, remember that a balun or other matching/balancing device must be used so as
to ensure proper antenna performance.
The same precautions apply to any additional (receive-only) antennas connected to the RX ANT jack; if your receive-only
antennas do not have an impedance near 50 Ohms at the operating frequency, you may need to install an external antenna
tuner to obtain optimum performance.
A
BOUT
C
OAXIAL
C
ABLE
Use high-quality 50-Ohm coaxial cable for the lead-in to your FT
DX
9000 Contest transceiver. All efforts at providing an
efficient antenna system will be wasted if poor quality, lossy coaxial cable is used. This transceiver utilizes standard “M”
(“PL-259”) type connectors, except for the “RX OUT” BNC connectors used for special filters, etc.
Typical PL-259 Installation
1/16"
3/4"
1 1/8"
3/4''
1/8''
5/8'' 3/8''
Adapter