Using The Automatic Antenna Tuner; Atu Operation - Yaesu FTDX9000D - DATA MANAGEMENT Operation Manual

U A
SING THE UTOMATIC
The Automatic Antenna Tuner (hereinafter referred to as the "ATU") built into each FT
50-Ohm load for the final amplifier stage of the transmitter. We recommend that the ATU be used whenever you operate on
the FT 9000D.
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The ATU of the FT
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transceiver at the station end of your coaxial cable feedline. It does not "tune" the SWR at the antenna feedpoint
itself. When designing and building your antenna system, we recommend that every effort be made to ensure a
low SWR at the antenna feedpoint.
The ATU of the FT
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one per Amateur band, so that each band has at least one setting preset for use on that band. The remaining 89
memories are reserved for the 89 most-recent tuning points, for quick frequency change without the need to
retune the ATU.
The ATU in the FT
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corresponding to an SWR of 3:1 or less. Accordingly, simple non-resonant whip antennas, along with random-
length wires and the "G5RV" antenna (on most bands) may not be within the impedance matching range of the ATU.
[ TUNE ] switch
1. Rotate the [ RF PWR ] control fully clockwise (to the
right).
2. Use the [ Main Tuning Dial ] knob to set the radio to
desired operating frequency within the Amateur band.
3. Press the [ TUNE ] switch momentarily to place the
ATU in the transmit line (no adjustment/tuning will
occur yet). An LED inside the [ TUNE ] switch will
glow red continuously.
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The momentary press of the [ TUNE ] switch will turn
the tuner on, and the microprocessor will automati-
cally select the tuning point closest to the current op-
erating frequency.
4. Press and hold in the [ TUNE ] switch for two seconds
to begin automatic tuning. The transmitter will be en-
gaged, and the red LED imbedded in the [ TUNE ]
switch will blink while tuning is in progress. When
the optimum tuning point has been reached, the radio
will return to receive, and the red LED will again glow
steadily (instead of blinking).
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A T
NTENNA UNER
A A A A A
9000D, being located inside the station, only adjusts the impedance presented to the
9000D includes 100 memories for tuning data. Eleven of these memories are allocated,
9000D is designed to match impedances within the range of 16.5 Ohms to 150 Ohms,
ATU O
[ RF PWR ] knob [ Main Tuning Dial ] knob
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PERATION
"HI-SWR" (LED glows Red)
5. While tuning around the band using the Main tuning
dial, you will observe that the [ TUNE ] LED blinks
momentarily every 10 kHz. This momentary blink-
ing indicates that a new tuning window has been en-
tered. If you want to save tuning data associated with
this 10 kHz window, repeat step 4 (above) for each
such window. On bands like 1.8 MHz where the im-
pedance may change rapidly, the storage of a number
of tuning points is recommended.
6. To disconnect the ATU from the transmit line, press
the [ TUNE ] switch momentarily. The red LED im-
bedded in the [ TUNE ] switch will go out, confirming
that the ATU has been turned off. In the "Off" mode,
the transceiver will be directly connected to the co-
axial cable connected to your antenna, and will oper-
ate based on whatever impedance is present at the
station end of the coax.
The ATU is connected both to the transmitter and
the receiver, and its natural RF selectivity has a
beneficial effect in rejecting out-of-band energy
during reception. Accordingly, we recommend that
the ATU be left "On" at all times.
FT
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9000D is crafted to ensure a
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9000D O M
PERATION ANUAL