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ANTENNA TUNER OPERATION
The internal automatic antenna tuner matches the
transceiver to the connected antenna automatically.
Once the tuner matches an antenna, the latching relays
combination are memorized as a preset point for each
frequency range (100 kHz steps). Therefore, when you
change the frequency range, the latching relays are au-
tomatically preset to the memorized combination.
CAUTION:
NEVER
transmit with the tuner ON
when no antenna is connected. This will damage
the transceiver. Be careful of the antenna selection.
Push [TUNER] to turn the internal antenna tuner
ON. The antenna is tuned automatically when the
antenna SWR is higher than 1.5:1.
• When the tuner is ON, the ‘TUNER’ indicator lights red.
• MANUAL TUNING
Push [TUNER] for 1 sec., to start manual tuning.
• A side tone is emitted and ‘TUNER’ indicator blinks
while tuning.
• If the tuner cannot reduce the SWR to less than 1.5:1
after 20 sec. of tuning, the ‘TUNER’ indicator goes out.
• PTT TUNER START
The tuner is always tuned when the PTT is pushed
after the frequency is changed (more than 1% from
last-tuned frequency). This function removes the
“push and hold [TUNER]” operation and activates for
the first transmission on a new frequency.
This function can be turned ON in initial set mode
(p. 81).
• TUNER RESET
q
Make sure the transceiver power is OFF.
w
While pushing [
Y
] and [
Z
], push [POWER] to turn
power ON.
• “
CLEAR ? OK
” appears as shown below.
e
Rotate main dial to select tuner reset.
r
Then Push [F-3] for 1 sec to start tuner resetting.
• The memorized tuner settings are reset.
[TUNER]
TUNER
Lights to indicate internal tuner is activated.
CLEAR ? OK
F 3
[POWER]
[
Y
]
[
Z
]
D
D
If the tuner cannot tune the antenna
Check the following and try again:
• the antenna connection and feedline.
• the unaltered antenna SWR.
(Less than 3:1 for HF bands;
Less than 2.5:1 for 50 MHz band)
• the power source voltage/capacity.
If the tuner cannot reduce the SWR to less than
1.5:1 after checking the above, perform the follow-
ing:
• repeat manual tuning several times.
• tune with a 50
Ω
dummy load and re-tune the antenna.
• turn power OFF and ON.
• adjust the antenna cable length.
(This is effective for higher frequencies in some cases.)
• Some antennas, especially for low bands, have a nar-
row bandwidth. These antennas may not be tuned at
the edge of their bandwidth, therefore, tune such an
antenna as follows:
NOTES:
• The internal antenna tuner can tune the HF to 50 MHz
bands.
•
NEVER
transmit without an antenna properly connected
to antenna port in use.
• If the SWR is higher than about 1.5:1 when tuning
above 100 kHz on an antenna’s preset point, push
[TUNER] for 1 sec. to start manual tuning.
• When strong impact is applied, the internal tuner may
not work properly caused by the latching relay is off po-
sition.
In this case, push [POWER] momentarily
to reset
the all latching relays while transceiver power is ON.
D
Internal antenna tuner
D
Tuner operation
■
Antenna tuner operation
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