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10-5
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Antenna tuner operation
The internal automatic antenna tuner matches the
transceiver to the connected antenna automatically.
After the tuner matches an antenna, the variable ca-
pacitor angles are memorized as a preset point for
each frequency range (100 kHz steps). Therefore,
when you change the frequency range, the variable ca-
pacitors are automatically preset to the memorized
point.
CAUTION: NEVER
transmit with the tuner ON when
no antenna is connected. This will damage the
transceiver. Be careful of the antenna selection.
D
D
Tuner operation
➥
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, [TUNER] switch indicator lights
green.
• While tuning, [TUNER] switch indicator blinks green.
• MANUAL TUNING
During SSB operation at low voice levels, the internal
tuner may not be tuned correctly. In such cases, man-
ual tuning is helpful.
➥
Push [TUNER] for 1 sec., to start manual tuning.
• A side tone is emitted and [TUNER] switch indicator
blinks red while tuning.
• If the tuner cannot reduce the SWR to less than 1.5:1
after 20 sec. of tuning, the [TUNER] switch indicator
goes out.
• AUTOMATIC TUNER START (HF bands only)
If you want to deactivate the tuner under conditions of
VSWR 1.5:1 or less, use the auto tuner start function
and turn the tuner OFF. This function activates the
tuner automatically when the SWR exceeds 1.5:1.
This function is turned ON in set mode. (p. 12-15).
NOTES:
•
NEVER
transmit without an antenna properly con-
nected to antenna port in use.
• When 2 or more antennas are connected, select
the antenna to be used with [ANT].
• 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.
• The internal tuner may not be able to tune in AM
mode. In such cases, push [TUNER] for 1 sec. to
manually tune.
[TUNER]
10
ANTENNA TUNER OPERATION