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7
ANTENNA TUNER OPERATION
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7-1
About the internal antenna tuner
The internal automatic antenna tuner automatically
matches the transceiver to the antenna within the
range of 16.7 ~ 150 Ω (SWR of less than 3:1).
After the tuner matches an antenna, the latching relay
combinations are memorized as a preset point for
each frequency range (100 kHz steps). Therefore,
when you change the frequency range, the latching
relay combinations are automatically preset to the
memorized point for fast tuning.
•
When you install a new antenna, or you want to
change the antenna settings, you can clear the all
of the internal antenna tuner preset points with the
“<<Preset Memory Clear>>” item on the TUNER set
screen. (p. 8-3)
MENU
»
SET > Function > Tuner >
<<Preset Memory Clear>>
• You can select whether or not to save the internal
antenna tuner’s status after pushing
TUNER
on each
band in the “[TUNER] Switch” item on the TUNER
set screen.
(p. 8-3)
MENU
»
SET > Function > Tuner >
[TUNER] Switch
NOTE:
When the transceiver receives a strong physical
shock, the internal latching relays may be returned to an
unlatched condition. In that case, push
TUNER
to turn
OFF the tuner, then turn ON again to reset the all latching
relays.
Internal antenna tuner operation
1. Push
TUNER
to turn ON the internal antenna
tuner.
•“TUNE” is displayed when the tuner is ON.
2. Tune the antenna.
L
To tune the antenna, see “Manual tuning” or “PTT
Tuner start” below.
D
Manual tuning
You can manually tune the antenna before transmitting
for the first time.
1.
Hold down
TUNER
for 1 second to start manual
tuning.
•
The tuner reduces the SWR to less than 1.5:1 after
2~3 seconds of tuning.
L
While tuning, a side tone is heard and “TUNE” blinks
red.
2. After tuning, “TUNE” is displayed.
L
If the tuner cannot reduce the SWR to less than 1.5:1
after 20 seconds, tuning stops and “TUNE” goes out.
D
PTT Tuner start
The tuner is always activated when PTT is pushed
after the frequency is changed (more than 1% from
last-tuned frequency). This function tunes the antenna
for the first transmission on a new frequency.
L
This function can be turned ON in the “PTT Start”
item of the TUNER set screen.
(p. 8-3)
MENU
»
SET > Function > Tuner >
PTT Start
NOTE:
•
If the SWR is higher than about 1.5:1 when tuning more
than 100 kHz on an antenna’s preset point, hold down
[TUNER] for 1 second to start manual tuning.
•
If you transmit into a high SWR, “TUNE” may blink. In that
case, hold down
TUNER
for 1 second to manually tune.
If the tuner cannot tune the antenna
•
Repeat manual tuning several times.
•
Even if the tuner cannot tune the antenna on the first
tuning, it may success at the second tuning.
•
Some antennas, especially for the low bands, have a
narrow bandwidth. These antennas may not tune at
the edge of their bandwidth, therefore, tune such an
antenna as follows:
(Example):
Suppose you have an antenna which has an SWR of
1.5:1 at 3.55 MHz and an SWR of 3:1 at 3.8 MHz.
1.
Set 3.55 MHz, and hold down
TUNER
for 1
second to start manual tuning.
2.
Set 3.80 MHz, and hold down
TUNER
for 1
second to start manual tuning.