Antenna Tuner Operation; D Tuner Operation - Icom IC-7800 Instruction Manual

■ Antenna tuner operation

D Tuner operation

[TUNER]
• MANUAL TUNING
• AUTOMATIC TUNER START (HF bands only)

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
capacitors 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.
➥ 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.
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 tun-
ing above 100 kHz on an antenna's preset point,
hold down [TUNER] for 1 second to start manual
tuning.
• The internal tuner may not be able to tune in AM
mode. In such cases, hold down [TUNER] for 1
second to manually tune.
During SSB operation at low voice levels, the internal
tuner may not be tuned correctly. In such cases, man-
ual tuning is helpful.
➥ Hold down [TUNER] for 1 second, 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 seconds of tuning, the [TUNER] switch indicator
goes out.
If you want to deactivate the tuner under conditions
of VSWR 1.5:1 or less, use the auto tuner start func-
tion 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. 12-16).
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