ICOM IC-7000 说明手册

10

114

The AT-180 automatic antenna tuner matches the IC-
7000 to the connected antenna automatically. Once the
tuner matches an antenna, the variable capacitor setting
are memorized as a preset point for each frequency
range (100 kHz steps). Therefore, when you change the
frequency range, the variable capacitors are automati-
cally preset to the memorized point.

• The AT-180 can match both HF and 50 MHz

bands. However, operation is different for the HF
and 50 MHz bands.

• When connecting the AT-180, the IC-7000’s output

power must be set over the 10 W. Otherwise, the
AT-180 may not be tuned correctly. (AT-180’s min-
imum operating input power is 8 W.)

[TUNER/CALL]

The AT-180 cannot be used for the 144/430 MHz
bands. When operating on the 144/430 MHz band,
pushing 

selects the call channel

(p. 100).

transmit with the tuner ON

when no antenna is connected. This will damage
both the transceiver and antenna tuner.

■

D

Push 

to turn the tuner ON. The an-

tenna is tuned automatically during transmission
when the antenna SWR is higher than 1.5:1.

• When the tuner is ON, “

” indication appears.

Push and hold 

for 1 sec. to tune the

antenna. If “

” indicator blinks slowly while trans-

mitting, push and hold 

for 1 sec.

again to re-tune the antenna.

D

During SSB operation on HF bands at low voice lev-
els, the AT-180 may not be tuned correctly. In such
cases, manual tuning is helpful.

Push 

for 2 sec. to start manual tun-

ing.

• CW mode is selected, a side tone is emitted, and “

”

indicator blinks; then, the previous mode is selected.

If the tuner cannot reduce the SWR to less than 1.5:1
after 20 sec. of tuning, “

” indicator disappears.

In this case, check the following:
• the antenna connection and feedline
• the antenna SWR (p. 36; meter function)

(HF bands only)

The AT-180 has a through inhibit condition. When se-
lecting this condition, the tuner can be used at poor
SWR’s. In this case, automatic tuning in the HF bands
activates only when exceeding SWR 3:1. Therefore,
manual tuning is necessary each time you change the
frequency. Although termed “through inhibit,” the tuner
will be set to the “through”  configuration if the SWR is
higher than 3:1 after tuning.

(HF bands only)

If you require critical tuning at any time during trans-
mission, select the tuner sensitive condition. See
p. 131 for selection.

(HF bands only)

If you want to turn OFF the tuner under conditions of
VSWR 1.5:1 or less, use “automatic tuner on” and
turn the tuner OFF. See p. 130 for turning the function
ON and OFF.