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16
2
INSTALLATION AND CONNECTIONS
■
External antenna tuners and linear amplifier
Ground
Ground
Long wire or optional AH-2b
AH-4
ANT
IC-703
Coaxial cable
(from the AH-4)
CONNECTING THE AH-4
IC-703
Ground
Ground
AT-180
CONNECTING THE AT-180
HF
to 6 m
antenna
[TRANSCEIVER]
[ANT]
[ANT]
[ACC]
[ACC]
ACC cable supplied with the AT-180
Coaxial cable supplied
with the AT-180
one of two
connectors
Note:
Turn the IC-703’s power OFF when connecting
the AT-180, otherwise, the CPU may malfunction
and the AT-180 may not function properly.
CONNECTING A NON-ICOM LINEAR AMPLIFIER
R
WARNING:
•
Set the transceiver output power and linear ampli-
fier ALC output level referring to the linear amplifier
instruction manual. Be sure the linear amplifier key-
ing circuit control voltage is compatible with the IC-
703, before connecting to HSEND line (ACC cable).
•
The ALC input level must be in the range 0 V to
–4 V, and the transceiver does not accept positive
voltage. Non-matched ALC and RF power settings
could cause a fire or damage the linear amplifier.
•
The specifications for the SEND relay are 16 V
DC 0.5 A. If this level is exceeded, a large external
relay must be used.
HSEND
(Orange)
ALC (Blue)
13.8V (Gray)
Ground
Relay
RF IN
RF OUT
ALC
SEND
ANT
ACC cable
ACC
IC-703
50
Ω
coaxial cable
To an
antenna
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