89
15
OPTION UNIT INSTALLATIONS AND SETTINGS
■ AT-180 internal switch description
The optional AT-180 has 3 operating conditions for HF
band operation. Select a suitable condition according
to your antenna system.
q Remove the top cover of the AT-180.
w Set the tuner switches to the desired positions ac-
cording to the table below.
• Specifications for the AT-180
• Frequency coverage : 1.9–54 MHz
• Input impedance : 50 Ω
•Maximum input : 120 W
power
•Minimum tuning : 8 W
power
•Matching impedance : 16.7–150 Ω (HF band)
range 20–125 Ω (50 MHz band)
• Tuning accuracy : Less than SWR 1.5:1
• Insertion loss : Less than 1.0 dB
(after tuning)
•Power supply : 13.8 V DC/1 A (supplied from
requirements the transceiver’s ACC socket)
• Dimensions (mm/in) : 167(W)×58.6(H)×225(D)
6
9
⁄16(W) × 2
5
⁄17(H) ×8
7
⁄8(D)
• Weight : 2.4 kg; 5 lb 4 oz
• Supplied accessories : coaxial cable (1 m),
ACC cable (DIN 13 pins)
• AT-180 inside top cover
• Connector information for ACC(2) socket
PIN NO./
NAME
DESCRIPTION
q 8 V
Regulated 8 V output.
(10 mA max.)
w GND
Connects to ground.
e SEND
Input/output pin.
Goes to ground when transmitting (20 mA
max). When grounded, transmits.
r BAND
Band voltage output.
(Varies with amateur band; 0 to 8.0 V).
t ALC
ALC output voltage (–4 to 0 V).
y NC
No connection.
u 13.8V
13.8 V output when power is ON (1 A max).
SW Position
Operation
S1
A
(default)
The tuner operating condition is set by S2
described below.
B
THROUGH INHIBIT
The tuner tunes the antenna even when the
antenna has poor SWR (up to VSWR 3:1
after tuning). In this case, manual tuning is
necessary each time you change the fre-
quency although the tuner automatically
starts tuning when the VSWR is higher than
3:1. This setting is called “through inhibit,”
however, the tuner is set to “through” if the
VSWR is higher than 3:1 after tuning.
S2
C
TUNER SENSITIVE CONDITION
The tuner tunes each time you transmit (ex-
cept SSB mode). Therefore, the lowest
SWR is obtained at any given time.
For SSB mode, the same condition as the
“D” position.
D
(default)
NORMAL CONDITION
The tuner tunes when the SWR is higher
than 1.5:1. Therefore, the tuner activates
only when tuning is necessary.