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8
1
PANEL DESCRIPTION
D
DATA socket
D
ACC socket
ACC
PIN No. NAME
DESCRIPTION
SPECIFICATIONS
1
2
3
4
8
7
6
5
9
10
11
12
13
Rear panel view
q
brown
i
gray
w
red
o
white
e
orange
!0
black
r
yellow
!1
pink
t
green
!2
light
blue
y
blue
u
purple
!3
light
green
1
8 V
Regulated 8 V output.
Output voltage
: 8 V ±0.3 V
Output current
: Less than 10 mA
2
GND
Connects to ground.
———
Input/output pin.
(HF/50 MHz only)
Ground level
: –0.5 V to 0.8 V
3
HSEND Goes to ground when transmitting.
Output current
: Less than 20 mA
When grounded, transmits.
Input current (Tx)
: Less than 200 mA
4
BDT
Data line for the optional AT-180.
———
5
BAND
Band voltage output.
Output voltage
: 0 to 8.0 V
(Varies with amateur band)
6
ALC
ALC voltage input.
Control voltage
: –4 V to 0 V
Input impedance
: More than 10 k
Ω
7
NC
———
———
8
13.8 V 13.8 V output when power is ON.
Output current
: Max. 1 A
9
TKEY Key line for the optional AT-180.
———
“High” level
: More than 2.4 V
10
FSKK Controls RTTY keying
“Low” level
: Less than 0.6 V
Output current
: Less than 2 mA
11
MOD
Modulator input.
Input impedance
: 10 k
Ω
Connects to a modulator.
Input level
: Approx. 100 mV rms
AF detector output.
Output impedance : 4.7 k
Ω
12
AF
Fixed, regardless of [AF] position in
Output level
: 100–300 mV rms
default settings.
13
SQLS
Squelch output.
SQL open
: Less than 0.3 V/5 mA
Goes to ground when squelch opens.
SQL closed
: More than 6.0 V/100 µA
DATA
PIN No.
NAME
DESCRIPTION
1
2
3
4
5
6
Rear panel view
1
DATA IN
Input terminal for data transmit. (1200 bps: AFSK/9600 bps: G3RUH, GMSK)
2
GND
Common ground for DATA IN, DATA OUT and AF OUT.
3
PTT P
PTT terminal for packet operation. Connect ground to transmit data.
4
DATA OUT Data out terminal for 9600 bps operation only.
5
AF OUT
Data out terminal for 1200 bps operation only.
Squelch out terminal. Becomes ground level when the transceiver receives a signal
which opens the squelch.
6
SQ
• To avoid unnecessary TNC transmission, connect squelch to the TNC to inhibit trans-
mission when receiving signals.
• Keep audio output at a normal level, otherwise a “SQ” signal will not be output.
Color refers to the cable strands of the supplied cable.
ACC 1
ACC 2
q
FSKK
t
AF
w
GND
y
SQLS
e
HSEND
u
13.8 V
r
MOD
i
ALC
q
8 V
t
ALC
w
GND
y
VSEND
e
HSEND
u
13.8 V
r
BAND
1
2
3
4
8
8
7
6
5
9
10
11
12
13
1
2
3
4
7
6
5
1
2
3
4
7
6
5
Connect to ACC socket
• When connecting the ACC conversion cable (OPC-599)
1