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12
SETUP AND CONNECTIONS
12-7 Data communications
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
A
A
A
B
B
B
C
C
C
D
D
D
E
E
F
*
E
F
*
F
*
AFSK OUT
AF IN
PTT
GND
SQL IN
RS-232C
cable
AMTOR • PACKET
PC
*When connecting the squelch line, consult the necessary manual (TNC, etc.)
Rear
panel
view
Rear
panel
view
“HIGH” level
: More than 2.4 V
1
RTTY
Controls RTTY keying.
“LOW” level
: Less than 0.6 V
Output current
: Less than 2 mA
2
GND
Connects to ground.
Connected in parallel with ACC(2) pin 2.
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
Connected in parallel with ACC(2) pin 3.
4
MOD
Modular input
Input impedance
: 10 k
Ω
Connects to a modulator
Input level
: Approx. 100 mV rms
5
AF
AF detector output
Output impedance
: 4.7 k
Ω
Fixed regardless of [AF] position.
Output level
: 100 to 300mV rms
Squelch output.
Squelch open
: Less than 0.3 V/5 mA
6
SQLS
Goes to ground when squelch
Squelch closed
: More than 6.0 V/100 µA
opens
7
13.8 V
13.8 V output when power is ON.
Output current
: Max. 1 A
Connected in parallel with ACC(2) pin 7.
Control voltage
: –4 to 0 V
8
ALC
ALC voltage input.
Input impedance
: More than 10 k
Ω
Connected in parallel with ACC(2) pin 5.
PIN NO.
ACC(1)
NAME
DESCRIPTION
SPECIFICATIONS
2
8
4
5
1
3
6
7
Rear panel
view
Output voltage
: 8 V ±0.3 V
1
8 V
Regulated 8 V output.
Output current
: Less than 10 mA
2
GND
Same as ACC(1) pin 2.
3
HSEND
Same as ACC(1) pin 3.
4
BAND
Band voltage output.
Output voltage
: 0 to 8.0 V
(Varies with amateur band)
5
ALC
Same as ACC(1) pin 8.
Input/output pin (144 MHz only)
6
VSEND Goes to ground when transmitting.
Ground level
: –0.5 V to 0.8 V
When grounded, transmits.
Output current
: Less than 20 mA
7
13.8 V
Same as ACC(1) pin 7.
PIN NO.
ACC(2)
NAME
DESCRIPTION
SPECIFICATIONS
2
4
5
1
3
6
7
Rear panel
view
• When connecting to ACC(1)
• When connecting to [MIC]
The IC-746 can be connected to AMTOR/PACKET or
AFSK teletype units via the rear panel ACC sockets or
the front panel [MIC] connector. When using such units
be sure to consult the appropriate manuals.
Summary of Contents for IC-746
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