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3-8
3
INSTALLATION AND CONNECTIONS
■
FSK and AFSK (SSTV) connections
The transceiver has a Modem function for RTTY and
PSK. However, if you want to use a PC to operate
these digital modes, it is necessary to prepare the fol-
lowing interface circuit, or use a similar 3rd party de-
vice.
Refer to the instruction manual for the device prior to
connecting it.
PC
PC
[USB B] port
To USB port
USB cable (Purchase separately)
(2) When using the ACC socket or the microphone connector
(1) When using the USB port
8
2
7
6
1
3
5
4
C
E
B
No connection
No connection
Shield cable
2 k
˘
㸸
2 k
˘
10 k
˘
2 k
˘
:
2 k
˘
ACC1
10 k
˘
4.7 k
˘
4.7 k
˘
RTS
GND
10 k
˘
(Trimpot)
10 k
˘
(Trimpot)
Connection to
COM port of PC
D-Sub25
D-Sub9
Pin 4
Pin 7
Pin 7
Pin 5
Pin 2
Pin 3
Shield cable
Shield cable
Shield cable
Shield cable
C
E
B
TXD
The sections shown in squares are required
only when Baudot RTTY is used in FSK (RTTY) mode.
(Other digital mode operations such as SSTV or PSK are not required.)
*1 NPN transistor
(2SC1815)
(Rear panel view)
(Front panel view)
¡
When connecting to [ACC1]
¡
When connecting to [MIC]
*2 switching diode
(1S1588)
*1
*1
*2
*2
A
A
B
B
C
C
D
D
E
E
1
2
3
4
5
6
7
8
B
F
E
D
C
*3 Connect to [C] when using ACC1.
Connect to [F] when using the microphone connector.
Example interface circuit for digital modes
(Not provided by Icom)
*3
Connection to
LINE IN or MIC
IN of PC
Connection to
SP OUT of PC
NOTE:
You cannot operate RTTY
(FSK) operation when you
connect the circuit to the
microphone connector.
Set a USB condition on the "USB keying (RTTY)" set-
ting when operating RTTY.
(p. 15-19)