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4-35
4
RECEIVE AND TRANSMIT
■
Data mode (AFSK) operation
When operating
RTTY, SSTV,
AMTOR or PACKET
with your TNC and/or PC software in the AFSK mode,
consult the manual that comes with the TNC and/or
the software.
q
Connect a PC and TNC to the transceiver. (p. 2-9)
w
Push a band key to select the desired band.
e
Push
SSB
or
AM/FM
to select the desired op-
erating mode.
r
Push
DATA
to turn data mode ON.
• One of “-D1,” “-D2” or “-D3” is additionally appears.
• During data mode selection, hold down
DATA
for 1
second to select data mode 1 (D1), 2 (D2) and 3 (D3)
in sequence.
t
Rotate the main dial to tune to the desired signal
and decode it correctly.
• Also use the tuning indicator of the TNC or software.
• During SSB data mode, the
1
⁄
4
tuning function can be
used for critical tuning.
y
Operate the PC (software) or TNC to transmit.
• When operating in SSB data mode, adjust the TNC
output level so that the ALC meter reading doesn’t go
outside the ALC zone.
NOTE:
When data mode 1 (D1) is selected, the
audio input from the [ACC1 (pin 4)] is used for
transmission instead of [MIC]’s.
(Modulation input con-
nector can be changed in ACC set mode (pp. 12-7, 12-8).
DATA1: [ACC], DATA2: [MIC] and [ACC], DATA3: [MIC] are
defaut settings. )
The fixed condition is used for SSB data transmis
-
sion as follows:
• [COMP]
: OFF
• Tx bandwidth
: MID
• Tx Tone (Bass) : 0
• Tx Tone (Treble) : 0
✔
For your information
Carrier frequency is displayed when SSB data mode
is selected.
See the diagram to the left for the tone-pair example.
170 Hz
2125 Hz
2295 Hz
Mark
Space Carrier frequency
(displayed frequency)
Appears
Main dial
Band keys
[AF]
AM/FM
DATA
SSB
• Mark and Space tones of RTTY in the AFSK
mode operating in the LSB mode