Icom IC-78 Instruction Manual page 28

3
OPERATION
RTTY (FSK) operation
D
q Connect a terminal unit as on
w Select RTTY (or RTTY-R) mode with [MODE].
e Select the desired FSK tone and shift frequencies
as below.
r Set the desired frequency with the Channel Se-
lector.
t Operate the connected PC or TNC (TO).
PRESETTING FOR RTTY
• Tone frequency
q Hold down [SET] for 1 second to enter the Quick
Set mode.
w Push [UP p] or [q DN] several times until "TON
2125" is displayed, then rotate the Channel Selec-
tor to select the desired tone frequency.
• Shift frequency
q Hold down [SET] for 1 second to enter the Quick
Set mode.
w Push [UP p] or [q DN] several times until "SIFT
170" is displayed, then rotate the Channel Selec-
tor to select the desired tone frequency.
• RTTY reverse mode
Received characters are occasionally garbled when
the receive signal is reversed between MARK and
SPACE. This reversal can be caused by incorrect
TNC connections, settings, commands, and so on.
To receive a reversed RTTY signal correctly, select
RTTY-R (RTTY reverse) mode.
RTTY (AFSK) operation
D
q Connect a terminal unit as on
w Select SSB (LSB) mode with [MODE].
• Generally, LSB is used on the HF bands.
e Select the desired FSK tone/shift frequencies and
keying polarity the same way as FSK operation.
r Set the desired frequency with the main dial.
t Operate the connected PC or TNC (TO).
25
page 24.
page 24.
• Hold down [MODE] for 1 second to select RTTY-R
(RTTY reverse) mode.
Normal
space mark
170 2125
Hz
Hz
BFO
displayed freq.
RTTY mode
is selected.
RTTY mark frequency
is set to 2125 Hz.
2125, 1615 and 1275
Hz are available.
RTTY shift frequency
is set to 850 Hz.
850, 425, 200 and
170 Hz are available.
Reverse
space mark
2125 170
Hz
Hz
BFO
displayed freq.