Icom IC-78 Instruction Manual - Page 28

RTTY FSK operation, RTTY AFSK operation

Page 28 highlights

4 OPERATION ï RTTY (FSK) operation q Connect a terminal unit as at p. 25. 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 selec- tor. t Operate the connected PC or TNC (TO). PRESETTING FOR RTTY • Tone frequency q Push [SET] for 1 sec. to enter quick set mode. w Push [∫ UP]/[√ DN] several times until "TON 2125" appears, then rotate the channel selector to select the desired tone frequency. • Shift frequency q Push [SET] for 1 sec. to enter quick set mode. w Push [∫ UP]/[√ DN] several times until "SIFT 170" appears, then rotate the channel selector 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, etc. To receive a reversed RTTY signal correctly, select RTTY-R (RTTY reverse) mode. • Push [MODE] for 1 sec. to select RTTY-R (RTTY reverse) mode. Normal space mark 170 2125 Hz Hz BFO displayed freq. ï RTTY (AFSK) operation q Connect a terminal unit as on p. 25. 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). 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. 26

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4
OPERATION
26
ï
RTTY (FSK) operation
q
Connect a terminal unit as at p. 25.
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 selec-
tor.
t
Operate the connected PC or TNC (TO).
PRESETTING FOR RTTY
•Tone frequency
q
Push [SET] for 1 sec. to enter
quick set mode
.
w
Push [
UP]/[
DN] several times until “TON 2125”
appears, then rotate the channel selector to select
the desired tone frequency.
• Shift frequency
q
Push [SET] for 1 sec. to enter
quick set mode
.
w
Push [
UP]/[
DN] several times until “SIFT 170”
appears, then rotate the channel selector 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, etc.
To receive a reversed RTTY signal correctly, select
RTTY-R (RTTY reverse) mode.
• Push [MODE] for 1 sec. to select
RTTY-R (RTTY re-
verse) mode.
ï
RTTY (AFSK) operation
q
Connect a terminal unit as on p. 25.
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).
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.
RTTY mode
is selected.
Reverse
Normal
BFO
170
Hz
2125
Hz
170
Hz
2125
Hz
BFO
mark
space
displayed freq.
displayed freq.
mark
space