![background image](http://html.mh-extra.com/html/icom/ic-7410/ic-7410_instruction-manual_612268053.webp)
46
4
RECEIVE AND TRANSMIT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
D
About the RTTY reverse mode
Received characters are occasionally garbled when
the Mark and Space signals are reversed. This rever-
sal can be caused by incorrect TNC connections, set-
ting or commands.
To receive reversed RTTY signals correctly, select the
RTTY reverse mode.
➥
Push [RTTY] to alternately select the RTTY mode
or RTTY reverse mode.
D
RTTY decoder
The transceiver has an RTTY decoder for Baudot
(mark freq.: 2125 Hz, shift freq.: 170 Hz, 45 bps).
An external terminal unit (TU) or terminal node con-
nector (TNC) is not necessary for receiving a Baudot
signal.
q
In the RTTY mode, push [MENU] to display the “M1”
screen (Menu 1).
w
Push [RTTY](F-4) to display the “RTTY” screen.
e
Push [F-2](DEC) to turn ON the RTTY decoder.
• RTTY decoder screen appears.
r
Push [F-2] to turn ON the Hold function to hold the
current screen.
• “
H
” appears when this function is turned ON.
• Push [F-2] again to turn OFF the Hold function.
t
Hold down [F-3] for 1 second to clear the displayed
characters
, if desired.
• “
H
” disappears at the same time as the displayed char-
acters are cleared. (The hold function is cancelled.)
y
Push [MENU] to return to the previous display.
• Setting the decoder threshold level
If some characters are displayed when no signal is re-
ceived, adjust the RTTY decoder threshold level.
q
Select the RTTY decoder screen as described
above.
w
Push [F-1](ADJ) to select the threshold level adjust-
ment mode.
e
Rotate [DIAL] to adjust the RTTY decoder threshold
level.
• Hold down [F-3] for 1 second to reset to the default set
-
ting, if desired.
r
Push [MENU] to save, and return to the previous
display.
The number of the decoder display lines, the Un-
Shift On Space (USOS) function and new line code
can be set in the RTTY Set mode. (p. 48)
Normal
Reverse
170 Hz
170 Hz
2125 Hz
2125 Hz
BFO
BFO
Space
Space
Mark
Mark
AGC
1 / 4
RTTY
S C P
M1
D E C
T P F
S E T
RTTY
DEC
45BPS
BAUDOT
MK ⁄ SFT
2125 ⁄ 170
F2 : HOLD
F3 : CLR
A D J
H
Appears when the Hold function
is turned ON.
DEC
45BPS
BAUDOT
MK ⁄ SFT
2125 ⁄ 170
F2 : HOLD
F3 : CLR
≈
9
DEC
45BPS
BAUDOT
MK ⁄ SFT
2125 ⁄ 170
F2 : HOLD
F3 : CLR
A D J
Threshold level display