Page 101
FT-950 O
PERATING
M
ANUAL
Most RTTY operation today is accomplished using a TNC or other computer-based system that utilizes AFSK tones. As
such, the previous discussion on LSB-mode “Packet” operation will apply for Baudot operation, as well. For RTTY opera-
tion using a Terminal Unit (TU) or the “FSK” output from a TNC, please see the discussion below. See also the illustration
for details regarding connection to your TU.
S
ETTING
U
P
FOR
RTTY O
PERATION
Before commencing RTTY operation, please direct your atten-
tion to the setup steps shown in the chart to the right.
B
ASIC
S
ETUP
RTTY
(
R
ADIO
T
ELETYPE
)
O
PERATION
1. To engage RTTY operation using “LSB” injection,
which is generally used in the Amateur service. Press
the [
RTTY/PKT
] button repeatedly until both the
“
” and “
” icons appear on the display.
2. To switch to USB-side injection in RTTY, press and
hold in the [
RTTY/PKT
] button. Both the “
” and
“
” icons will appear on the display.
3. When you begin typing on your TU or computer key-
board, the command to transmit should automatically
be sent to the transceiver, causing it to enter the trans-
mit mode.
N
OTE
:
If you anticipate making data transmissions of longer than
a few minutes, we recommend that you reduce the trans-
mitter power to 1/3 ~ 1/2 of its normal maximum via the
Menu item “
111 TGEN TX PWR
111 TGEN TX PWR
111 TGEN TX PWR
111 TGEN TX PWR
111 TGEN TX PWR
”.
A
DVICE
:
If you need to adjust the output level from the “DATA
OUT” pin (pin 5) of the
RTTY/PKT
jack on the rear
panel of the transceiver, please use Menu item “
061
061
061
061
061
RTTY OUT LVL
RTTY OUT LVL
RTTY OUT LVL
RTTY OUT LVL
RTTY OUT LVL
”. For the input level from the TU, there
is no adjustment of the FSK input level (Pin 4) of the
RTTY/PKT
jack. Please make any needed level ad-
justments at the TU side.
TO
1
ANT
DC IN
2
FROM
GND
ROT
LINEAR
TUNER
PTT
REC
REM
KEY
DMU
CAT
EXT
SPKR
INPUT: DC 13.8 V
22 A
-TUNE
-TUNE
AF
IN
PTT
FSK
OUT
F
S
K
IN
D
A
TA
O
U
T
D
A
TA
P
T
T
G
N
D
TU
N.C.
GND
PTT
FSK OUT
AF IN
N.C.
RTTY/PKT JACK
DATA IN (Pin 1)
Pin 6
GND (Pin 2)
DATA PTT (Pin 3)
FSK IN (Pin 4)
DATA OUT (Pin 5)
SQL OUT(
)
M
ENU
I
TEM
A
VAILABLE
V
ALUES
059 RTTY R PLRTY
nor (normal) / rEU (reverse)
060 RTTY T PLRTY
nor (normal) / rEU (reverse)
061 RTTY OUT LEL
0 ~ 100
062 RTTY SHIFT
170/200/425/850 (Hz)
063 RTTY TONE
1275/2125 (Hz)
The Mark/Space Shift utilized in most Amateur RTTY
operation is 170 Hz. Other shifts may be configured,
however, using Menu item “
062 RTTY SHIFT
062 RTTY SHIFT
062 RTTY SHIFT
062 RTTY SHIFT
062 RTTY SHIFT
”. The
FT-950
is set up for “high tone” operation (centered
on 2125 Hz) by default, but you may configure it for
low tone (1275 Hz) operation using Menu item “
063
063
063
063
063
RTTY TONE
RTTY TONE
RTTY TONE
RTTY TONE
RTTY TONE
”.
You may find that you are unable to decode some RTTY
stations, even if they are of sufficient signal strength.
If this is observed, there may be a Mark/Space polarity
problem between your station and the other station. If
so, try setting Menu item “
059 RTTY R PLRTY
059 RTTY R PLRTY
059 RTTY R PLRTY
059 RTTY R PLRTY
059 RTTY R PLRTY
” to
“
rEU
rEU
rEU
rEU
rEU
” (“Reverse”) to see if that permits copy. A sepa-
rate Menu Item permits reversal of your transmitter’s
Mark/Space polarity: “
060 RTTY T PLRTY
060 RTTY T PLRTY
060 RTTY T PLRTY
060 RTTY T PLRTY
060 RTTY T PLRTY
”.
Q
UICK
P
OINT
:
In the
FT-950
, “RTTY” is a mode defined as being an
“FSK” mode, whereby the closing and opening of a key-
ing line (to ground) causes the Mark/Space tones to alter-
nate. The RTTY mode is not an AFSK based mode in this
transceiver, and the AFSK output tones from a TNC will
not cause Mark/Space shifting to occur. Use the “Packet”
mode for AFSK-based Baudot and other data modes.