Operation Manual

Page 36 FT-897 OPERATING MANUAL
DIGITAL MODE OPERATION
(
SSB-BASED AFSK
)
The FT-897 provides extensive capability for digital mode
operation on the HF, VHF, and UHF bands. The use of AFSK
(Audio Frequency-Shifted Keying) configurations allows a
wide variety of different communication modes to be uti-
lized. The Menu provides for specific digital mode selec-
tions, which include custom BFO offsets to optimize the
receive and transmit passbands for the mode selected.
Before beginning Digital operation, you need to define which
Digital mode will be utilized. To do this, use Menu #38 as
follows (in this example, we will set up RTTY as the Digital
mode):
1. Press and hold in the
[
F
]
key for one second to enter the
Menu mode.
2. Rotate the MEM/VFO CH knob to select Menu Mode
No-038
[
DIG MODE
]
.
3. Rotate the DIAL knob to select “RTTY-L” or “RTTY-U”
(see discussion below).
4. Press and hold in the
[
F
]
key for one second to save the
new setting and exit.
Use this technique to set up any digital mode.
RTTY
(
Radio TeleType
)
Operation
The “RTTY” mode on the FT-897 is available in either LSB-
side or USB-side BFO injection. Long-standing Amateur
practice calls for the use of LSB-side injection, but some
applications require that you use USB-side injection.
1. Connect your TNC (Terminal Node Controller) or ter-
minal modem to the FT-897’s rear-panel DATA jack,
per the illustration. Be sure to use the “TX AUDIO” line,
not an “FSK” line, for the transmit data connection to
the FT-897.
TRANSMITTER OPERATION
3. If the optional YF-122C 500 Hz filter has been installed,
it may be used for RTTY work. Recall Multi Function
Row “n”
[
CFIL, -----, -----
]
, then press the
[
B
](
-----
)
or
[
C
](
-
----
)
key to engage the narrow filter.
4. To set up the transmit side, be sure that the Meter is set
to monitor ALC voltage. If not, press the
[
F
]
key mo-
mentarily, then rotate the MEM/VFO CH knob to select
to select Multi Function Row “i”
[
MTR, -----, DISP
]
, then
press the
[
A
](
MTR
)
or
[
B
]
key so as to select metering
of ALC (“ALC” icon will appear at the upper of the
[
B
]
key).
5. Press and hold in the
[
F
]
key for one second to enter the
Menu mode, then rotate the MEM/VFO CH knob to se-
lect Menu Mode No-037
[
DIG GAIN
]
.
6. Following the instructions for your TNC’s software, ac-
tivate the transmitter from the computer keyboard; this
should cause the AFSK output from the TNC to be sent
to the radio. While transmitting, view the ALC meter; a
few “dots” of ALC indication should be observed. If not,
rotate the DIAL knob to adjust the AFSK level within
the FT-897 for seven to eight dots of indication on the
ALC meter.
7. Press and hold in the
[
F
]
key for one second to save the
new AFSK level setting and return to normal operation.
You are now ready for full RTTY operation.
Because RTTY is a continuous-duty transmis-
sion mode, try to keep your transmission short
when running on battery power, so as to mini-
mize current drain.
PTT
DATA IN
GND
AFSK
OUT
AF IN PTT
DATA OUT
2. Press the MODE
(

)
or MODE
(

)
key, as needed, to
select the DIG mode (the “DIG” icon will appear on the
display). You should now be able to tune around the band,
and any RTTY signals heard should be capable of being
decoded.