Kenwood TS-850S - Manual (Page 35)

4-8-1. RTTY
RTTY operation requires a demodulator and a
teletypewriter. A demodulator including 2125 and
2295 Hz (170 Hz shift) filters, will be acceptable and
may be connected directly to the REMOTE
connector. To use the transceiver’s FSK circuit with
older high voltage teletype equipment, you must use
an external keying relay in the teletypewriter closed
loop, and connect the relay contacts to the rear
panel RTTY terminal.
During FSK operation, the MARK frequency is
shown on the display.
RTTY SYSTEM
This transceiver will adapt to Slow Scan Television
or AFSK (Audio Frequency Shift Keying) RTTY
operation.
For SSTV, the ACC 2 connector should be
connected to the Camera output. The ACC 2
connector should be connected to the monitor input.
For AFSK operation, connect the Tone Unit output to
the ACC 2 input, and ACC 2 output to the Tone Unit
input.
RTTY jack TS-850S
AFSK keying signal.
RTTY devic<
AFSK receive signal
SS (Standby)
Speaker terminal
The figure below shows the frequency relationship
between receive and transmit with this transceiver.
In FSK operation the mark frequency is indicated on
the display.
Normally a mark frequency is transmitted when
the key is closed, and the space frequency is
transmitted when the key is open. Since a
shorting pin is inserted into the RTTY terminal at
the factory, the mark frequency is transmitted.
The polarity can be reversed so that the mark
frequency is transmitted when the key is open
with a power on function. (Please refer to Section
4-10-15.)
4-8-2. DATA COMMUNICATIONS
(PACKET, AMTOR, RTTY, SSTV,
etc.)
1. The ACC 2 connector has been provided for
connection of Data communications devices. All
necessary connections can be accomplished from
the same connector.
2. When using AFSK (Audio Frequency Shift Keying)
or modulating the signal with any form of audio
tones you should select LSB or USB. If F2
operation is desired select the FM mode. In
general LSB is used for RTTY and PACKET
communications in the HF band (FI), and USB is
used for AMTOR.
3. The transceiver will transmit according to the
signals received on the STBY connector. These
inputs are generated by the terminal unit in
response to inputs from the associated terminal
input device.
4. When using LSB, or USB the MIC gain control
should be used to adjust the input level for an on
scale ALC meter reading.
5. Pin number 9 of the ACC 2 connector is used to
disable the front panel microphone connector
during the periods that your communication
terminal is in use (grounding the pin accomplishes
this task). This prevents unwanted errors from in
your text.
Note
The display frequency 14.200.00 MHz.
The BFO normally uses the LSB mode for RTTY
operation. When the REV key is pressed, the
BFO changes to the USB mode. In the FSK-R
(FSK reverse) state, the display frequency is the
space frequency. If the other transceiver is using
reverse shift, the receiver polarity can be adjusted
with the REV key.
The display indicates the mark frequency even if
the shift width is changed.
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