37 data communications.indd.pdf, Data communications, Radio teletype (rtty) – Kenwood TS-590S User Manual

Page 45: Phase-shift keying 31 baud (psk31)

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37

DATA COMMUNICATIONS

RADIO TELETYPE (RTTY)

RTTY is the data communications mode with the
longest history. It was originally designed for use with
mechanical teletypewriters which were often used
before personal computers became common. Now
you can easily start operating RTTY with a personal
computer and MCP. Unlike Packet, each time you
type a letter, it is transmitted over the air. What you
type is transmitted and displayed on the computer
screen of the recipient.

RTTY operation uses frequency shift keying (FSK)
and the 5-bit Baudot code or the 7-bit ASCII code to
transmit information.

For cable connections, refer to “RTTY OPERATION”
{page 68}.

For further information, consult reference books about
Amateur Radio.

1 Access Menu No. 44 and select an FSK shift.

• FSK shift is the difference in frequencies

between a mark and a space.

• The 170 Hz shift (default) is normally used on

the Amateur bands for the RTTY.

2 Access Menu No. 45 and select a key-down

polarity.
• Select “oFF” (default) to transmit a mark when

keying down or “on” to transmit a space.

3 Access Menu No. 46 and select “2125” (high tone)

or “1275” (low tone) for mark.
• High tone (default) is commonly used

nowadays.

4 Select an operating frequency.

5 Press

[CW/FSK (REV)] to select FSK mode.

• “FSK”

appears.

• If necessary, access Menu No. 67 to configure

the appropriate audio output level for your
MCP. The audio output level of ANO (ACC2
connector/ pin 3) changes {page 65}. The AF
control cannot be used to adjust the audio level
for your MCP.

6 Some stations may be operating in Reverse shift.

In this case, press and hold [CW/FSK (REV)] to
reverse the shift (the upper sideband is used).
• “FSR”

appears.

• Traditionally, the lower sideband is used for

FSK operation. Press and hold [CW/FSK
(REV)]
again to return to the lower sideband.
“FSK” appears.

7 Follow the instructions provided with your MCP

and enter a command from your computer to
transmit.
• The TX-RX LED changes from green (RX) to

red (TX).

8 Begin sending data from your computer.

• Press and hold [PWR (TX MONI)] to monitor

your signals. Press and hold [PWR (TX MONI)]
again to quit this function.

9 When finished transmitting, enter a command from

your computer to return to reception mode.
• The TX-RX LED changes from red (TX) to

green (RX).

The following frequencies (measured in kHz) are
commonly used for RTTY operation:

U.S.A./ Canada

IARU Region 1

(Europe/ Africa)

1800 ~ 1840

1838 ~ 1842

3605 ~ 3645 (DX: 3590)

3580 ~ 3620

7080 ~ 7100 (DX: 7040)

7035 ~ 7045

10140 ~ 10150

10140 ~ 10150

14070 ~ 14099.5

14080 ~ 14099.5

18100 ~ 18110

18101 ~ 18109

21070 ~ 21100

21080 ~ 21120

24920 ~ 24930

22920 ~ 24929

28070 ~ 28150

28050 ~ 28150

PHASE-SHIFT KEYING 31 BAUD (PSK31)

PSK31 is a digital modulation method used in
amateur radio communications. You can perform data
communications in real-time using a keyboard, like
RTTY. Additionally, because of the narrow bandwidth
(31.25 Hz) you can even use PSK31 on congested
frequencies. Another merit to PSK31 is that it can
be enjoyed with a simple antenna and low transmit
power.

Using the sound function of your PC along with
PSK31 software, many amateur radio operators enjoy
PSK31.
• Refer to “TNC AND MCP” {page 69} for

connections.

• When managing PSK31 using the sound capability

of a PC, use SSB mode.

• Set AGC to fast.
• Turn off the speech processor.
• Refer to “EXTERNAL AUDIO SETTINGS”

{page 58} for Audio Settings.

For further information, consult reference books about
Amateur Radio.

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