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11 SPECIALIZED COMMUNICATIONS
RADIO TELETYPEWRITING (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
typed 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 the cable connections, see “RTTY” {page 95}.
For further information, consult reference books
about Amateur Radio.
1 Access Menu No. 38 and select an FSK shift.
• FSK shift is the difference in frequencies
between a mark and a space.
• The 170 Hz default is used on the Amateur
bands.
2 Access Menu No. 39 and select a key-down
polarity.
• Select “NORMAL” to transmit a mark when
keying down or “INVERS” to transmit a space.
The default is “NORMAL”.
3 Access Menu No. 40 and select high tone
(2125 Hz) or low tone (1275 Hz) for mark.
• High tone (default) is commonly used
nowadays.
4 Select an operating frequency.
5 Press [CW/ FSK/ REV] to select FSK.
• “FSK” appears.
6 If necessary to be compatible with the other
station, press [FUNC], [CW/ FSK/ REV] to reverse
the transceiver to the upper sideband.
• “FSR” appears.
• Traditionally, the lower sideband is used for
FSK operation.
• Press [FUNC], [CW/ FSK/ REV] to return to
the lower sideband.
7 Following the instructions provided with your MCP,
enter a command from your computer to select
transmit mode.
• The MAIN band LED changes from green (RX)
to red (TX).
• You may instead press [SEND] to manually
select the transmit mode.
8 Begin sending data from your computer.
• Use Menu No. 50C to select the appropriate AF
output level. The AF control cannot be used
for this adjustment.
• Press [FUNC], [PWR/ TX MONI] to monitor
your signals. Press [FUNC], [PWR/ TX MONI]
again to quit this function.
9 When finished transmitting, enter a command from
your computer to return to receive mode.
• The MAIN band LED changes from red (TX) to
green (RX).
• If you pressed [SEND] in step 7, press [SEND]
again.
The frequencies (measured in kHz) commonly used
for RTTY operation are listed below:
adanaC/.A.S.U
1noigeRURA
)acirfA/eporuE(
0481~00812481~8381
)0953:XD(5463~50630263~0853
)0407:XD(0017~08075407~5307
05101~0410105101~04101
5.99041~070415.99041~08041
01181~0018190181~10181
00112~0701202112~08012
03942~0294292942~02922
05182~0708205182~05082
Note: You may adjust the carrier level when necessary. Press
[FUNC], [MIC/ CAR] to enter the adjustment mode. With a key down
condition, turn the MULTI/ CH control so that the ALC meter reads in
the ALC zone but does not exceed the upper ALC zone limit.