DIGITAL SELECTIVE CALLING
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12
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General
When an optional UX-120
DSC UNIT
is installed, digital selec-
tive calling (or DSC) can be used via the IC-M59. DSC is a
method of radio communications involving digital signals
rather than the more conventional method of voice commu-
nications. The advantage of using digital communications
over voice communications is that information (especially
useful for distress calls and other urgent matters) can be pre-
programmed into a radio and transmitted accurately.
UX-120 required
In addition, when a GPS receiver (NMEA0183 ver. 1.5, 2.0 or
2.1) is connected, your vessel’s position and the current UTC
time are transmitted together with the vessel’s identity when
making a distress call.
See p. 27 for unit installation.
DSC TYPE
DESCRIPTION
REF.
Distress call
This sends distress information which includes your vessel’s ID (and position data/UTC time
when a GPS receiver is connected). Send under
emergency conditions only.
DSC acknowl-
edgement will be received from a coast station after making a distress call.
pgs.
13, 16
Distress relay call
This is used to alert Coast stations (or other ships) when a vessel in distress is unable to do
so. The IC-M59 can
only receive
this type of signal; not transmit.
p. 16
All ships call
This is used for non-emergency situations. This signal includes information which allows a re-
ceiving transceiver to automatically select a specified channel for voice communication.
pgs.
14, 16
Individual call
This allows you to send a signal to a specific vessel only. The vessel’s ID code must be pre-
programmed in advance. Two kinds of acknowledgements (able to comply/unable to comply)
are available (for sending or receiving) after an individual call.
pgs.
15, 17
Geographical area call
This is used for announcement to all ships in the specified area—when a GPS receiver is
connected calls directed to areas other than yours are rejected.
Receive only
for the IC-M59.
p. 17
