Sailor RT5022 VHF DSC, Operation Manual

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Detail
4.6.3 Automatic channel shift
The VHF can be set to automatically changing the working channel on receipt of the
following call types:
• Individual radiotelephony acknowledgement with a valid channel information
• Radiotelephony group calls with valid channel information
• Radiotelephony all ship safety calls with valid channel information
The set-up is done via menu 4.5.5. The setting will survive powering off the product.
If enabled, a received call will start the (normally) periodic alarm only once. The channel will
switch immediately after and the window is closed.
The automatic channel shift is overruled (turned to manual acknowledgement - requiring
press on OK or a hook-on to hook-off transition) if:
• Any handset is hooked off
• The received call cannot currently be presented on the information display (due to
priority)
Distress calls and all ship calls with category distress or urgency will alert continuously until
manually handled from the front panel.
4.7 Implicit behaviour for operations with DSC
This section describes assumptions and decisions made that are critical for correct function-
ality, but might be hidden to the operator in the display.
4.7.1 DSC transmission
All DSC calls are transmitted on channel 70 with a transmitter power of 25W. Distress,
urgency and non-test safety calls are always transmitted. Other calls are sent only if the
radio is not already recognizing a DSC message on channel 70.
4.7.2 Transmitting undesignated distress
Undesignated distress (solely created using the DISTRESS button) does not show any
message prior to the actual transmission. The following message will be sent:
Format specifier: Distress (112)
Self-Id: <Your MMSI number>
Nature of distress: Undesignated (107)
Distress coordinates: Automatically inserted if position is available (e.g. from GPS),
otherwise unknown (9999999999)
Time of position: Automatically inserted if time of position is available (e.g. from GPS),
otherwise unknown (8888)
Subsequent communication: 100
EOS: 127
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