Audio Alarms - Furuno FM-8900S Operator's Manual

2. DSC OVERVIEW
Contents of a DSC call
• Calling category
DISTRESS: DISTRESS ALERT, DISTRESS RELAY ALL, DISTRESS RELAY IN-
DIVIDUAL, DISTRESS RELAY AREA (Received only), DISTRESS ACK
GENERAL: MEDICAL MSG, NEUTRAL MSG, INDIVIDUAL MSG, PSTN MSG,
TEST MSG, GROUP MSG, ALL SHIPS MSG, POSITION MSG, POLLING MSG
• Station ID (MMSI)
Your ship ID and sending station ID. Coast station ID begins with 00; Group ID be-
gins with 0.
• Priority
Distress: Grave and imminent danger and request immediate assistance.
Urgency: A calling station has a very urgent call to transmit concerning safety of
ship, aircraft or other vehicle or safety of person.
Safety: A station is about to transmit a call containing an important navigational or
meteorological warning.
Routine: General calling
• Communication mode
TELEPHONE: Telephone (16K0G3E(F3E)) by VHF radiotelephone
• Communication channel
Working frequency channel used to call by telephone. The sending station may
have the receiving station (ship or coast station) assign the frequency channel to
use.
• Position
Position can be automatically or manually set.
• End code
The end of a DSC call is indicated with "RQ" (acknowledgment required), "BQ" (ac-
knowledgment) or "EOS" (no acknowledgment required).
2.3

Audio Alarms

When you receive a distress alert or general call addressed to your ship, the audio and
visual alarms are released. The audio alarm can be silenced with the CANCEL key.
Alarm
Count Counting down the time remaining before the distress
alarm alert is transmitted.
Distress The following sessions are received:
RX alarm distress alert, relay individual, relay area, or relay all.
Distress Sending or resending the distress alert.
TX alarm
Distress The following sessions are received or received then ac-
ACK knowledged:
alarm distress ACK, distress ACK (cancel ACK), relay individ-
ual ACK, or relay all ACK.
Urgency The following urgency sessions are received:
alarm all ships, neutral, medical, or individual.
Urgency The sessions for urgency individual ACK are received
ACK then acknowledged. The sessions for delayed ACK are
alarm received.
2-2
When Frequency (interval)
2000 Hz (500 ms)  silent
(500 ms); three times
2200 Hz (250 ms)  1300 Hz
(250 ms); repetition
2200 Hz (2000 ms); once
2200 Hz (500 ms)  1300 Hz
(500 ms); repetition
2200 Hz (250 ms)  silent
(250 ms); repetition
2200 Hz (500 ms)  silent
(500 ms); repetition