Furuno FS-1570 - Manual (Page 40)

3 DSC OVERVIEW
3-4
3.2.2 Individual call
The individual call is for sending a call to a specific station.
Coast
Station
Own Ship
(1) DSC Message [Called Acknowledge
Request (ACK RQ) Signal]
(2) Acknowledge Back (ACK BQ) Signal
(3) Voice or telex communication
(1)
(2)
(3)
Basic procedure (radiotelephone)
1. Prepare call and transmit it by pressing the [CALL] key. The equipment then awaits
acknowledgement of the call.
2. Receive acknowledge back (ACK BQ) signal from other party (coast station or ship
station) within about five minutes. The audio alarm sounds at this time; press the
[CANCEL] key to silence it.
3. After receiving the ACK BQ signal, communicate with other party; the radiotelephone
automatically sets the working frequency and class of emission you specified.
3.3 Audio Alarms
When you receive a distress alert or routine call addressed to your ship, the audio and
visual alarms are released. For the distress or urgency call, the audio alarm sounds until
the [CANCEL] key is pressed, and sounds for one second and then automatically goes off
in case of other calls. The tone of the alarm changes with the call received. By becoming
accustomed to the tone, you can know which type of call you have received.
Alarm Frequency (interval)
Safety call received 1300 Hz and 0 Hz (250 ms)
Routine, Ship's Business call
received 880 Hz and 440 Hz (500 ms)
While DISTRESS button is
pressed for three seconds 2200 Hz and 0 Hz (125 ms)
Distress alert is being sent 2200 Hz, continuous
Own ship position not updated 2200 Hz (50 ms), three beeps
every two seconds