Operation Manual

M-2 AIS Operation Issue 1 51
"beacon" or "msg 17" respectively to indicate the source of the differential data
being used.
External SOG/COG in use (Information 27)
Internal SOG/COG in use (Information 28)
These messages indicate whether Speed over Ground and Course over Ground
are being supplied by the external sensors or are being calculated from the
internal GNSS module.
Heading valid (Information 31)
This message is received when a valid heading is first received from the ship's
sensors.
Rate of Turn indicator in use (Information 33)
Other ROT source in use (Information 34)
The first of these messages indicates that the M-2 transponder is using Rate of
Turn information from an on-board device which directly calculates the rate of
turn - such as a gyro compass. The second message indicates that the rate of
turn is being calculated from changes in the ship's heading.
Chan management params changed (Information 36)
This message is issued each time that any of the channel management
parameters are altered. These may be altered by the receipt of specific VHF or
DSC messages from base stations and can also be modified directly by using
the "Channel Regions" page on the M-2's display unit.
All transmissions enabled (Information 63)
All transmissions disabled (Information 64)
These two messages indicate that all transmissions by the transponder have
been enabled or disabled as appropriate. When the transponder is first powered
up it is not allowed to transmit for a period while it listens to transmissions from
nearby vessels in order to ensure that it does not interfere with them. The
message "All transmissions disabled" is displayed as a reminder that the AIS is
not operational for this time. After approximately 90 seconds, the transponder
will begin transmissions and the message “All transmissions enabled" is
displayed.
These messages are also generated if the transmitter is inhibited while the AIS
unit is in operation.
Own reports enabled (Information 65)
Own reports disabled (information 66)
These messages are displayed when the transmission of AIS "Own Vessel"
reports are enabled or disabled as a result of moving across the boundary of
channel management region. When moving into a channel management region