Thrane&Thrane TT-3020C, Руководство по настройке

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Transceiver Configuration
Configuring the VMS behaviour
Page 4-20 9-Nov-00
When the Inmarsat-C signal is blocked for approximately 11½
minutes (80 Inmarsat TDM frames) and the GPS signal is still pr e-
sent the transceiver will go into a mode where it stores positions in
non -volatile memory.
At the same time the transceiver will start to give an audio alarm to
indicate to the operator that it is time for manual scanning of NCS's
due to high bulletin board error level.
When Inmarsat signal becomes OK again and has been OK for
approximately 3½ minutes i.e. the level where the audio alarm
stops because the transceiver has synchronised to a satellite, the
stored positions are transmitted to the VMS DNID, LES pair. One
position report at a time spaced 3 minute s from the completion of
the previous stored position transmission. This ensures 3 minutes
of NCS TDM listening between every report which will allow EGC
reception like safety calls or weather forecasts.
The interval used for storage of positions in non -volatile memory is
the short interval specified in the fishery configuration (see section
4.1.23 Reporting intervals)
. The first position stored is spaced this
short interval from the time of signal lost e.g. if short interval is 2
hours the first position is stored 2 hours after the Inmarsat signal
is lost. The position and the time when the Inmarsat signal is lost
is transmitted in an Antenna Blocked position report.
The feature is configured by entering 51 in the fishery command
entry.
4.1.22 Position report packet 2 - bit mask
The idea of this entry is to allowed a Message Terminal or data
terminal (only TT-3022D) to set some bits in the position report
packets.
This entry in the Fishery Configuration is used to select the bits in
the position report packet number 2 that can subsequently be
changed by the Message Terminal/data terminal software.