SCS PTC-IIex, Manual

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6 Commands
cmd:
NAV
ALL <Return>
The two arguments “ Maximum number of entries in the NAVTEX directory” and “ List of
letters for choosing the message types” can be entered together. The order of input is of
no importance. E.g.:
cmd:
NAV
ABDE 50 <Return>
cmd:
NAV
70 CDEF <Return>
cmd:
NAV
ALL <Return>
6.65.3 Choice of the message area codes
If one wishes to receive messages from a few special coast stations, these can be set by
using the command
NAV AREA
. This can often be a useful choice, as a skipper in the
Mediteranean Sea will have (presumably) no interest in navigational messages concerning
the North Sea or Baltic. The area codes allocated to the individual coast stations can be
easily found out by inspecting the message contents.
If one wishes to receive messages from coast stations M, N and Z, then the PTC is
informed of this with the command
NAV AREA
<Enter>.
cmd:
NAV AREA
MNZ <Return>
The order of the letters is unimportant. Again however, there should be no spaces
between the letters.
The special argument "ALL" is also allowed here. The command
cmd:
NAV AREA
ALL <Return>
allows the reception of messages from all areas. The command
cmd:
NAV AREA
<Return>
without an argument displays the present area codes chosen.
6.65.4 Choosing the message latency time
A somewhat advanced setting possibility allows the PTC-IIex to decide after what time
period the message is no longer valid. This command is the argument "
DAYS
" which may
follow the
NAVtex
command. It can contain a number between 0 and 365. This sets the
time the message will be counted as valid. If a message is received containing the same
four figure message identifier as a previously stored message, then the message is classed
as a repetition when it is received within the latency period. If received outside the
latency period, then the NAVTEX processor interprets the new message as a
different
one, and stores it without checking for errors as an independant message. The setting
cmd:
NAV DAYS
0 <Return>
turns off the NAVTEX processors automatic update, all messages are written
consecutively in the NAVTEX directory, even when message identifier duplication is
present. The default setting
cmd:
NAV DAYS
3 <Return>
is a practical value for continuous operation and needs not to be changed. The command
cmd:
NAV DAYS
<Return>
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