SCS PTC-IIex, Manual

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5 PTC-Firmware
example, that on leaving the terminal program, (e.g. automatic de initialising with
Y
0 in
GP ) the PTC-IIex can be brought to a condition where a connect using the normal
MYCALL (i.e. without the -8) will be transferred to the mailbox. This is useful, as many
potential users would use the normal MYCALL to connect to the PTC-IIex.
If the terminal is off-line , and the configuration is correct, (
USers
0 or
Y
0) then all calls,
irrespective they are the normal MYCALL , the MYALIAS , or the BBS-MYCALL , will be
transferred to the PTC-mailbox.
5.7.6 Properties of mailbox-commands
Send
Text input can either finished with <Ctrl-Z> or with
***end
, as well known from other
mailbox systems. The
NNNN
sequence has no effect in PR !
Files that have been input via PR are signified in the status display (ST), the
LIst
- and
CHeck
- outputs by being marked with an X (AX.25), e.g: .... NX DL2FAK ...
The CONNECT LED starts to blink when a file is written via PR whose filename is the
same as the MYCALL of the PTC-IIex for channel 0.
Read
Even during a file read operation, it is possible to give further commands to the PTC
mailbox. These commands are stored in a buffer, and only acted upon when the relevant
file read operation is complete. An empty input (only <Return>), interrupts the file read
operation.
User
Lists the presently active links, similar to the
CStatus
command in the
pac:-
menu. A
presently active PACTOR link is displayed in channel 0 of the list and in addition marked
with the comment
PACTOR
. Every active link with the PTC mailbox is displayed with the
callsign of the connected station, together with the appropriate digipeater list.
PR links that are not connected to the PR-Box are displayed as a so called NON-BBS-
CONNECT , without however, the callsign of the opposite station.
5.8 The NAVTEX-Processor
5.8.1 NAVTEX General
The NAVTEX service, introduced a number of years ago as part of the GMDSS (Global
Marine and Distress Safety System), is a maritime news service, broadcasting weather,
navigational and safety information to shipping. This gives the impression that the system
uses the most modern technology. In fact, underneath the impressive sounding name, is
nothing other than a network of marine coast stations that
broadcast plain language messages using the SITOR-B system, at specific times. This
system is known to amateurs as AMTOR mode B or FEC. It uses the usual 170 Hz FSK
modulation system, which is also an old and wide spread system in HF digital radio. For
NAVTEX, only one MF channel on the frequency of 512 kHz has been allocated. The
transmission range is approximately 800 km. A range limitation is an essential part of the
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