NAVTEX / AMTEX
49
Once a message has been received from a particular station with less than a specified amount of
errors, it will not been printed again, as the receiving system keeps track of the message numbers
it has received. If it then sees the same message class and number from the same transmitting
station, it will not output the message to the terminal.
For ARRL AMTEX bulletins, the defined B1 codes are:
A
ARRL issued bulletins
C
CRRL issued bulletins (Canadian)
I
IARU issued bulletins
J
JARL issued bulletins
S
AMSAT issued bulletins
X
Miscellaneous
and the currently assigned message classes are:
A
Emergency bulletins
B
Priority bulletins
D
Reserved
E
DX bulletins
G
General bulletins
K
Keplarian bulletins
P
Propagation forecasts
S
Satellite bulletins
X
Miscellaneous bulletins
NAVTEX / AMTEX Operation
To enter the NAVTEX/AMTEX mode, you simply type
NAVTEX
from the
cmd:
prompt and press re-
turn. At this point you will see nothing on the terminal until a valid NAVTEX message is received.
To exit the NAVTEX mode and return to the
cmd:
prompt, type a
Ctrl-C
followed by the letter
X
.
(Do not hold the control key when you type the X.)
Before entering the NAVTEX Mode (while you still have the
cmd:
prompt) you may specify which
stations you wish to receive using the NAVSTA command. For instance, if I wish to copy AMTEX
bulletins issued by ARRL, but do not want those from other stations (CRRL for example), I would
type
NAVSTA A
at the
cmd:
prompt. To monitor all stations, simply type
NAVSTA ALL
.
You may also specify which message classes you wish to receive by using the NAVMSG command.
If you want the Satellite bulletins and DX bulletins, you would type
NAVMSG ES
and press return.
Note, that if you eliminate message classes A, B, or D from the list of valid message classes, you
will receive a WARNING message from the
KAM
since the NAVTEX specification requires that these
classes must be printed at least once. To set your system to copy all message classes, type
NAVMSG ALL
.
The NAVERR command is used to specify the percent of errors allowed in a received message be-
fore
KAM
considers the message as not being received properly.
In the event you wish to clear the message sequence numbers, allowing all messages to be re-
ceived again, use the NAVCLR command. If the NAVTEX Mode is used infrequently, it is advisable
to clear the numbers, since the transmitting station my have already wrapped sequence numbers
back around to those you have stored.
