Specifications

7.4.7 Operating on the Wrong Sideband
In AMTOR operation it is important to be operating on the correct
sideband, otherwise other stations will not be able to copy you. If
you find a station operating on the wrong sideband, you can reverse
your receive sense with the RXREV command.
Similarly, if someone tells you that you are on the wrong sideband,
you can correct your transmit signal sense with the TXREV command.
See the Command summary for more information on these commands.
7.5 Monitoring ARQ AMTOR Contacts with ALIST
Use the "ALIST" command to monitor ARQ traffic flowing between two
stations linked in an ARQ contact. Your PK-900 will try to
synchronize with whichever of the two linked ARQ stations is the
Information Sending Station at the moment.
ARQ Listen operation does not give you error detection or error
correction; your PK-900 is not one of the two stations locked to
each other. If the other two stations are enjoying a good link,
you'll probably get good copy from that link.
Your PK-900 will not print a block of data if that block contains
the same information as the previous block. If the "ISS" (Information
Sending Station) is repeating the same block, you won't print it
twice, unless you receive an error. If the stations you're monitoring
are sending error and RQ codes and repeating blocks of characters
across their link, you may see some repeated character blocks. If
they're having link problems, the data on your screen can look very
strange indeed, although the two synchronized stations are getting
error-free copy.
7.6 AMTOR MailDrop Operation
The PK-900 allows AMTOR as well as Packet access to the MailDrop.
Messages that originate in Packet can be accessed remotely in AMTOR
and messages that originate from a remote AMTOR station can be
accessed by Packet users of your MailDrop. This section of the manual
talks about basic AMTOR mailbox operation. Section 7.7 will discuss
how to pass message traffic from AMTOR to Packet and vice versa.
Make sure that you understand MailDrop Operation in Chapter 5 and the
basic AMTOR operation described earlier in this chapter before putting
your AMTOR MailDrop on the air.
7.6.1 Special Operating Considerations
The AMTOR MailDrop has been designed with a "Watchdog" safety feature
so that it may perform safely without constant attention. If a remote
station is linked with your AMTOR MailDrop and no traffic is passed
for 5 minutes, the link will drop and your transmitter will shut off.
At this time however, the legality of unattended operation below 30
MHz is uncertain for US amateurs. US amateurs must be sure to always
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