HF radio transmission
16 Manpack Transceiver 2110 series Reference Manual
Networks and scanning
A network is two or more stations that use the same frequencies and call system to
communicate. The frequencies are allocated by a government authority and enable the
network to maintain HF radio communication throughout the day and night.
The call system is the method the network uses to make and receive calls. For example,
in networks that use the Codan Selcall call system to make calls, the user enters the
address of the station they want to call, then selects the channel/mode on which to make
the call. In networks that use the ALE/CALM call system, the transceiver selects the best
channel/mode for the call.
The transceiver can be set to scan the channel/modes used by your network to detect
incoming calls. It is recommended that scanning is switched on when you are not using
the transceiver to communicate. This ensures that you can receive calls from stations in
your HF radio communication network.
The FED-STD-1045 ALE/CALM option
If you want to use the ALE/CALM call system to automate the selection of channels,
you must install the FED-STD-1045 ALE/CALM option in the transceiver. CALM
stands for Codan Automated Link Management.
The FED-STD-1045 ALE/CALM option enables the transceiver to test the signal
propagation qualities of your channels using soundings, and build a profile of each
channel’s suitability for use at different times of the day and night. The BER and SINAD
information collected during sounding activity is stored in the transceiver using a
24-hour period LQA database. With this information, the transceiver is able to select the
most suitable channel/mode for you when you make a call.
You are able to make global ALE ALL calls with this option.
CALM is interoperable with FED-STD-1045 ALE.
The MIL-STD-188-141B ALE option
The MIL-STD-188-141B ALE option includes the FED-STD-1045 ALE/CALM option.
It provides the capability to make ALE calls using ALL, ANY, Group Selective, NET,
and Wildcard address syntaxes. These calls connect one station to many stations at the
same time. The MIL-STD-188-141B ALE option also provides advanced LQA,
advanced messaging, and access to a Heard List.
The MIL-STD-188-141B ALE option is interoperable with FED-STD-1045 ALE and
MIL-STD-188-141B.
NOTE The MIL-STD-188-141B ALE option is available for the 2110 only.