Q-Flex Satellite Modem Installation and Operating Handbook
6-82
The
Span
can be set to
Normal
, which limits the frequency span to that of the carrier, or
Super Wide
, which displays a frequency span of +/-25MHz centred on the carrier’s centre
frequency.
Super Wide
is useful for checking for adjacent interfering carriers.
Hi Definition
mode increases the number of samples by a factor of 4 but reduces the
graph refresh rate.
The reference level for the graph (i.e. the amplitude offset that appears at the top of the
graph) can be adjusted as can the amplitude resolution.
Persistence
leaves the spectrum to build up over time and is useful for identifying
transient signals such as intermittent interference.
LinkGuard™
is patented technology that monitors underneath the received carrier for
any interference, while on traffic. It is viewed using the same Rx Spectrum Monitor screen
as shown in
Figure 6-38
.
LinkGuard™
is explained in
Section 7.6
.
Figure 6-38 LinkGuard™ Signal-Under-Carrier Spectrum Monitor
6.2.10.2 Rx Constellaton Monitor
The Rx Constellation Monitor feature shown in
Figure 6-39
allows the modem to be used
as a spectrum analyser to view the received signal spectrum.