falls below this value, the receiver states a receive level fault. To disable the level alarm, set
the threshold to a very low value, e.g. -120 dBm.Please note, that the threshold value refers
to the signal level, even if the receiver operates in a C/N measurement mode.
C/N Noise measurement --- With this parameter you select if the receiver shall perform a
plain input level measurement or a C/N measurement. A description of the C/N measurement
function of the receiver is given in chapter
5.3 C/N Measurement
. You may select one of the
following measurement modes:
OFF --- The receiver performs a plain level measurement. The
Readings
page shows
the input level in dBm.
C/N --- The receiver measures the signal / noise ratio. The
Readings
page shows the
C/N in dB.
C/N0 --- Like the C/N mode, but the receiver normalizes the C/N value to 1 Hz
measurement bandwidth. The
Readings
page shows the C/N0 in dBHz.
Frequency Tracking --- This parameter switches the the frequency tracking facility of the
receiver ON or OFF. A description of the frequency tracking facility is given in chapter
5.4
Frequency Tracking
.
Noise Measurement Frequency --- With this parameter you specify the frequency at
which the receiver shall measure the noise level at a certain interval. Like with the receive
frequency, the LO frequency settings made at the Setup page are taken into account also
for this frequency value.To get reasonable results with a C/N measurement, you should
consider the following:
1. The receiver does not change the LNB frequency band setting when it switches from
the level measurement to the noise measurement. The LNB probably would change it's
gain in this case. The noise measurement frequency hence must be in the same
frequency band as the receive frequency.
2. Measuring the noise level at the band edge may falsify the result due to the LNB's band
filter. The measured noise level may be too low in this case.
3. You should verify with a spectrum analyzer, that no signal disturbs the noise
measurement at the selected frequency.
Frequency Tracking Interval --- This parameter sets the interval on which the frequency
tracking procedure operates. The value is in seconds. Recommended settings are 15
seconds to tune the receiver quickly to a frequency you do not know precisely. For normal
operation a frequency tracking interval of one hour (3600 secs) is recommended.
Noise Measurement Interval --- This parameter defines the interval at which the receiver
inserts noise measurements in the C/N modes. The time is specified in seconds. 3600 secs
being one hour is a suitable setting in most cases.
Frequency Tracking width --- With this setting you limit the frequency offset the frequency
tracking procedure may apply to the nominal frequency. The frequency tracking never tunes
the receiver to a frequency outside the nominal fre/- this value, a frequency track
fault is generated if the tracked frequency reaches the limit.
Signal search enable --- Setting this parameter to ON enables the automatic signal search
function. With signal search enabled, the receiver searches the signal within the frequency
tracking range when the signal ist lost. Chapter
5.5 Signal search
describes this function
more detailed. 'SEARCH NOW' starts a search scan immediately, regardles of the enable
setting.
Analog output offset --- The beacon level shown as 0V at the analog output.
Signal search delay --- This parameter defines the time, the receiver waits after the signal
was lost until a search scan ist started. The valid range of this parameter is 0 .. 600 seconds.
Analog output scale --- The analog output scale (V/dB)
Spectrum Compensation --- With this parameter set to 'OFF', the receiver's level reading
is calibrated for a C/W signal. By selecting a modulation type for this parameter, the level
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