Tait TB8100, User Manual

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174 Part H: Diagnosing
© Tait Electronics Limited December 2007
This test lets you see what signals are out there; it does not determine the
receiver’s sensitivity.
To measure signal levels
1. Select Diagnose > Reciter > Signal Level.
2. In the Center frequency box, specify the middle frequency of the band
you want to test. This can be any frequency within the receiver’s switching
range .
3. In the Channel spacing box, select a value from the drop-down list. This
specifies the size of the step from one frequency to the next. If this
corresponds to the channel spacing, you will measure signal levels of the
different channels in the band.
4. Under Peak hold , select On if you want the display to show the strongest
signal received on any pass.This means signals from infrequent users are
more likely to be included. Select Off if you want to see only the results of
the most recent pass.
5. On the toolbar, click Standby .
6. Click Start Test . The base station sets the receiver to a frequency, measures
the RSSI, increments the frequency by the value in the Channel spacing
box, measures its RSSI and so on for 101 steps below and above the center
frequency you specified. If a frequency lies outside the receiver’s lock range,
its RSSI is not displayed.
The graph displays the measured RSSI values and annotates the x-axis with
the correct frequency values.
Determining Synthesiser Lock Ranges
You can test the reciter’s synthesisers to determine the range of frequencies that
the receiver and the exciter can operate on. Use these tests to check that the
reciter is calibrated correctly for the channels that it will operate on.
The Clock source box indicates whether the reference frequency is internal
or external to the base station.
The bottom group of boxes with LEDs indicate the lock status of various parts
of the reciter in its current operation.
To test the exciter or receiver lock range
1. Select Diagnose > Reciter > Synthesisers.
2. Click Start Test in the exciter or receiver row.
The exciter or receiver checks all the channel frequencies in the band that
the base station is type-approved to operate in.