Nautel XR12, Руководство по установке

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XR12 Installation Manual Commissioning tasks
Issue 3.0 2009-07-15 Page 11-5
25. Turn off the audio signal generator and increase the output level of the audio signal
generator until a modulation depth of 100% is attained, as indicated on the modulation
monitor. The audio signal generator's output level should be +10 dBm.
26. Verify that the RF output's modulation envelope is acceptable.
27. If the program audio can be set to +10 dBm when 100% modulation is required, it is
recommended the
AUDIO GAIN
potentiometer on the interphase PDM driver PWBs be left
at the factory setting.
28. If the program audio cannot be set to +10 dBm when 100% modulation is required, the
AUDIO GAIN
potentiometer on the remote interface PWB must be reset as follows:
– Determine the program audio level (in dBm) that will be applied when 100% modulation
is expected. (It must be between 0 dBm and +12 dBm.)
– Set the audio signal generator's output to the level that will be applied by the program
audio when 100% modulation is expected.
– Adjust the
AUDIO GAIN
potentiometer on the remote interface PWB for 100%
modulation, as indicated on the modulation monitor.
29. Set the output level of the audio signal generator to zero (turned off).
30. Turn off the RF power stage: press and release the
RF OFF
switch. The
RF OFF
lamp will turn
on and the
RF ON
lamp will turn off.
31. Disconnect the audio signal generator from TB2-1(+) and TB2-3(-) on the remote interface
PWB.