Comnet MLS II MLSH041, Руководство по обслуживанию

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ALIGNMENT AND TROUBLESHOOTING PROCEDURES LBI-38425A
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1. Set the Signal Generator output for twice the microvolt reading obtained in the 12 dB
SINAD measurement.
2. Set the Range control on the Distortion Analyzer in the SET LEVEL position (1000
Hz filter out of the circuit), and adjust the input LEVEL control for a +2 dB reading
on the 30% range.
3. While increasing the deviation of the Signal Generator, switch the RANGE control
from SET LEVEL to distortion range until a 12 dB difference is obtained between
the SET LEVEL and distortion range readings (from +2 dB to –10 dB).
4. The deviation control reading for the 12 dB difference is the Modulation Acceptance
Bandwidth of the receiver. It should be more than ±6.5 kHz.
Service Check
If the Modulation Acceptance Bandwidth test does not indicate the proper width, refer to
the Receiver Troubleshooting Procedure.