Philips 50 T Series, Руководство по обслуживанию

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Receiver Assembly Test
Chapter 8 - RF Bench Repair
7. Using an AC Coupler, connect the Preamplifier’s output to the input
of the Spectrum Analyzer. The AC Coupler prevents the Spectrum
Analyser input from receiving 21 V DC.
The Spectrum Analyser should be set as follows:
START frequency
400 MHz
STOP frequency 500 MHz
Resolution Bandwidth 100 kHz
Video Bandwidth 100 kHz
Reference Level -10 dBm
The Spectrum Analyser measurement must be:
Frequency 450 MHz
Level > - 32 dBm
If this measurement is correct, complete Receiver Assembly Test.
8. Remove the BNC connector from the Preamplifier input and connect
this cable to the Spectrum Analyzer.
The Spectrum Analyser measurement must be:
Frequency 450 MHz
Level > - 46 dBm
9. If this measurement is correct, replace the Preamplifier Board. If this
measurement is not correct, replace the Coax cable. If this does not
solve the problem, replace the Receiver Processor Board (503).
Receiver Assembly Test
1. Remove the flat cable and coax cable from the Receiver Assembly.
2. Pull out and turn over the Receiver Assembly and undo all 7 screws.
3. Lift up the top cover of the Receiver Assembly and connect the flat
cable again.