Philips CT6558 Tuning Up Procedure & Operational Manual page 11

PHILIPS
Tuning Up procedure & Operational Manual
CPU
Trouble shooting to receiver circuit
1． We separate the failures in 3 parts: Logic failure, receiver failure and transmission failure. First we need define the
failure according to the failed item then we begin the analysis in detail.
2. Receiver key parameters include: RX LEVEL、 RX QUALITY、 MOBILE CALL、 FLATNESS、 TIME MASK、 PHASE
ERROR、FREQUENCY ERROR, etc.
2.1 Confirm the analyzer station has been set up：
a .Setup the right work condition of Agilent8960：Band: EGSM; Channel, Altitude of transmitter of the BS.
b. Power on radio, Connect the RF cable from 8960 to radio, setup right channel no. and RX altitude of debug
tool, same as 8960.
C. then using debug tool in RX mode, press 'measure' button to check whether the received signal is same as
input signal.
Test signal on a good radio to get reference signal when you don't know if the signal is right
Step1:Measure the received signal according to signal flowing chart.
Measure the signal with spectrum analyzer on 2001 to check if the input signal is right. If wrong signal was
detected it maybe U501 cold sold or part defect.
Measure the signal on pin12 of 7010 to check if the input signal is right. If wrong signal was detected it
maybe 2001 cold soldering, tombstone part, part missing or screwed part.
Revision :
Date :2004-9-7
Page No. : Page 11 of 11
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Receiver