Rf Troubleshooting; Abbreviations In Fault Finding Charts; Introduction - Nokia NEM-4 Series Troubleshooting Instructions

CCS Technical Documentation

RF Troubleshooting

Abbreviations in fault finding charts

BB
DCS/PCN
PCS
EGSM
ESD
GPRS
HSCSD
LO
PA
PWB
PLL
RF
RX
SA
TX
UHF
VCO
VHF

Introduction

Two types of measurements have to be done for repair of the phone boards:
• RF measurements shall be done using a Spectrum Analyzer together with a high-fre-
quency probe. (Note, that signal will be significantly attenuated). Correct attenua-
tion can be checked by using a "good" phone board, for example.
• LF (Low frequency) and DC measurements shall be done with a an oscilloscope
together with an 10:1 probe.
Always make sure that the measurement set-up is calibrated when measuring RF param-
eters at the RF connector. Remember to include the correct losses in the module repair
jig and the connecting cable when realigning the phone.
Most RF semiconductors are static discharge sensitive. ESD protection must be taken
into account during repair (ground straps and ESD soldering irons).
Mjoelner RF ASIC is moisture sensitive. Therefore, Mjoelner RF ASIC must be pre-baked
prior to soldering.
Issue 1 09/2003
Company Confidential
Base band
GSM1800
GSM1900
Extended GSM900
Electro Static Discharge
General Packed Radio Service
High Speed Circuit Switched Data
Local Oscillator
Power Amplifier
Printed Wired Board
Phase Locked Loop
Radio Frequency
Receiver
Spectrum analyzer
Transmitter
Ultra High Frequency
Voltage controlled oscillator
Very High Frequency
Copyright  2003 Nokia Corporation
Company Confidential
NEM-4
RF Troubleshooting
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