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CCS Technical Documentation
NSB-9 Series Transceivers
Troubleshooting Instructions
Issue 1 04/03 Nokia Corporation
NSB-9
Troubleshooting Instructions CCS Technical Documentation
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Page 2 Nokia Corporation Issue 1 04/03
NSB-9
CCS Technical Documentation Troubleshooting Instructions
Table of Contents
Page No
RF Troubleshooting ....................................................................................................... 4
Introduction ..................................................................................................................4
EQUIPMENT NEEDED:.......................................................................................... 4
USEFUL HINTS ....................................................................................................... 4
TROUBLESHOOTING IN CASE OF RF TUNING FAIL ........................................5
Channel Select Filter Calibration .............................................................................. 5
RX Calibration .......................................................................................................... 5
RX AM Suppression Calibration .............................................................................. 5
RX Band Filter Response Compensation.................................................................. 5
TX Power Level Tuning............................................................................................ 5
TX IQ Tuning............................................................................................................ 5
TX 850 Troubleshooting ..............................................................................................6
Phoenix commands ................................................................................................... 6
TX1900 TROUBLESHOOTING ................................................................................9
Phoenix commands ................................................................................................... 9
RX850 troubleshooting ..............................................................................................12
Phoenix commands ................................................................................................. 12
RX1900 Troubleshooting ..........................................................................................15
Phoenix commands ................................................................................................. 15
Figures of signals and voltages in testpoints .............................................................18
FM Radio Troubleshooting ........................................................................................35
Introduction ............................................................................................................. 35
EQUIPMENT NEEDED......................................................................................... 35
FM RADIO SCHEMATICS ......................................................................................36
FM Radio layout...................................................................................................... 39
REFERENCE MEASUREMENT RESULTS ........................................................ 42
Baseband Troubleshooting........................................................................................... 45
PWB Test points ........................................................................................................45
Troubleshooting steps ................................................................................................51
Main troubleshooting tree ..........................................................................................53
Phone is dead .............................................................................................................55
Flash faults .................................................................................................................56
Phone is jammed ......................................................................................................58
Charging fault ............................................................................................................60
SIM card fault ............................................................................................................61
Audio faults ...............................................................................................................62
Display faults .............................................................................................................70
Keypad faults .............................................................................................................72
Flip faults ...................................................................................................................76
FM Radio doesn't work .............................................................................................78
Issue 1 04/03 Nokia Corporation Page 3
NSB-9
Troubleshooting Instructions CCS Technical Documentation
RF Troubleshooting
Introduction
This document describes the methods of RF troubleshooting for Iris NSB-9 transceiver.
Fault finding charts of the most common fails are included in this document. Arrows are
marked with (OK) and (NOT OK), respectively. Measurement equipment is marked as:
DMM Digital Multimeter
OSC Oscilloscope
SA Spectrum Analyzer
Figures of typical signals and voltages at each testpoint are described in Chapter 8.
Location of testpoints are described in Chapters 9 and 10.
EQUIPMENT NEEDED:
NSB-9 module jig MJS-48, power and DAU-9S cables
DC power supply 3.9 VDC >3A
Radio Communication Tester with GSM850/1900 option
Spectrum analyzer and probe with frequency range up to 4 GHz
Digital multimeter (DMM)
Oscilloscope with 10:1 probe
PC with Phoenix software
USEFUL HINTS
Sometimes it is difficult to get reliable measurement results at high frequencies
(500...4000 MHz) because of probe properties etc. If measurement results of faulty
phone don't correspond to the results shown in this document it may be useful to mea-
sure a reference phone and finally, compare the results.
Special attention shall be paid with internal antenna. Visual inspection of antenna mod-
ule (shape of radiator metal) is needed to verify that antenna is GSM850/1900 antenna -
not GSM900/1800 used in similar European product. Both antennas behave very simi-
larly in MJF-32 jig so it may be impossible to distinguish them by doing measurements
over air interface.
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NSB-9
CCS Technical Documentation Troubleshooting Instructions
TROUBLESHOOTING IN CASE OF RF TUNING FAIL
Channel Select Filter Calibration
Calibration is done using internal calibration circuit (UEM sends and receives a test sig-
nal to/from Hagar). VCO (G650), RX-bandfilters (Z501, Z551) and TX-filter/balun (Z700,
T700) don't have any effect to the Channel Select Filter Calibration. Instead, baseband
shall be functional (=VCTCXO G660 is running). Any failure in Hagar, its supply voltages
or RX/TX IQ-lines may cause this calibration to be failed.
If baseband works and there are not any visible cause around Hagar (missing or broken
components etc.), Hagar shall be replaced at first place.
RX Calibration
The most probably reason for this is lack of gain in receiver chain. Check rx chain accord-
ing to RX850/1900 fault finding charts. In GSM850 RX, components Z520, V500 and
Z501 should be checked. In GSM1900 RX, components Z520, V550 and Z551 should be
checked.
If signal seems to pass rx chains with adequate gain, VCO function shall be checked. It is
also possible that signal passes rx chain to Hagar and VCO is functional but signal
doesn't appear in RX IQ-lines. In this case, Hagar shall be replaced.
RX AM Suppression Calibration
RX AM Suppression Calibration limits (LOPI, LOMI, LOPQ and LOMQ) are so wide that the
calibration results can't exceed the limits. Instead, RSSI value measured after tuning may
be too high. Also in this case, replacing Hagar may improve the result.
RX Band Filter Response Compensation
If RX Calibration results are ok but this compensation fails, the most probably reason for
this is lack of gain (or too big gain) in receiver chain in some frequency. Check rx chain
according to RX850/1900 fault finding charts. Retest rx chain also in low and high chan-
nels. In GSM850 RX, components Z520 and Z501 should be checked. In GSM1900 RX,
components Z520 and Z551 should be checked.
TX Power Level Tuning
The most likely reason for this is lack of gain in transmitter chain. Check tx chain accord-
ing to TX850/1900 fault finding charts. In GSM850 TX, components Z500, L750, N700
and Z700 should be checked. In GSM1900 TX, components Z500, L750, N700 and T700
should be checked.
If signal seems to pass tx chains with adequate gain, VCO function shall be checked. It is
also possible that signal doesn't appear in TX IQ-lines. In this case, baseband shall be
checked.
TX IQ Tuning
TX IQ tuning fails, if IQ-spikes in the spectrum can't be tuned low enough. If replacing
Hagar doesn't help with this issue, VCO component (G650) and components around it
Issue 1 04/03 Nokia Corporation Page 5
NSB-9
Troubleshooting Instructions CCS Technical Documentation
shall be checked.
TX 850 Troubleshooting
Phoenix commands
RF Controls Band GSM 850 TX Burst mode
Channel 190 TX Power Level 10
TX PA Mode Free TX Data Random
Page 6 Nokia Corporation Issue 1 04/03
NSB-9
CCS Technical Documentation Troubleshooting Instructions
Figure 1: Fault finding chart, TX850
Check VCTCXO Check VCTCXO Start baseband
output signal at TP20 supply voltage at TP3 troubleshooting (UEM)
26 MHz OSC 2.78 VDC