Nokia NPM-6 Series Guide

CCS Technical Documentation
NPM-6/6X Series Transceivers
Issue 2 06/03 Copyright Nokia. All rights reserved.
Troubleshooting Instructions

NPM-6/6X Company confidential
Troubleshooting Instructions CCS Technical Documentation
Page 2 Copyright Nokia. All rights reserved. Issue 2 06/03
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CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 3
Table of Contents
Page No
RF Troubleshooting ....................................................................................................... 4
Introduction to RF troubleshooting .............................................................................4
RF Key component placement .....................................................................................5
RF Measurement points ...............................................................................................6
EGSM900 & GSM1800 Transmitter ............................................................................. 7
General instructions for Tx troubleshooting ............................................................. 7
Transmitter troubleshooting diagram ........................................................................ 9
Pictures of transmitter signals ................................................................................. 12
EGSM900, GSM1800 and GSM1900 Receiver .......................................................... 14
General instructions for Rx troubleshooting ........................................................... 14
Troubleshooting diagram for EGSM900 receiver................................................... 18
Troubleshooting diagram for GSM1800 receiver ................................................... 19
Troubleshooting diagram for GSM1900 receiver ................................................... 20
Synthesizer ................................................................................................................... 21
General instructions for synthesizer troubleshooting.............................................. 21
Synthesizer troubleshooting diagram ...................................................................... 22
Pictures of synthesizer signals................................................................................. 23
Baseband Troubleshooting........................................................................................... 25
BB Measurement points ............................................................................................25
Troubleshooting diagrams .........................................................................................27
FM Radio troubleshooting ........................................................................................... 48
FM Radio component layout .....................................................................................48
FM Radio troubleshooting diagram ...........................................................................50
Notes to "FM Radio troubleshooting diagram"....................................................... 50

NPM-6/6X Company confidential
Troubleshooting Instructions CCS Technical Documentation
Page 4 Copyright Nokia. All rights reserved. Issue 2 06/03
RF Troubleshooting
Introduction to RF troubleshooting
Measurements should be done using Spectrum analyzer with high-frequency high-
impedance passive probe (LO-/reference frequencies and RF power levels) and Oscillo-
scope with a 10:1 probe (DC-voltages and low frequency signals)
The RF-section is built around one RF-ASIC (HELGA N500). For easier troubleshooting,
this RF troubleshooting document is divided in to sections.
Before changing HELGA, please check following things: Supply voltages are OK and serial
communication is coming from baseband to HELGA.
Please note that the grounding of the PA module is directly below PA-module so it is dif-
ficult to check or change. Most RF semiconductors are static discharge sensitive! So
ESD protection must be taken care of during repair (ground straps and ESD soldering
irons). HELGA and PA are moisture sensitive so parts must be pre-baked prior to solder-
ing.
Apart from key components described in this document here are a lot of discrete compo-
nents (resistors, inductors and capacitors) which troubleshooting is done by checking if
soldering of the component is done properly (for factory repairs checking if it is missing
from PWB). Capacitor can be checked for shortening and resistors for value by means of
an ohmmeter, but be aware in-circuit measurements should be evaluated carefully.
Please be aware that all measured voltages or RF levels in this document are rough fig-
ures. Especially RF levels varies due to different measuring equipment or different
grounding of the used probe. When using RF probe usually a good way is to use metallic
tweezers to connect probe ground to PWB ground as close to measurement point as pos-
sible.

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 5
RF Key component placement
Figure 1: Component placement 1

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Troubleshooting Instructions CCS Technical Documentation
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RF Measurement points
Figure 2: Component placement 2

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 7
EGSM900 & GSM1800 Transmitter
General instructions for Tx troubleshooting
Kindly refer to the Service Software Section, Service Concept dagram (p.40)
Connect test jig to computer with DAU-9S cable or to FPS-8 Flash Prommer with XCS-4
modular cable.
Make sure that you have PKD-1 dongle connected to computers parallel port.
Connect DC power supply to module test jig with FLC-2 cable.
Attention: When repairing or tuning transmitter use external DC supply with at
least 3A current capability. Set the DC supply voltage to 3.9V and set the jumper con-
nector on test jig to "bypass" position.
Connect a RF-cable to the module test jig (MJS-49) RF connector to and to measurement
equipment or at least 10dB attenuator, otherfwise the PA may be damaged. Normally
Spectrum analyzer is used as measurement equipment.
Attention: Normally Spectrum analyzer maximum input power is +30dBm. It is recom-
mended to use 10dB attenuator on Spectrum analyzer input to prevent damage.
Set the phone module to test jig and start Phoenix service sofware
Initialize connection to phone. (use FBUS driver when using DAU9S and COMBOX driver
when using FPS-8)
Select product from the menu
File -> Choose product -> NPM-6
From toolbar set operating mode to "Local"
Activate RF controls window from the menu
Maintenance -> Testing -> RF Controls
From the RF controls window
- Select band "EGSM900" or "GSM 1800" or "GSM1900" (Default = "EGSM900")
- Set Active unit to "Tx" (Default = "Rx")
- Set Operation mode to "Burst" (Default = "Burst")
- Set Tx data type to "Random" (Default = "All1")

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Troubleshooting Instructions CCS Technical Documentation
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- Set Rx/Tx channel to 37 on EGSM900 band or 700 on GSM1800 band or 661 on
EGSM1900 (Defaults)
- Set Tx PA mode to "Free" (Default)
- Set power level to 5 (Default = 19) on EGSM900 or to 0 (Default = 15) on GSM1800 or
GSM1900

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 9
Transmitter troubleshooting diagram
Figure 3: Transmitter troubleshooting
Check output signal level:
TX signal found ?
Yes Tune
dead
start TX power level
Tune Tx DAC values
No
PA & ant switch
TX troubleshooting TX OK
+32...+33dBm @897.4 MHz (GSM900)
+29...+30dBm @1747.8 MHz
(GSM1800 & GSM1900)
OK ?
Check
all power
levels,
OK ?
TX power
levels,
OK ?
No
Yes
No Check output signal
on 500 MHZ span
Signal found on
incorrect frequency ?
Yes Synthesizer
troubleshooting
Check with RF probe
signal level on
PA input >=0dBm (*
OK ?
Yes
HELGA
troubleshooting
No
Yes
tuning and check
tuned RAC values:
Highest level~700...900
Lowest level ~190...210
Base levle ~160...190
Major differences ?
Check with oscilloscope:
PA ctrl voltage
>1.5V peak OK ?
No
troubleshooting
No
Check control loop
components
OK ? Replace HELGA
*(When 1kOhm passive probe is used,
correct the measurement result by +26dB
Replace
faulty
component(s)
Yes
Yes
Yes
Yes
(EGSM900

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Figure 4: HELGA IC troubleshooting
HELGA
troubleshooting
Baseband
troubleshooting
Synthesizer
troubleshooting
Check with oscilloscope:
-TXI/TXQ signals
--VR1, VR2, VR4, VR5, VR6 = 2.8V
-VrefRF01 = 1.35 V
-HELGA serial interface
-TXP & TXC signals
OK ?
No
Check with RF probe:
-4G VCO out signal
- 3589.6 MHz (GSM900)
-3495.6 MHz (GSM1800)
- 3760 MHz (GSM1900)
Level >-10dBm (*OK ?
No
dead
Replace HELGA
Yes
Check modulator
output components
OK ?
Replace
faulty
component(s)
*(When 1kOhm passive probe is used,
correct the measurement result by +26dB
Check with RF probe:
-4GVCO out signal
-3589.6MHz (EGSM900)
-3495.6 MHz (GSM1800)
-3760 MHz (GSM1900)
L
e
v
e
l >-1
0d
Bm

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 11
Figure 5: PA and Antenna Switch troubleshooting
PA& ant switch
troubleshooting
Yes
Check with RF probe
signal level on
PAinput >=0dBm (*
OK ?
Yes
Replace
ant. switch
Yes *(When 1kOhm passive probe is used,
correct the measurement by +26dB
Check with
oscilloscope:
-VANT_1 (GSM900)
-VANT_2 (GSM1800)
-VANT_3 (GSM1900)
OK ?
Check with
oscilloscope:
-VBATT ~4V
- VTXB = 2.8 V pulsed
- VTxLO_GSM = 0V (GSM900)
OK ?
Check
VANT lline components
OK ?
Replace
PA
Replace
HELGA
Replace
faulty
component(s)
Check components
around PA
OK ?
Replace
faulty
component(s)
Yes
Yes
Yes
No
No
No
No
-VANT_1 (EGSM900)
-VANT_2 (GSM1800)
-VANT_3 (GSM1900)
(EGSM900)

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Troubleshooting Instructions CCS Technical Documentation
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Pictures of transmitter signals
Figure 6: Transmitter signals
TXI
VPCTRL _900 power level high at R703/C703
VPCTRL_1800/1900 power level high at R704/C704_
VPC
TX I/Q at R516/517 power level high Random data
VANT_1 / EGSM900 TX at C804
VANT_2 / GSM1800 TX at C835
VANT_3 / GSM1900 TX at C805 OV
( no signal/ Flatline on Oscilloscope screen)
VANT_1,VANT_2,VANT_3
VTXB_900 at C713
VTXB_1800_1900 at C714 TXP at J504
200mV/div 100us/di
v
1200mV/div 100us/div
500mV/div 100us/div 500mV/div 100us/div
1
500mV/div 100us/div 500mV/div MTB 100us/div

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 13
Figure 7: TX OUT signal
Tx out signal, 900 band, burst mode, channel 37
A_wr i t eB_bl ank
CENTER 897. 400 MHz SPAN 2. 000 MHz
2. 0 s
SWP
100 kHz
VBW
100 kHz
RBW
10dB/
REF 4 1 . 0 d Bm ATT 4 0 d B
GS MP OW Tue Sep 25 13: 48: 59 2001
REF OF S
11. 0 dB

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Troubleshooting Instructions CCS Technical Documentation
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EGSM900, GSM1800 and GSM1900 Receiver
General instructions for Rx troubleshooting
Connect test jig to computer with DAU-9S cable or to FPS-8 Flash Prommer with XCS-4
modular cable.
Make sure that you have PKD-1 dongle connected to computers parallel port.
Connect DC power supply to module test jig with FLC-2 cable.
Set the DC supply voltage to 6V (test jig has internal voltage regulator of output volt-
age 4V).
Connect an RF-cable to the module test jig (MJS-49) RF connector and to RF signal gen-
erator.
Set the phone module to test jig and start Phoenix service sofware.
Initialize connection to phone. (use FBUS driver when using DAU9S and COMBOX driver
when using FPS-8)
Choose product from the menu
File -> Choose product -> NPM-6
From toolbar set operating mode to "Local"
Activate RF controls window from the menu
Maintenance -> Testing -> RF Controls
From the RF controls window:
- Select band "EGSM900", "GSM 1800" or “GSM1900” (Default = "EGSM900")
- Set Active unit to "Rx" (Default = "Rx")
- Set Operation mode to "Burst" (Default = "Burst")
For continuous mode:
- Set Operation mode to "Continuous"
- Set AGC to "12: FEG_ON + DTOS_ON + BB_30=Vgain60” (maximum gain setting used
in normal mode)
(Default = "14: FEG_ON + DTOS_ON + BB_42=Vgain72")

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 15
- Set Rx/Tx channel to 37 on EGSM900 band, 700 on GSM1800 band or 661 on
GSM1900 (Defaults)
Apply 942.46771 MHz (channel 37 + 67.710 kHz offset), 1842.86771 MHz (channel 700
+ 67.710 kHz offset) or 1960.06771 MHz (channel 661 + 67.71 kHz) –90 dBm signal to
the RF-connector (remember to compensate for cable attenuation).
Measuring with an oscilloscope on "RXI" or "RXQ" following screens should be seen on a
working EGSM900 , GSM1800 or GSM1900 receiver:
Figure 8: RX I/Q signal ,burst mode, input level –90dBm.
Figure 8, “RX I/Q signal ,burst mode, input level –90dBm.,” on page 15: Receiver I or Q
burst mode signal (channel 37) measured from testpoint RXI or RXQ with 942.467 MHz
signal, input level –90dBm at RF-connector.
Correct signal amplitudes approximately:
• EGSM900~170mVpp
• GSM1800~140mVpp
• GSM1900~160mVpp
Signal part frequency 67.7kHz sine.

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DC level of signal part is 1.35V. DC level can variate about +/-100mV between I and Q
signals and between different bands as well.
Figure 9: GSM1900 RX I or Q signal (trace2), burst mode.
For GSM1900 receiver burst mode I or Q signal at ch 661 with input signal
1960.067MHz, level –90 dBm at RF-connector.
Trace2: With wider time scaling both monitoring and own RX bursts are seen, 1st burst
(shorter) is monitoring and 2nd burst (longer) is own RX burst.
Trace1: External LNA VCC supply voltage at burst mode, input level –90 dBm. Measured
from testpoint LNA_VCC.

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
Issue 2 06/03 Copyright Nokia. All rights reserved.. Page 17
Figure 10: RX I&Q, phase difference 90 deg between signals.
Figure 10, “RX I&Q, phase difference 90 deg between signals.,” on page 17:
Detailed view of EGSM900 continuous mode RX I and Q signals measured from
testpoints RXI and RXQ simultaneously.
Used channel 37, input signal 942.467 MHz, level –90 dBm at antenna port, AGC setting
12.
Phase difference should be 90 degrees between RX I and Q signals at all bands.

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Troubleshooting Instructions CCS Technical Documentation
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Troubleshooting diagram for EGSM900 receiver
Phone in “Continuous” mode, AGC setting “12”
Figure 11: EGSM900 receiver troubleshooting
No
No
Yes
Yes
NoNo
Yes
No
Yes
NoYes
Yes
Yes
Apply –90dBm
942.46771MHz signal
from generator to anten-
na connector
Oscilloscope at RX_I
Signal 700mVpp
DC offset 1.35V***
Frequency 67.7kHz
No
Change ge-
nerator level
to –50dBm
Spectrumanalyzer
Antenna Switch
outputs, GSM900
–88 dBm
Spectrumanalyzer
Antenna Switch
input
–84 dBm
Oscilloscope
VR1,3...6 2.7V
Check HELGA serial
interface
(burst mode)
Synthesiszer trou-
bleshooting
Spectrumanalyzer
4G VCO out
3769.6MHz
∼–30 dBm (*
Oscilloscope
VANT_1...3 0V Oscilloscope :
Check HELGA
serial interface
(burst mode)
Check HELGA
N500
Check Base-
band
* Spectrumanalyzer
reading with 1 kohm
passive probe (right val-
ue add +34 dB)
All spectrumanalyzer reading
values are measured with
2.5 kohm passive probe (use
tweezers to connect the
probe ground to the nearest
PWB ground). Reading value
is represented without
+34 dB compensation.
900RX chain
functional
Check C831,
L811
Check Antenna
switch
Z800
Spectrumanalyzer
HELGA inputs
GSM900
–89 dBm
Check L809
L810
Check Base-
band
No
Yes
Yes
Check HELGA
N500
* ** DC–level of RXI/RXQ in
continuous mode will decrease
slowly.
The original level can be resto-
red by rewriting gain set.
Spectrumanalyzer
Antenna Switch
outputs,EGSM900
-88dBm
EGSM90
0
-89dBm

CCS Technical Documentation Troubleshooting Instructions
Company confidential NPM-6/6X
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Troubleshooting diagram for GSM1800 receiver
Phone in “Continuous” mode, AGC setting “12
Figure 12: GSM1800 receiver troubleshooting
Yes
No
Yes
No
Yes
Yes
Yes
NoNo
Yes
Yes
NoNoYesNoYes
Apply –90dBm
1842.86771MHz signal
from generator to anten-
na connector
Oscilloscope at RX_I
Signal 140mVpp
DC offset 1.35V ***
Frequency 67.7kHz
Change ge-
nerator level
to –50dBm
Spectrumanalyzer
Antenna switch out-
puts,
1800 LNA out
–61 dBm
Spectrumanalyzer
Antenna Swithc input
-84 dBm
GSM1800 RX chain
functional
Oscilloscope
VR1,3...6 2.7V
Check HELGA serial
interface
(burst mode)
Check C838, C839,
L821. L 872,
C836, C837,
V801
Oscilloscope
VANT_1...3 0V Oscilloscope
Check HELGA se-
rial interface (burst
mode)
Check HELGA
N600
Check Base-
band
* Spectrumanalyzer
reading with 1 kohm
passive probe (right val-
ue add +26 dB)
All spectrumanalyzer reading
values are measured with 1
kohm passive probe (use
tweezers to connect the
probe ground to the nearest
PWB ground). Reading value
is represented without +26
dB compensation.
Check C831,
L811
Check Antenna
Switch Z800
Spectrumanalyzer
HELGA inputs
GSM 1800
–88 dBm
Check Base-
band
No Synthesiszer trou-
bleshooting
Spectrumanalyzer
4G VCO out
3769.6MHz
∼–30 dBm (*
Yes
Check HELGA
N500
* ** DC–level of RXI/RXQ in
continuous mode will decrease
slowly.
The original level can be resto-
red by rewriting gain set.
N500
Check Helga
N500

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Troubleshooting diagram for GSM1900 receiver
Phone in “Continuous” mode, AGC setting “12
Figure 13: GSM1900 receiver troubleshooting
Yes
Yes
Yes
Yes
NoNo
Yes
Yes
NoNoYesNoYes
Apply –90dBm
1842.86771MHz signal
from generator to anten-
na connector
Oscilloscope at
RX_I /RXQ
Signal 160mVpp
DC offset 1.35V ***
Frequency 67.7kHz
Change ge-
nerator level
to –50dBm
Spectrumanalyzer
Antenna Switch out-
put, GSM1900
–88 dBm
GSM1800 RX chain
functional
Spectrumanalyzer
4G VCO out
3685.6MHz
∼–30 dBm (*
Oscilloscope
VANT_3 2.7VV
VANT_1/2 0V
Oscilloscope
LNA_VCC 2.6V
LNA_P 0 V
Oscilloscope
Check HELGA se-
rial interface (burst
mode)
Check HELGA
N500
Check Base-
band
Check C831,
L811
* Spectrumanalyzer
reading with 1 kohm
passive probe (right val-
ue add +26 dB)
All spectrumanalyzer reading
values are measured with 1
kohm passive probe (use
tweezers to connect the
probe ground to the nearest
PWB ground). Reading value
is represented without +26
dB compensation.
Spectrumanalyzer
Antenna Switch input
–84 dBm
Spectrumanalyzer
HELGA inputs
GSM1900
–78 dBm
Check Antenna
switch Z800
Spectrumanalyzer
RX_SAW_out
–90 dBm Check Baseband
Oscilloscope
VR1,3...6 2.7V
Check HELGA serial
interface
(burst mode)
Check Baseband
Yes
Check HELGA
N500
Yes
Check V802,
C826, Z802,
C829, C8097,
C808
Oscilloscope
VR1,3...6 2.7V
Check HELGA serial
interface
(burst mode)
Yes
Check Baseband
Synthesiszer trou-
bleshooting
Check HELGA
N500
* ** DC–level of RXI/RXQ in
continuous mode will decrease
slowly.
The original level can be resto-
red by rewriting gain set.
Z806