Nokia NEM-4 Series Troubleshooting Instructions Download Page 125

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CCS Technical Documentation

RF Troubleshooting

Company Confidential

NEM-4

Issue 1 09/2003



2003 Nokia Corporation.

Page 6(b)-121

Company Confidential

The Spectrum Analyzer now shows a plot like this:

Press Save and Continue in order to continue with the next band.

Note: The optimal values for I and Q Offset and Amplitude and Phase Difference vary
from phone to phone.

Ref Lvl

35 dBm

Ref Lvl

35 dBm

RBW

3 kHz

VBW

3 kHz

SWT

3 s

RF Att

30 dB

30 kHz/

Center 897.4 MHz

Span 300 kHz

27.5 dB Offset

1MA

Unit

dBm

-60

-50

-40

-30

-20

-10

-65

Marker 1 [T1]

33.40 dBm

897.33229000 MHz

1 [T1] 33.40 dBm

897.33229000 MHz

2 [T1] -20.35 dBm

897.40000000 MHz

3 [T1] -27.60 dBm

897.46771000 MHz

Date: 14.JAN.2002 13:23:02

Summary of Contents for NEM-4 Series

Page 3: ...ing 35 Memory Troubleshooting 37 MMC Troubleshooting 38 VIBRA 40 ZOCUS 41 UI Troubleshooting 41 UI Troubleshooting cases 41 Keymat Backlight 42 Keyboard 43 Display blank 44 Backlight does not turn on 45 FM Radio Troubleshooting 46 FM Radio component layout 46 FM Radio Troubleshooting diagram 48 RF Troubleshooting 53 Abbreviations in fault finding charts 53 Introduction 53 RF Key component placemen...

Page 4: ...ructions for Synthesizer Troubleshooting 86 26 MHz reference oscillator VCXO 90 VCO 90 Fault finding chart for PLL Synthesizer 91 PLL Block diagram 92 PLL power supply 93 Frequency lists 96 Phoenix tuning 99 RF tuning after repairs 99 RX Calibration incl VCXO Calibration 99 RX AGC limits 104 RX Band Filter Response Compensation 107 TX Power tuning 114 TX I Q Tuning 116 Bluetooth Troubleshooting 13...

Page 5: ...chapter in service manual Laboratory power supply with current indicator Oscilloscope Digital multimeter General guidelines If the device cannot be turned on by any means see dead device trouble shooting Current consumption missing consumption gives an idea whether the device is able to start up Dropping supply voltage or very large current consumption indicates a short circuit Check whether the c...

Page 6: ...possible short circuit to ground signal low or to supply voltage signal high Note that if a prob lem is not found from any visible contact component it can be under CSPs where the sig nal is connected Care must be taken when assembling and disassembling the transceiver Failure to do this may result in unnecessary damage to device Nominal current consumption NOTE Service tools need some amount of c...

Page 7: ...Troubleshooting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 a 5 Company Confidential Troubleshooting paths Dead or jammed device Disassemble Check UI connector Replace UI module display display ...

Page 8: ...en Troubleshooting use these tips and follow the given Troubleshooting path Most common symptoms for audio problems Earpiece sound is missing Headset is not recognized Microphone is not working Volume cannot be adjusted Ringing tones does not work Audio volume too low Radio does not work IHF sound is missing Headset sound is missing MP3 AAC play does not work If the symptom is something like above...

Page 9: ...ade Phone does not find signal Call is often dropped See RF Troubleshooting ASIC is changed ASIC s can be changed only at a defined service level UEM changed If UEM is changed baseband calibrations should be made New IMEI must be pro grammed also ZOCUS calibration is not necessary UPP_WD2 changed IMEI must be reprogrammed ZOCUS changed Zocus must be re calibrated Test points Table 1 Test points in...

Page 10: ...sh WE J567 ADSP C3 ADSP Flash CE1 J564 ADSP GPIO2 J565 ADSP GPIO3 J312 FLASH _CE D310 J315 FLASH CLK D310 D311 D313 J311 FLASH _CE D311 J313 FLASH _CE D313 J314 SDRAM CLK D312 J197 GPIO13 Keyboard matrix ROW0 J196 GPIO12 Keyboard matrix ROW1 J179 GPIO16 Keyboard matrix COL4 J116 GPIO30 Keyboard matrix COL5 J119 GPIO15 Keyboard matrix ROW3 J118 GPIO14 Keyboard matrix ROW2 J176 GPIO18 Keyboard matri...

Page 11: ... J186 LCD signal J187 LCD signal J188 LCD signal J189 LCD signal J190 LCD signal J191 LCD signal J113 LCD signal J114 LCD signal J905 UEM DLIGHT Display LED driver control J404 SIM Data J405 SIM Clock J406 SIM Reset J913 MMC CMD J914 MMCDAT0 J577 N470 Dir3 J579 N470 Dir2 J576 N470 A1 J578 N470 A3 J593 N470 A2 J910 N470 EN2 J911 N470 EN1 J568 USB PU J569 USB D J575 USB D J398 VBAT After current sen...

Page 12: ...re is able to run and thus the watchdog of UEM can be served Selftest functions are executed when the phone is powered on and if one or more selft est functions fail the message Contact Service is shown on the display MCU selftest cases can be split into two categories The ones that are executed during power up and the ones that are executed only with a PC connected These test and the items includ...

Page 13: ...he necessary steps are described below Phoenix error messages during flashing greatly help on defining what is wrong To be able to flash the device most device BB area components must function properly Flashing faults Measure FBUSTX line during flash programming is it 1 8V Change UEM No Yes Check BSI line Battery connector flex C239 Z383 R384 Yes Yes The phone does not set Flashbus TXD line high a...

Page 14: ...r message about sdram failure Wrong manufacturer ID and device ID No No Retest Flash informs about a failure during flashing No Check flash0 bypass caps check Vpp connection to flasher Check Vpp resistor 4 7k Ok Change flash0 Yes Yes Activity in sdram clk J108 pad No Change UPP_WD2 Yes Voltages VmemA and VioA ok No EM troubles No Secondary receive fail or Algorithm send failed message Change UPP_W...

Page 15: ...Copyright 2003 Nokia Corporation Page 6 a 13 Company Confidential ADSP flashing Troubleshooting ADSP flash environment consists of ADSP ADSP flash EMIF external memory interface communication interfaces USB and UPP UEM ADSP flash protecting control and power supplies for ADSP and ADSP flash ...

Page 16: ...is may caused by SW problem UPP_WD2 problem Not server by SW UEM or memory malfunctions The following tests are recommended General power checking Clocks Memory testing Serial Interface If there is something wrong in BSI line the device seems to be dead after the power key is pressed However the regulators of the device are on a few seconds before the power down This mode can easily be detected fr...

Page 17: ...ne disassem bly use module jig MJS 8Q Short circuit in Vbatt1 3 Vbattbb or Vbattihf lines Try to find short circuit Check components which are able to short cuircuit these lines filtering components etc Vbatt1 3 Vbatbb Vbattihf meas from C301 C302 C313 PURX J125 1 8V Check Vcorea and Vmema voltages OK See next page Check sleep clock J124 32 768Khz Meas from C197 OK Check B190 C196 C197 VBATHF or B...

Page 20: ...NEM 4 Company Confidential BB Troubleshooting CCS Technical Documentation Page 6 a 18 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Audio Power Troubleshooting ...

Page 21: ... to UEM which then supplies it to UPP_WD2 Bluetooth module and FM radio chip The third oscillator generates 12MHz clock for ADSP and AIC UPP_WD2 uses the system clock to generate various clocks for different purposes Figure 1 Clock diagram System clock can be measured from the lower pad of capacitor C171 This clock should be running when phone is on In SLEEP mode the VCXO is off UEM generates low ...

Page 22: ... B190 is oscillating at 32 768kHz frequency If not change B190 If ok measure SleepClk from test point from capacitor C521 Frequency should be the same 32 678kHz see Figure 2 Sleep clock on page 20 below If not change UEM Figure 2 Sleep clock ADSP Clock 12MHz sine wave can be measured from oscillator B550 Charging checking Use the BL5 C battery and JBV 1 MJF 26 calibration set to test charging NOTE...

Page 23: ...ial NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 a 21 Company Confidential 900mA Remove and reconnect battery and charger few times before you start to measure device This check ensures that the fault really exists Refer to Charging Troubleshooting ...

Page 24: ... BB Troubleshooting CCS Technical Documentation Page 6 a 22 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Figure 3 Charging Troubleshooting Check BL5 C Btemp BSI X606 R385 R404 Phoenix and JBV1 MJF26 X381 ...

Page 25: ...okia Corporation Page 6 a 23 Company Confidential Nothing happens when ACP 2 is connected Measure Vchar at C384 Is it 3 0Vdc Check F380 TVS V381 and L380 Check R191 is it OK Replace R191 and retest ACP 12 at C388 and C387 Is it F381 V383 and L381 Check R191 and Z190 Are they ok Replace R190 Z190 and retest ...

Page 26: ...tage and Charger current are calibrated Limits for calculated calibration values are as follows ADC offset over limits Inspect BSI line and components in it R385 Pull up resistor R220 If these are OK change UEM BSI Gain over limits Inspect BSI line and components in it R385 Pull up resistor R220 If these are OK change UEM Channel Low High ADC Offset 50 50 ADC Gain 26000 29500 BSI Gain 860 1180 Vba...

Page 27: ... current sense resistor R191 if calibration is not still successful change UEM Calibration can be checked using ADC readings Known voltages currents and resis tances are fed and read by ADC readings read values and known values can be com pared ADC reading Divided and scaled battery voltage Charger voltage Charger current BSI and Btemp val ues can be read by this tool Read values few times before ...

Page 28: ...heck that the backup battery is correctly mounted in the device before closing the cover Check with Phoenix that backup battery is OK Measure the voltage of backup battery Normal operation when the voltage is 2 0V Fully charged when the voltage is about 3 2V because of large internal imped ance voltage won t stay above 3 0V a long time after charging is disabled Enable backup battery charging star...

Page 29: ...al of the battery Monitoring of the BSI signal is done by a comparator inside UEM The threshold voltage is calculated from the battery size specifications The SIM interface is powered up when the SIMCardDet signal indicates card in This signal is derived from the BSI signal SW tries first to power up the SIM with 1 8 V If this doesn t succeed power up is repeated with VSIM switched to 3 V The data...

Page 30: ...6 a 28 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Figure 4 SIM Power Up Figure 5 SIM answer to reset Ch1 Vsim Ch2 Reset Ch3 Clock Ch4 I O Measured with 3Vsim SIM answer to reset CH1 SIM_CLK CH2 SIM_RST CH3 SIM_I O CH4 SIM_PWR Measure points SIM connector ...

Page 31: ...pany Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 a 29 Company Confidential Figure 6 SIM Clk 3 25MHz Remember to check the two PHOENIX test cases before changing UPP SIM_Clk_3 25MHz CH1 SIM_CLK Measure points SIM connector ...

Page 32: ...ds Replace connector Change UEM Check SIM connector Is it OK Check clean battery centre contact Verify BSI signal has a steady voltage Measure VSIM Is it 1 8 3 0V when SIM interface is powered up Measure VSIM resistance to GND Is it low Check C471 Is it OK Change VSIM decouple C471 Change SIM ASIP R496 Check Clk RST DATA at SIM connector Are the signals Check Clk RST DATA between UEM and the SIM A...

Page 33: ...nical Documentation BB Troubleshooting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 a 31 Company Confidential Audio Troubleshooting Figure 7 Audio routing window in Phoenix ...

Page 35: ...CCS Technical Documentation BB Troubleshooting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 a 33 Company Confidential Earpiece Check that holes are not coated ...

Page 39: ...ead or there is a soldering prob lem somewhere either under UPP or SDRAM There is a BB self test for testing SDRAM component quite thoroughly but the problem is that if SDRAM doesn t function properly one may not be able to run those tests as SDRAM is used during the device boot and selftest cannot be run if the device hasn t booted DEVICE may inform about being out of memory more often than it sh...

Page 43: ...oisiness is usually caused by the surrounding mechanics when the rotating mass has contact to it Vibra Malfunction Vibra is continuously on Vibra is noisy Vibra doesn t rotate Check the surrounding mechanics of the Vibra Is the Vibra jammed or its contact pads worn Is it Vibra component itself that makes noise Measure that C134 is pulsed down to zero while Vibra is switched on Check C134 C135 V132...

Page 44: ...g wrong with the UI function If the problem is due to the display or keymat PWB the whole UI module should be replaced However the earpiece maybe replaced see Audio Troubleshooting Read phone current consumption in Phoenix N N Check N301 and other components Replace component Y OK SW Error Reflash Replace damaged components and retest Read phone current consumption in Phoenix N N Check N301 and ot...

Page 45: ...tion Page 6 a 43 Company Confidential Keymat Backlight If the keymat backlight is non functional and the backlight driver voltage is generated correctly then there is either a problem with the connector or the UI module Note that it is possible for an LED to be non functional and for all other LEDs to still be working ...

Page 46: ...nfidential BB Troubleshooting CCS Technical Documentation Page 6 a 44 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Keyboard If keyboard doesn t work follow the Troubleshooting flow chart below ...

Page 47: ...Nokia Corporation Page 6 a 45 Company Confidential Display blank OK Change V101 Z130 Change UPPWD2 N Replace Display Display blank Y Check test points J113 J114 J185 J191 Y N Display ok OK Change V101 Z130 Change UPPWD2 N Replace Display Display blank Y Check test points J113 J114 J185 J191 Y N Display ok ...

Page 48: ...NEM 4 Company Confidential BB Troubleshooting CCS Technical Documentation Page 6 a 46 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Backlight does not turn on Figure 8 ...

Page 49: ...BB Troubleshooting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 a 47 Company Confidential FM Radio Troubleshooting FM Radio component layout Figure 9 Component placement Figure 10 Trace layout ...

Page 50: ...CS Technical Documentation Page 6 a 48 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Figure 11 FM radio block layout Components C001 and C002 are not shown in the picture Those components are placed near audio connector X002 ...

Page 51: ...Figure 12 FM Radio control window FM Radio Troubleshooting diagram Notes to FM Radio Troubleshooting diagram Use 1MHz 1X probe when measuring Audio and clock signals with oscilloscope Use active RF probe when measuring frequencies with spectrum analyzer Note 1 RF test signal parameters Amplitude A 67 0 dBm Carrier frequency fc 98 000 MHz Deviation f 75 kHz ...

Page 52: ...tial BB Troubleshooting CCS Technical Documentation Page 6 a 50 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Modulating frequency fm 1 000 kHz RF generator internal FM stereo mode R L pilot state ON ...

Page 53: ...udio from C162 and C163 Are both cases 1 kHz 0 5 0 8 Vp p Check V356 V357 L356 L357 C357 C358 C362 R359 R360 Test again with 87 5 and 108 0 MHz Measure audio from C162 and C163 Both OK Check C107 C108 C109 C117 L105 C367 C378 C379 L358 Measure signal from C162 C163 Is it 1kHz 0 5 0 8 Vp p Check R359 R360 V356 V357 L356 L357 C357 C358 C362 Measure signal from J103 J104 OK Check R164 R165 R166 R167 ...

Page 54: ...Corporation Issue 1 09 2003 Company Confidential Diagrams of FM radio signals Figure 14 Oscilloscope screen shot Audio output Signal 1 Audio output from PWB test points J103 and J104 with FM test signal volume 100 Signal 2 Audio output from FM radio pins 22 and 23 same as in C017 and C018 with FM test signal ...

Page 55: ...rom FM radio pins 3 and 4 the other ends of V500 and V501 with FM test signal RES BW 10 kHz VBW 10 kHz SWP 1 00 sec AT 0 dB REF 20 0 dBm LOG 10 dB CENTER 98 0000 MHz SPAN 300 0 kHz 71 03 dBm MKR 97 9280 MHz PEAK WA SB SC FS CORR 15 51 49 03 JUL 2002 SWEEP CONT SGL FREE RUN VIDEO LINE EXTERNAL SYNC CRD TV TRIG RES BW 10 kHz VBW 10 kHz SWP 20 0 msec AT 10 dB REF 0 dBm LOG 10 dB CENTER 196 450 MHz SP...

Page 57: ...ents 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 ...

Page 58: ...ment there are a lot of discrete com ponents resistors inductors and capacitors for which Troubleshooting is done by check ing if soldering of the component is done properly and checking if the component is missing from PWB Capacitors can be checked for short circuiting and resistors for value by means of an ohm meter but be aware in circuit measurements should be evaluated carefully In the follow...

Page 59: ...and can be measured either in the Mjoelner can or in the baseband can Arrows mark the measurement points inside the pictures Reference number Name Reference number Name N601 Mjoelner RF ASIC X602 RF Connector B601 26 MHz Xtal L801 Directional Coupler Z602 GSM1800 RX SAW V801 Detector Diode Z603 GSM1900 RX SAW Z601 Antenna switch Z604 EGSM RX SAW filter N801 Power Amplifier Z701 EGSM TX SAW filter ...

Page 60: ...ge 6 b 56 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Measurement points in the receiver Measurement points are indicated on the picture below Figure 3 Rx I and Q measurement points Figure 4 Rx measurement points at Rx SAW filters and Mjoelner RF ASIC ...

Page 61: ...1 09 2003 Copyright 2003 Nokia Corporation Page 6 b 57 Company Confidential Measurement points in the transmitter Measurement points are shown in the picture below Figure 5 Tx measurement points inside PA can bottom side of PWB Figure 6 Tx measurement points on the top side of PWB ...

Page 62: ...een RF frequency and DC All up and down conversion takes place in the RF ASIC named Mjoelner N601 Mjoelner RF ASIC also contains PLL and LNAs for all used bands A DC control section is included in to power and or control EGSM TX buffer detector and antenna switch The Mjoelner RF ASIC is controlled via a serial bus Mjoelner RF ASIC contains an integrated VCXO which uses an external 26 MHz Xtal No a...

Page 63: ...kia Corporation Page 6 b 59 Company Confidential Figure 8 RF frequency plan EGSM 925 960 MHz DCS 1805 1880 MHz PCS 1930 1990 MHz f f f 4 f 4 f f Mjoelner f 2 f 2 PLL 3420 3980 MHz I signal Q signal RX I signal Q signal TX PCS 1850 1910 MHz DCS 1710 1785 MHz EGSM 880 915 MHz XTal 1 1 1 2 LPRFCLK RFCLK 26 MHz ...

Page 64: ...filter 3 RFBUSX RFBUSDA RFBUSCLK Synth supply filter Ref clk set Rx supply filter VR6 VR5 VR3 VR4 RFCONV_0 9 VR2 VIO VCOSENSE VTXBH VTXBL VR2 VTXLOH VIO SELADDR GENIO6 VCXO supply filter VR7 LPR CLK buffer VCO supply filter DET SAW SAW PA Dir Coupler Ant Switch VBATTRF PCN PCS EGSM PW loop filter SAW VTX RX900 Buffer Balun SAW RX PCS TX EGSM RX TX RX PCN 3 PA_IDENT RX1800 RX1900 VR1A 5V 64 65 NDIV...

Page 65: ...gram below Values of voltages are given as nominal outputs of UEM Currents are typical values Figure 10 RF Power distribution diagram UEM VR1A 4 7V VR2 2 78V VR3 2 78V VR4 2 78V VR5 2 78V VR7 2 78V VIO 1 8V VREF01 1 35V VBAT Charge Pump Supply Vddcp 0 5mA TX Modulators 85mA Bias Vddtx 8mA Mjolner registers Vdddig 10uA VCXO Supply Vddxo 2 7mA BT Buffer 1mA RX LNA RX Mjoner BB Vddrxf 7mA Vddrxbb 30m...

Page 66: ...ding Start Phoenix Service Software Log in with your user ID Select File Alt F Manage Connections M FBUS Apply Close window Open the FBUS connection Select Scan Product Ctrl R Wait until phone information shows in the lower right corner of the screen Set operating mode to local mode Select Testing alt S RF Controls R Wait until the RF Controls window pops up Select Band GSM 900 or GMS 1800 or GSM ...

Page 67: ...1900 1960 067 MHz channel 661 67 710kHz offset and a power level of 80dBm to the RF connector remember to compensate for cable attenuation In RSSI reading click on Read now Measuring RX performance using SNR measurement Start Phoenix Service Software Open the FBUS connection Select Scan Product Ctrl R Wait until phone information is shown in the lower right corner of the screen Set operating mode ...

Page 68: ...t RX Operation mode Burst RX TX Channel 37 or 700 or 661 Select Testing alt S SNR Measurement N select Fast SNR Radio Button The setup should now look like this Choose respective band EGSM900 GSM1800 GSM1900 Press Start A window pops up e g for EGSM900 band Connect an external signal generator to the RF connector of the phone and set the gen erator as told in the window taking care for external ca...

Page 69: ...ct Ctrl R Wait until phone information shows in the lower right corner of the screen Set operating mode to local mode Select Testing alt S RF Controls S Wait until the RF Controls window pops up Select Band GSM 900 or GMS1800 or GSM1900 Active unit RX Operation mode Continuous RX TX Channel 37 or 700 or 661 Please refer to the fault finding chart for proper levels at different test points Measurin...

Page 70: ...hannel 37 or 700 or 661 AGC 14 Following picture should be seen on a working EGSM receiver Signal amplitude 1 25V DC offset 1 35V Frequency 67kHz Receiver fault finding Set up Phoenix as if doing RSSI measurements Ascertain which Rx band is faulty Refer to Rx fault finding flow chart Set signal generator frequency to 942 47MHz for EGSM 1842 87MHz for DCS 1800 or 1960 07MHz for PCS 1900 Set signal ...

Page 71: ...P Check SAW Output Mjoelner Input for band OK Check Mjoelner Voltage Supplies RFBUS lines All OK Refer to BB Fault Finding Replace Mjoelner Check Antenna Switch Test Point Signal OK Check PI Filter SAW Components OK Replace all 3 Components Replace SAW Filter Check Antenna Switch Cont lines Do they match the results in the table Replace Antenna Switch Check L701 L702 L703 OK Replace Inductor YES N...

Page 72: ...s diplexer EGSM900 input signals pass to GSM_Rx out put GSM1800 input signals pass to PCN_Rx output or PCS_Rx output depending on the control signal VANTH Cont2 From RX1 GSM output of the antenna switch the RX signal is routed in the inner layers of the PWB to the EGSM900 SAW filter Z604 From RX2 DCS output the GSM1800 RX signal is routed to the GSM1800 SAW filter Z602 From RX3 PCS output the RX G...

Page 73: ...ated LNAs provide the front end gains Each of the SAW filters has a single ended input and a balanced output which provides a balanced RX signal to the corresponding input of the Mjoelner RF ASIC The SAW filters have maximum insertion losses of 3 5dB EGSM900 4 0dB GSM1800 and 4 0dB GSM1900 RX paths of Mjoelner RF ASIC The balanced RX signal is amplified by the integrated LNA and the subsequent Pre...

Page 74: ...or to allow the transmitted signal to act as normal RF cable should be connected to measurement equipment GSM Test equipment Power meter Spectrum Analyzer or similar Be sure to use at least a 10 dB attenuator other wise the results may be incorrect Connect the phone to a PC with DAU 9S cable and dongle and follow the following instructions Set the mode switch to Local and connect the phone to a po...

Page 75: ...cy 897 4MHz for EGSM 1747 8MHz for PCN 1800 1880MHz PCS 1900 and set Span to 1MHz Set Amplitude of spectrum analyzer reference level to one that you can clearly see the transmit pulse according to the kind of test probe you are using Diagnose as per fault finding flow chart Note Be careful when selecting the operation mode if Continuous is selected prolonged transmission may damage the phone ...

Page 78: ...any Confidential RF Troubleshooting CCS Technical Documentation Page 6 b 74 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Figure 12 Mjoelner Can Tx Test Points TX Analog I Q Data C715 C716 ...

Page 79: ...CCS Technical Documentation RF Troubleshooting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 b 75 Company Confidential TXP TXC Lines during Transmission TXP TXC ...

Page 80: ...NEM 4 Company Confidential RF Troubleshooting CCS Technical Documentation Page 6 b 76 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential This page intentionally left blank ...

Page 81: ...oting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 b 77 Company Confidential Figure 1 EGSM TX Can Test Points TXP TXC Mask TXP TXC Power Control Loop On Baseband Generated Reference for EGSM Power Level 19 ...

Page 82: ...cumentation Page 6 b 78 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential VTXB_900 EGSM V802 Pre Amp Biasing Waveform Only Biases V802 for duration of TX Pulse EGSM Transmit Waveform Burst Power Level 19 Phone drew 140mA during Burst operation ...

Page 83: ...ed EGSM900 signal For easy error tracing it is important to know the signal path of the EGSM900 transmit ter The components can be grouped into blocks and drawn as shown below Note that the following picture shows both EGSM900 transmitter bottom and GSM1800 GSM1900 transmitter top EGSM Transmit Waveform Continuous Power Level 19 Was drawing over 600mA during continuous operation ...

Page 84: ...hrough the EGSM TX SAW fil ter balanced to single ended a 900MHz buffer and a 5 db pad to the PA EGSM input EGSM900 TX path of the Power Amplifier PA The PA EGSM900 part has a maximum output power of app 35dBm Voltage supply is coming directly from the Battery connectors The EGSM900 output is controlled by the power control loop From the EGSM900 output of the PA the RF signal is fed through the di...

Page 85: ...a diplexer for the RX and TX signals Moreover it sup presses the TX harmonics generated by the PA The antenna switch is controlled by the Mjoelner RF ASIC using the control signals CONT1 CONT2 and CONT3 The following table shows the possible different states Figure 2 Antenna Switch Test Points CONT1 Volt CONT2 Volt CONT3 Volt EGSM Rx DCS Rx PCS Rx EGSM Tx DCS PCS Tx 0 0 0 X 0 0 0 X 0 0 2 7 X 0 2 7...

Page 86: ...power level may be increased using Phoenix if it makes the Tx pulse easier to see Relevant components have been visually inspected for orientation placement etc The transmit signal has been checked with a spectrum analyzer at RF connector X602 and was found to be too low or non existent The VCO is running correctly Antenna Switch Control Line During EGSM Transmission Transmit Timing TXIOUTP TXC VT...

Page 87: ... existent The VCO is running correctly The Power Amplifier is getting a correct VBATRF supply via L805 L809 Mjoelner s supply voltages VR1A VR2 VR3 VR4 VR5 VR7 are all working cor rectly START Is EGSM TXIN signal at R805 OK Check Z701 Biasing components NO Is Signal at C733 OK Is signal at L807 OK YES Are TX I Q on C715 C716 OK Are digital I Q signals OK on J123 J214 Change Mjoelner Are TXP TXC vi...

Page 88: ...e LO signal corresponding to the wanted TX channel The GSM1800 GSM1900 TX output of Mjoelner is a balanced signal From the output of Mjoelner the signal is fed through the Balun T701 Balanced to single ended and an 3 dB pad to the PA GSM1800 1900 input The path of the PA The GSM1800 GSM1900 part of the PA has a maximum output of app 33dBm The sup ply is coming directly from the Battery connectors ...

Page 89: ...trol loop Mjoelner is receiving the Reference TXC from Baseband and not getting any feedback CONT1 Volt CONT2 Volt CONT3 Volt EGSM Rx DCS Rx PCS Rx EGSM Tx DCS PCS Tx 0 0 0 X 0 0 0 X 0 0 2 7 X 0 2 7 0 X 2 7 0 0 X START Is TX Signal at DCS PCS In on R819 OK Is signal on C823 OK Is VPD_1800 signal OK Replace PA Investigate Mjoelner Is signal at DCS PCS Input of Z601 OK Replace L801 Are Z601 Control ...

Page 90: ... input on R706 This case is the same for EGSM DCS1800 DCS1900 NEM 4 Synthesizer There is only one PLL synthesizer generating frequencies for both Rx and Tx for all three bands EGSM900 GSM1800 and GSM1900 VCO frequency is divided by 2 or by 4 in Mjoelner depending on which band is active General instructions for Synthesizer Troubleshooting Connect the phone to a PC with DAU 9P cable and dongle and ...

Page 91: ...ile Alt F Scan Product P Wait until phone information shows in the lower right corner of the screen Set operating mode to local mode Start RF Control window Select Testing Alt S RF Controls R Wait until the RF Controls window pops up Set the synthesizer to the following mode Select Band GSM 900 Active unit RX Operation mode Continuous RX TX Channel 37 The setup should now look like this ...

Page 92: ...easure frequency of 3769 6MHz at the output of the VCO G701 using a resistive probe and a spectrum ana lyzer It is possible to measure tuning voltage at charge pump output C710 easily For fVCO 3769 6MHz the tuning voltage should be 2 3VDC 2 8VDC Tuning sensitivity of VCO is 240MHz V typ Figure 3 PLL Synthesizer Test Points If this is not the case then go to Fault finding chart in this document for...

Page 93: ...CCS Technical Documentation RF Troubleshooting Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 b 89 Company Confidential Figure 4 Mjoelner Can Test Points ...

Page 94: ...egister of Mjoelner and an additional bit in the RefOSCCntl register of the Mjoelner That is necessary for the rough calibration of the VCXO The VCXO is fine tuned by programming the AFC value via the serial bus of Mjoelner The necessary AFC value is written into the RefOSCAFC register in Mjoelner VCO The VCO is able to generate frequencies in the range from 3420MHz to 3980MHz when PLL is in funct...

Page 95: ...7 Check VCO Out Is LO visible PLL is working Check VR7 J618 Vge OK Check VR7 VCO Side of R730 Vge OK Change R731 Refer to BB Fault Finding Does the VC Vge change when you change channels Check T702 Balanced O P Signal same Check T702 I P LO Present Change T702 Change R730 Test with Spectrum Analyzer Test with Oscilloscope Replace Mjoelner Replace G701 Check Mjoelner Voltage Supplies VR1A VIO VR3 V...

Page 96: ...cation Rpa Ref filter 3 RFBUSX RFBUSDA RFBUSCLK Synth supply filter Ref clk set VR5 VR3 RFCONV_0 9 VIO V C O S E N S E VR2 VIO SELADDR GENIO6 VCXO supply filter VR7 LPR CLK buffer VCO supply filter VR1A 5V 64 65 NDIV ADIV ϕ Charge Pump RDIV 1 2 1 4 1 2 1 4 1 2 Buffer LOCNT REFCNT Lock Detect Digital Control Main Bias Circuit Resistor Ext R2H R2 VDDRXBB Sensor BIST Temp V D D T X I O level shift Bu...

Page 98: ...NEM 4 Company Confidential RF Troubleshooting CCS Technical Documentation Page 6 b 94 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential Loop Filter VCO and power supply ...

Page 100: ...9 907 8 952 8 3631 2 3811 2 1002 885 6 930 6 3542 4 3722 4 28 895 6 940 6 3582 4 3762 4 90 908 0 953 0 3632 0 3812 0 1003 885 8 930 8 3543 2 3723 2 29 895 8 940 8 3583 2 3763 2 91 908 2 953 2 3632 8 3812 8 1004 886 0 931 0 3544 0 3724 0 30 896 0 941 0 3584 0 3764 0 92 908 4 953 4 3633 6 3813 6 1005 886 2 931 2 3544 8 3724 8 31 896 2 941 2 3584 8 3764 8 93 908 6 953 6 3634 4 3814 4 1006 886 4 931 4...

Page 101: ... 8 557 1719 2 1814 2 3438 4 3628 4 651 1738 0 1833 0 3476 0 3666 0 745 1756 8 1851 8 3513 6 3703 6 839 1775 6 1870 6 3551 2 3741 2 558 1719 4 1814 4 3438 8 3628 8 652 1738 2 1833 2 3476 4 3666 4 746 1757 0 1852 0 3514 0 3704 0 840 1775 8 1870 8 3551 6 3741 6 559 1719 6 1814 6 3449 2 3629 2 653 1738 4 1833 4 3476 8 3666 8 747 1757 2 1852 2 3514 4 3704 4 841 1776 0 1871 0 3552 0 3742 0 560 1719 8 18...

Page 102: ... 8 647 1877 2 1957 2 3754 4 3914 4 741 1896 0 1976 0 3792 0 3952 0 554 1858 6 1938 6 3717 2 3877 2 648 1877 4 1957 4 3754 8 3914 8 742 1896 2 1976 2 3792 4 3952 4 555 1858 8 1938 8 3717 6 3877 6 649 1877 6 1957 6 3755 2 3915 2 743 1896 4 1976 4 3792 8 3952 8 556 1859 0 1939 0 3718 0 3878 0 650 1877 8 1957 8 3755 6 3915 6 744 1896 6 1976 6 3793 2 3953 2 557 1859 2 1939 2 3718 4 3878 4 651 1878 0 19...

Page 103: ... TX part will require TX Power Level Tuning and TX IQ Tuning In general repairs in the RX part or PLL part always require RX Calibration Rx Band Filter Response Calibration If Mjoelner is changed all calibrations have to be done Other parts interfacing to TX RX or PLL might require tuning but common sense should be used e g if a component that has no influence on RF performance has been changed e ...

Page 104: ...XO calibration The VCXO calibration ensures the function of an initial synchronization before location update is done when the mobile station is in Normal mode For an error free initial syn chronization the 26MHz frequency of the VCXO must be accurate enough Therefore a VCXO cal value is written into the RefOSCCAL register of the Mjoelner During VCXO calibration the VCXO cal value is changed by a ...

Page 105: ... Nokia Corporation Page 6 b 101 Company Confidential The setup should now look like this Press Start and a window pops up Connect an external signal generator to the RF connector of the phone and set the gen erator as told in the window taking care for external cable losses Press ok and the window closes ...

Page 106: ...chnical Documentation Page 6 b 102 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential A typical result will look like this Press Save and Continue RX Calibration for EGSM is finished and the tuning continues automatically with GSM1800 ...

Page 107: ...2003 Copyright 2003 Nokia Corporation Page 6 b 103 Company Confidential GSM1800 DCS PCN Set the generator as instructed and press OK A typical result will look like this Press Save and Continue RX Calibration for GSM1800 is finished and the tuning contin ues automatically with GSM 1900 ...

Page 108: ...e generator as instructed and press OK A typical result will look like this Press Save and Continue RX Calibration is finished and the tuning is fully completed RX AGC limits The Rx calibration is only valid if it is within certain limits For the most recent limits see NEM 4 Production Testing Requirements If calibration is not within limits there is a fault in the RX chain ...

Page 109: ...2003 Copyright 2003 Nokia Corporation Page 6 b 105 Company Confidential Below the values for RSSI4 and RSSI7 are given RSSI4 Rx A5 RSSI7 Rx A8 band min typ max EGSM900 81 86 91 GSM1800 79 84 89 GSM1900 79 85 89 band min typ max EGSM900 103 108 113 GSM1800 99 105 109 GSM1900 100 104 110 ...

Page 110: ...NEM 4 Company Confidential RF Troubleshooting CCS Technical Documentation Page 6 b 106 Copyright 2003 Nokia Corporation Issue 1 09 2003 Company Confidential This page intentionally left blank ...

Page 111: ...ilter Response Compensation needs to be done on all three bands The proce dure begins with EGSM and continues automatically with GSM1800 and GSM1900 Set operating mode to local mode Select Testing Alt S RF Controls V Wait until the RF Controls window pops up Select Band GSM 900 Select Tuning Alt u RX Band Filter Response Compensation B Select Input Signal Level 60dBm The setup should now look like...

Page 112: ...pops up Connect an external signal generator to the RF connector of the phone and set the gen erator as told in the window Press OK and a new window pops up Set the generator as told in the window Press OK and a new window pops up Repeat this sequence 9 times until all channels have been tuned Press Save and Continue RX Band Filter Response Compensation for EGSM is finished and the tuning continue...

Page 113: ...erator as instructed and press OK Repeat this sequence 9 times until all channels have been tuned Press Save and Continue RX Band Filter Response Compensation for GSM1800 is fin ished and the tuning continues automatically with GSM1900 GSM1900 PCS Band Filter Response Compensation has to be done first for EGSM and GSM1800 bands see previous chapters After the other bands have been tuned the tuning...

Page 114: ...Band Filter Calibration can be performed by clicking on Auto Tuning This requires a signal Generator that can be programmed to sweep a user defined list of frequencies EGSM900 Select Automatic Tuning mode Press start and then Tune A window pops up Connect an external signal generator to the RF connector of the phone and let the signal generator step sweep through the programmed frequency list Pres...

Page 115: ... Compensation has to be done first for EGSM band see previous chapter After tuning the EGSM band the tuning continues automatically with GSM1800 and the following window should be seen Set the generator to sweep the frequency list as instructed and press OK Press Save and Continue RX Band Filter Response Compensation for GSM1800 is fin ished and the tuning continues automatically with GSM1900 ...

Page 116: ...ollowing window should be seen Set the generator to sweep the frequency list as instructed and press OK Press Save and Continue RX Band Filter Response Compensation for all three bands is finished and the tuning is fully completed RX Channel Select Filter Calibration This calibration is calibrating the Base band filter inside Mjoelner It is done by internally measuring a prototype filter for this ...

Page 117: ... Company Confidential NEM 4 Issue 1 09 2003 Copyright 2003 Nokia Corporation Page 6 b 113 Company Confidential The setup should now look like this Press Tune Press Stop Channel select filter calibration is finished and the tuning is fully completed ...

Page 118: ...able attenuator The use of a spectrum analyser or the power meter in GSM testers is likely to cause larger error than the use of a dedicated power meter and might cause the phone to be non compliant with GSM specifications Connect a calibrated powermeter to the RF connector of the phone Set operating mode of the phone to Local Select Tuning Alt U TX Power Level Tuning L Wait until the TX Power Lev...

Page 119: ...TX Data Type Random and TX PA Mode Low Tune the power levels except levels 5 and 6 according to the previous table by adjusting the corresponding coefficient values Press Save and Continue in order to continue with the next band GSM1800 DCS PCN Change the center frequency of the Spectrum Analyzer in the Spectrum Analyzer Set tings window as instructed and press OK From the main toolbar select TX D...

Page 120: ... uct specific Table 3 Press Save and Continue to finish TX Power Level Tuning TX I Q Tuning This tuning must be done in all three bands Caution In case you use a spectrum analyser make sure that the external attenuation 20 30dB between phone and spectrum analyser is high enough that the input of the analy ser can t be destroyed Adjust the reference level offset according to the insertion loss from...

Page 121: ...ontinues automatically to GSM1800 PCS PCN and GSM1900 PCS EGSM900 EGSM If a spectrum analyzer is used then use the following settings The following default values of the main toolbar should be used Table 4 EGSM EGSM900 Center Frequency 897 4 MHz Frequency Span 200 300 kHz Resolution Bandwidth 3kHz Video Bandwidth 3kHz Sweep Time 3 sec Sweep Type Clear Write Detector Type Max Peak Reference level 3...

Page 122: ...ws now a plot like this The purpose of this tuning is to tune the carrier signal and the 67kHz signal to a mini mum level Marker 2 and 3 Use the variables TX I DC offset and TX Q DC offset to adjust the carrier signal to a minimum level Marker 2 Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 897 4 MHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 1...

Page 123: ...ght 2003 Nokia Corporation Page 6 b 119 Company Confidential After tuning to the minimum the level difference between the peak levels at marker 1 and 2 must exceed 40dB Tuning is possible by using arrow keys on the keyboard Pushing the sliders by using the mouse is less sensitive but even possible ...

Page 124: ... the level difference between the peak levels at marker 1 and 3 must exceed 40dB Tuning is possible by using arrow keys on the keyboard Pushing the sliders by using the mouse is less sensitive but even possible Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 897 4 MHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 10 0 10 20 30 65 35 1 2 3 Marker 1 T...

Page 125: ... the next band Note The optimal values for I and Q Offset and Amplitude and Phase Difference vary from phone to phone Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 897 4 MHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 10 0 10 20 30 65 35 1 2 3 Marker 1 T1 33 40 dBm 897 33229000 MHz 1 T1 33 40 dBm 897 33229000 MHz 2 T1 20 35 dBm 897 40000000 MHz ...

Page 126: ...s of the main tool bar should be used Band GSM 1800 Active Unit TX Operation Mode Burst RX TX Channel 700 TX PA Mode Free TX Data Type All1 Select TX Power Level 0 from the RF Controls window Table 5 GSM1800 Center Frequency 1747 8MHz Frequency Span 200 300 kHz Resolution Bandwidth 3 kHz Video Bandwidth 3 kHz Sweep Time 3 sec Sweep Type Clear Write Detector Type Max Peak Reference level 35 dBm Mar...

Page 127: ...gnal to a minimum level Marker 2 After tuning to the minimum the level difference between the peak levels at marker 1 and 2 must exceed 40dB Tuning is possible by using arrow keys on the keyboard Pushing the sliders by using the mouse is less sensitive but possible Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 1 7478 GHz Span 300 kHz 27 5 dB Offset A 1MA Unit...

Page 128: ...imum the level difference between the peak levels at marker 1 and 3 must exceed 40dB Tuning is possible by using arrow keys on the keyboard Pushing the sliders by using the mouse is less sensitive but even possible Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 1 7478 GHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 10 0 10 20 30 65 35 1 2 3 Marke...

Page 129: ...ith the next band Note The optimal values for I and Q Offset and Amplitude and Phase Difference vary from phone to phone Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 1 7478 GHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 10 0 10 20 30 65 35 1 2 3 Marker 3 T1 28 50 dBm 1 74786771 GHz 3 T1 28 50 dBm 1 74786771 GHz 1 T1 23 48 dBm 1 74773229 GHz 2 ...

Page 130: ...s of the main tool bar should be used Band GSM 1900 Active Unit TX Operation Mode Burst RX TX Channel 661 TX PA Mode Free TX Data Type All1 Select TX Power Level 0 from the RF Controls window Table 6 GSM1900 Center Frequency 1880MHz Frequency Span 200 300 kHz Resolution Bandwidth 3 kHz Video Bandwidth 3 kHz Sweep Time 3 sek Sweep Type Clear Write Detector Type Max Peak Reference level 35 dBm Marke...

Page 131: ...al to a minimum level Marker 2 After tuning to the minimum the level difference between the peak levels at marker 1 and 2 must exceed 40dB Tuning is possible by using arrow keys on the keyboard Pushing the sliders by using the mouse is less sensitive but even possible Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 1 88 GHz Span 300 kHz 27 5 dB Offset A 1MA Uni...

Page 132: ...nimum the level difference between the peak levels at marker 1 and 3 must exceed 40dB Tuning is possible by using arrow keys on the keyboard Pushing the sliders by using the mouse is less sensitive but even possible Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 1 88 GHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 10 0 10 20 30 65 35 1 2 3 Marker...

Page 133: ...e TX IQ tuning Note The optimal values for I and Q Offset Amplitude and Phase Difference vary from phone to phone Ref Lvl 35 dBm Ref Lvl 35 dBm RBW 3 kHz VBW 3 kHz SWT 3 s RF Att 30 dB 30 kHz Center 1 88 GHz Span 300 kHz 27 5 dB Offset A 1MA Unit dBm 60 50 40 30 20 10 0 10 20 30 65 35 1 2 3 Marker 3 T1 27 22 dBm 1 88006771 GHz 3 T1 27 22 dBm 1 88006771 GHz 1 T1 25 76 dBm 1 87993229 GHz 2 T1 27 30 ...

Page 134: ...F UPP_WD2 takes care of controlling the traffic on the bus If the interface is faulty from the UPP WD2 s end the phone won t boot properly as pow ering configurations don t work Traffic on the bus can be monitored from three pins on the LPRF module Pins 34 35 and 36 Figure 1 CBUS measuring points In the pictures below CBUS traffic at bootup is shown CbusEnx is connected to Ch1 Cbus Da to Ch2 and C...

Page 135: ...lash test pad pattern is 2 78V and on the UPP WD2 end it is 1 8V The functionality of this interface should not affect the device boot into NORMAL LOCAL nor TEST modes Phoenix tests can be performed through MBUS interface in the case of a failure in FBUS interface Flashing is not possible if there is a problem in FBUS MBUS MBUS is a two wire RX and TX interface between UPP and UEM From UEM the int...

Page 136: ...onfidential Bluetooth Troubleshooting diagrams Do you have any FPS 8 errors Does the phone s main SW flash correctly Attempt to re flash the phone Go to Calypso s Flashing Troubleshooting Section BT Failure Part I Flashing problems No Yes Yes No Does the BT SW flash correctly BT Flashing OK 1 Replace BT MCM 2 Attempt to Flash Phone Yes No NEM 4 ...

Page 137: ...go Pins electrically connected to BT antenna i e short circuit Replace BT antenna i e new chassis Can you make a connection to BT Box Go to BT Failure Part III Go to BT Failure Part III Is BER 0 1 BT OK No Yes Yes No Yes Yes No No Check soldering of BT MCM with microscope No Yes Re Flash phone using option BT ONLY Is BT MCM propely soldered to the PWB Replace BT MCM Is soldering so bad that you mu...

Page 138: ...Pin 6 with O scope Does Vin 300 900mVpp Does Freq 26MHz Check SYSCLCK Pin 50 with O scope Can you make a connection to BT Box Check VFLASH1 L431 Check VCTCXO Buffer Section Check VBAT L430 C431 BT Failure Part III BER Failure BT OK 1 Replace BT MCM 2 Flash Phone using BT ONLY Is BER 0 1 1 Replace BT MCM 2 Flash Phone using BT ONLY Yes Yes Yes No No Yes No No Yes Yes No Yes No Yes No No L431 2 9 L4...

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