CCS Technical Documentation NPM-2NX Series Transceivers Troubleshooting Issue 1 07/02 ãNokia Corporation
NPM-2NX Troubleshooting CCS Technical Documentation Contents Page No Transceiver Troubleshooting ......................................................................................... 4 General about testing ...................................................................................................4 Phone operating modes ............................................................................................. 4 Measurement points ............................................................
NPM-2NX Troubleshooting CCS Technical Documentation Fault finding chart for 19.2 MHz oscillator ............................................................ 55 RX VHF VCO ...........................................................................................................55 Fault finding chart for RX VHF VCO .................................................................... 55 BB PLL ...................................................................................................................
NPM-2NX Troubleshooting CCS Technical Documentation Transceiver Troubleshooting General about testing Phone operating modes Phone has three different modes for testing/repairing phone. Modes can be selected with suitable resistors connected to BSI- and BTEMP- lines as following: Table 1: Mode selection resistors Mode BSI- resistor BTEMP- resistor Normal 68k 47k Local 560_ (<1k_) What ever Test 3.3k (> 1k) 560_ (<1k_) Remarks Recommended with baseband testing.
NPM-2NX Troubleshooting CCS Technical Documentation Measurement points Figure 1: UEM regulator's filter capacitors VR1B VR1A VCORE VFLASH VFLASH VANA VR6 VR4 VR2 UEM VR7 VR3 VR5 VSIM VIO Issue 1 07/02 ãNokia Corporation Page 5
NPM-2NX Troubleshooting CCS Technical Documentation Figure 2: BB testpoints FLASH Page 6 CbusDA CbusENX CbusCLK Fbus TX DbusENX FbusRX MbusTX MbusRX SLEEPCLK UEMINT SLEEPX PURX DbusCLK DbusDA UEM RFCLK: Init clk 19.
NPM-2NX Troubleshooting CCS Technical Documentation Baseband Troubleshooting Note: ESN and IMEI has to re-written to phone If UEM is replaced. This can be done only in Central Service.
NPM-2NX Troubleshooting CCS Technical Documentation •Hw "core" regulators "on": Vio, Vcore, VR3, Vflash1 •These regulators are supplying the processors, memory, chip interfaces and clock source in RF • Reset releasing delay •Supply voltages stabilize to their UEM hw default values •RFCLK grows to full swing •Core is ready to run but waiting for PURX release • Reset releasing •UPP releases the SLEEPX up to "non sleep" -state to prevent the UEM switching the regulators "OFF" MCU starts running the Boots
NPM-2NX Troubleshooting CCS Technical Documentation Figure 3: Power up sequence 1 Power key pressed • After 20ms UEM enters RESET MODE if VBAT>Vmstr+ 2 2) VFLASH1, Vana, Vcore, Vio and VR3 goes high. • VCTCXO enabled by VR3 -> RFClk 19.2 MHz running. 3 Purx released • Purx released by UEM, UEMINT goes high for 100 ms and about 500ms RFCLK will change 13MHz (GSM mode), SleepX goes high and UEM starts feeding SleepClk (32 KHz) to UPP.
NPM-2NX Troubleshooting CCS Technical Documentation Phone does not start up normally or does not stay on Note! In case of power up faults, it's not possible to force phone on by disabling watchdog. Instead, measurements should be done immediately when power key pressed or when battery voltage connected to phone (local/test mode). The easist way to check if software is running when phone takes abnormal amount of current is to measure cbusclk and Vcore. Dbus clock (programmable 9.
NPM-2NX Troubleshooting CCS Technical Documentation Figure 4: Fault tree, phone does not power up Try to start phone to test or local mode Check the power key OK OK FAIL Measure Vflash1,Vana,Vio,Vcore ,VR3 when pwr key pressed OK Check R202, R203, R205, C217, C220 OK FAIL Check X101,C108, C109,Z101 VR3 missing Check G801 (missing, misaligned) FAIL Measure VBAT from C262 Check 13MHz /GSM or 19.44/TDMA RF-clock from C420 FAIL Check C420 OK OK OK Check that purx goes up to 1.
NPM-2NX Troubleshooting CCS Technical Documentation •FBUSTX(serial data to phone), •FBUSRX(serial data from phone), •MBUS(serial clock for FBUSRX) •VPP(External flashing voltage for speed up flashing) • Also BSI line is used when initializing flashing(battery connector) • When phone is powered(VBAT>3V ) MBUS and FBUSTX lines are pulled up internally by phone. • Prommer sends command to UEM, using FBUSRX, to enter Flash-mode.
NPM-2NX Troubleshooting CCS Technical Documentation Flash programming error codes Error codes can be seen from "FPS-8 Flash" in Phoenix. Underlined note means that item under consideration is being used first time in flashing sequence. Table 2: Flash programming error codes Error Description Not working properly C101 "The Phone does not set FbusTx line high after the startup." Vbatt Vflash1 Vcore VIO BSI and FbusRX from prommer to UEM.
NPM-2NX Troubleshooting CCS Technical Documentation C384 C584 C684 "The Phone has generated NAK signal during data block transfer." (C384-during algorithm download to target phone) (C584-during erasing) (C684-during programming) Flash UPP Signals between UPP-Flash C585 C685 Data block handling timeout" (C585-during erasing) (C685-during programming) Flash UPP Signals between UPP-Flash C586 C686 "The status response from the Phone informs about fail.
NPM-2NX Troubleshooting CCS Technical Documentation Charging Note: Charging voltage and current can be checked by connecting phone to service software and reading ad- converter values of vchar and ichar.
NPM-2NX Troubleshooting Page 16 CCS Technical Documentation 3 In case of internal microphone/XEAR fail: Feed tone to microphone and measure signal from XEAR line. Audio test box JBA-8 is needed. Audio loop (Audio test/Hp In Ext Out) must be switched on by Phoenix service software. This loop will connect audios only through UEM. In this case UPP is not used. 4 Run audio- loop selftest with Phoenix (BB Self tests/ST_EAR_DATA_LOOP_TEST). This loop will test the eardata/micdata lines between UPP and UEM.
NPM-2NX Troubleshooting CCS Technical Documentation Earpiece or external microphone line does not work Figure 6: Fault tree, earpiece fail Earpiece doesn't work Run audio-loop selftest with phoenix OK Fail Feed 1KHz to Xmic by JBA-8 and measure from earpiece OK Fail Check R157,L152, L158,C150,C164, C153, C165,R152, C156,C155,R164, R161,R153,R150, C159,C167,V153 OK Check earpiece Change UPP OK Change UEM Issue 1 07/02 ãNokia Corporation Page 17
NPM-2NX Troubleshooting CCS Technical Documentation .
NPM-2NX Troubleshooting CCS Technical Documentation Accessory detection • - Start phone to normal mode when checking accessory detection. • - Ad- converter value of headint and hookint - lines can be checked with Phoenix ADC-reading. • - When headset HDC-9 connected and headset push button is held down, headint- value should be between 10 and 50 and hookint- value between 0-30.
NPM-2NX Troubleshooting CCS Technical Documentation Power supply for data cable DLR-3 needs power supply for data transfering. SGND will supply 2.8V to DLR-3. - Start phone to normal mode when checking DLR-3 detection Figure 9: Fault tree, data cable. DLR-3 data cable doesn't work Connect DLR-3, check DLR-3 detection Fail Check the components of XMIC, HEADINT and MICB2 lines Ok Check bottom connector Ok Check VFlash2 (~2.8V) Fail OK Check SGND voltage from Ok bottom connector (2.40-2.
NPM-2NX Troubleshooting CCS Technical Documentation • Phone clock (on display) does not function properly Figure 10: Fault tree, sleep clock Sleep mode not working Measure sleep clock from J404 Fail Measure sleep clock from B200 Fail Check C203 &C204 Ok Ok Ok Change UPP (D400) Change UEM (D200) Change B200 Issue 1 07/02 ãNokia Corporation Page 21
NPM-2NX Troubleshooting CCS Technical Documentation Display/Keyboard lights do not work Figure 11: Fault tree, Display/Keyboard lights Display/Keyboard lights are not working Check R300 (Display) and R301 (Keyboard) FAIL Replace resistor(s) FAIL Replace LED(s) FAIL Replace UEM OK Check LEDs V300...V303,V310-V311 (Display) and V304...
NPM-2NX Troubleshooting CCS Technical Documentation Display does not work Figure 12: Fault tree, display Display does not work Check that phone powers up norm ally (current consumption, power up sequence) In any phase of display troubleshooting use Display Test in Phoenix to produce test patterns on display. FAIL Proceed to phone doesn't power up troubleshooting Also check with a known good display module to see if it works.
NPM-2NX Troubleshooting CCS Technical Documentation No sound: Try using known good buzzer instead. If still no sound ->change UEM(D200) Weak sound: Use Audio test in Phoenix to set buzzer parameters(frequency, strength). If it doesn't effect to the sound level ->change buzzer. Vibra does not work Check spring connectors and C307. No vibration: Try using known good vibra instead.
NPM-2NX Troubleshooting CCS Technical Documentation Infrared does not work Figure 13: Fault tree, infra red Infra Red not working Measure Vflash1 from IR module VCC(pin6), should be 2.78V FAIL Change UEM(D200) FAIL Replace faulty component(s) OK Check R350, R351, C351 and V350 OK Use ST_IR_LOOP_TEST(in BB Self Tests) in Phoenix OK FAIL Measure Tx Data from IR module(pin3) 2.78V, 9.6/115.
NPM-2NX Troubleshooting CCS Technical Documentation RF Troubleshooting Introduction Measurements should be done using spectrum analyzer and high-frequency probe (Local and reference frequencies and RF-power levels in intermediate stages of chain). Oscilloscope is used to measure DC-voltages and low frequency signals. Multimeter is also useful measurement equipment in faultfinding. Also cellular tester is needed in order to perform tests mentioned in this document.
NPM-2NX Troubleshooting CCS Technical Documentation PWRDET PLL RF RX T: TX U/C UHF V: VCO VHF AF: Power detector module Phase Locked Loop Radio Frequency Receiver Time between pulses Transmitter Up converter (mixer and driver in same package) Ultra High Frequency Voltage of signal (measured with oscilloscope) Voltage controlled oscillator Very High Frequency Audio Frequency Receiver General instructions for RX troubleshooting Receiver troubleshooting is divided into three sections: - General checking - L
NPM-2NX Troubleshooting CCS Technical Documentation Path of the received signal Block level description of the receiver: Diplex filter 850 / 1900 1930 ... 1990 MHz 869 ... 894 MHz Duplex filter 1900 MHz Duplex filter 850 MHz LNA LNA 1900 850 Band filter Band filter st st 1 mixer 133.2 MHz kHz BW200 1 mixer 134.04 MHz BW30 kHz GSM ch filter AGC TDMA SAFARI GTE AGC 25/20 dB 1 step 2063 ... 2124 MHz UHF LO 1003...1029MHz (VCO / 2) ch filter AGC AGC 1...31 dB, 5 steps 133.
NPM-2NX Troubleshooting CCS Technical Documentation AMPS Fault finding chart Apply signal to ext. antenna connector f= 881.4 MHz ch 380) mod.= 1004 dev.= 8 kHz level= -116dBm Connect audio box from the bottom connector to audio Analyzer SINAD > 12 dB AMPS RX is OK SINAD < 12 dB Apply signal to ext. antenna connector f=881.
NPM-2NX Troubleshooting CCS Technical Documentation Step 1. General checking Check signal level at RX band filter Z801 input Not OK Check VR4 supply and components if these ok => replace Safari N801 OK Not OK Check signal level at mix1_A input, L809 OK Check signal level at IF filter Z803 input (134.04 MHz), R801 Not OK OK Replace RX band filter Z801 Measure VR4 from L812 and L811pads OK Not OK OK Check components L812, Replace Safari N801 L811 etc.
NPM-2NX Troubleshooting CCS Technical Documentation Audio test Please use Phoenix RF-control to set phone to the correct operating mode. Enable audio using Phoenix software (maintenance -> testing -> audio test mode -> set audio test mode). See picture below. Step 2. Local oscillator checking Carrying out this step VCO signal of 1st and 2nd mixers can be checked. 2nd mixer RX VHF VCO frequency is constant 268.08 MHz but for the 1st mixer UHF VCO frequency depends on the channel.
NPM-2NX Troubleshooting CCS Technical Documentation 2) Set phone to TDMA mode and select RF Test UI in Phoenix (Maintenance => Testing => RF Test). 3) Make sure that signal generator allows phone TX power going to its output. Use low power level, for example 10. Set channel to 380 and select "Write Init". 4) Set spectrum analyzer settings as following: - Center frequency: 268.
NPM-2NX Troubleshooting CCS Technical Documentation power level, for example 10. Set channel to 380 and press "Write Init". 4) Connect oscilloscope probe to one of the RX I/Q test points on PWB (all four testpoints J808, J809, J818 and J819 are located behind display) 5) Check that there is a clean signal in each test points. 6) Decrease signal level slowly down to -115 dBm and make sure that AGC keeps signal in visible (This can be noticed by looking at the RX I/Q voltage during signal level change).
NPM-2NX Troubleshooting CCS Technical Documentation Fault finding chart A pply signal to ext. antenna connector f= 1960.
NPM-2NX Troubleshooting CCS Technical Documentation Check signal level at RX band filter Z802 input Not OK Check components around lna and measure supply voltages OK Check signal level at mix1_B input, L810 Not OK Replace RX band filter Z802 OK Continue troubleshooting as in AMPS/TDMA800 Step 1. Local oscillator checking Carrying out this step VCO signal of 1st and 2nd mixers can be checked. 2nd mixer RX VHF VCO frequency is constant 268.
NPM-2NX Troubleshooting CCS Technical Documentation => RF Test). 3) Set channel to 1000 and press "Write Init". 4) Set spectrum analyzer settings as following: - Center frequency: 268.08 MHz, Span: 200 kHz - RBW: 3 kHz, reference level: 0 dBm 5) Connect spectrum analyzer probe on the inductor L818 and record RX VHF VCO signal level and frequency. Signal level should be around -25 dBm and frequency 268.08 MHz. 6) Set spectrum analyzer settings as following: - Center frequency: 2094.
NPM-2NX Troubleshooting CCS Technical Documentation Apply signal to ext. antenna connector f= 1960.06771 (ch 661) unmodulate level= -83dBm Check signal level at RX I/Q J808, J809, J818, J819 STEP 3. Not OK OK GSM1900 RX is OK According STEP 4.
NPM-2NX Troubleshooting CCS Technical Documentation Check signal level at RX band filter Z802 input Not OK Check components around lna and measure supply voltages Not OK Replace RX band filter Z802 OK Check signal level at mix1_B input, L810 OK Check signal level Not OK at IF filter Z804 input (133.2 MHz, R803) OK Measure VR4 from L815 OK and L814 pads Not OK Start synthesizer troubleshooting OK Check components L815, Replace Safari N801 L814 etc.
NPM-2NX Troubleshooting CCS Technical Documentation If the cable losses are calibrated correctly the RSSI reading should give reasonable result (-80 dBm +/- 2 dB). Please note that RSSI result is valid only if there has not been RX calibration attempts for the faulty phone. If the RSSI level is several dB's lower go to Step 2 (Local oscillator checking). Step 2. Local oscillator checking Carrying out this step VCO signal of 1st and 2nd mixers can be checked. 2nd mixer RX VHF VCO frequency is constant 266.
NPM-2NX Troubleshooting CCS Technical Documentation level and frequency. The result should be like in the picture below: 2) Set spectrum analyzer settings as following: - Center frequency: 266.4 MHz, Span: 200 kHz - RBW: 3 kHz, reference level: 0 dBm 3) Connect spectrum analyzer probe on the inductor L818 and record RX VHF VCO signal level and frequency. The result should be like in the picture below: 4) Set Rx/Tx channel to 661 using Phoenix.
NPM-2NX Troubleshooting CCS Technical Documentation - RBW: 3 kHz, reference level: 10 dBm 6) Connect spectrum analyzer probe to testpoint J813 and record UHF VCO signal level and frequency. The result should be like in the picture below: 7) Repeat measurement for channels 512 and 810. Step 3. RX chain checking 1) Set signal generator frequency to 1960.06771 MHz and level to -83 dBm. 2) Set phone receiver to continuous mode with full gain using Phoenix.
NPM-2NX Troubleshooting CCS Technical Documentation 3) Connect oscilloscope probe to one of the RX I/Q test points on PWB (all four testpoints J808, J809, J818 and J819 are located behind display) 4) Measure frequency and peak-to-peak voltage of RX I/Q signal from each test points. Signal should look like in the picture below: - If only one or two testpoints shows correct signal and rest of the testpoints are either deaf or signal is very small, the fault is probably due to Safari ASIC.
NPM-2NX Troubleshooting CCS Technical Documentation - Center frequency: 133.2 MHz, Span: 200 kHz - RBW: 3 kHz, reference level: -20 dBm 3) Set phone receiver to continuous mode with the following gain settings using Phoenix (see picture of controls in step 3). 4) Connect spectrum analyzer probe to the output of GSM IF filter (at the one end of R804) and record the level. 5) Connect spectrum analyzer probe to the input of GSM IF filter (at the one end of R803) and record the level.
NPM-2NX Troubleshooting CCS Technical Documentation Transmitter General instructions for TX troubleshooting Always use an RF-cable connected from an external RF-connector to analyzer via (rfpower) attenuator. This is important to protect analyzer against excessive RF-power and not allow leakage of undesired RF-power into RF-power into cellular frequencies. AMPS/TDMA Start Phoenix-software and select TX mode under testing (AMPS, DAMPS or TDMA1900).
NPM-2NX Troubleshooting CCS Technical Documentation guide. 1900 UHF-PLL 2G (÷2) (2063.4-2124 MHz, HB) (1003.08-1028.01 MHz,LB) 1900MHz D I P DIV 2 VHF-PLL 356.4 MHz 358.08 MHz VHF 426.4 MHz 428.16 MHz VCO 213.2 MHz 214.08 MHz 1900MHz I 800 D E T 800MHz Q 800MHz PA 178.2 MHz 179.04 MHz U/C Safari GTE Fault finding charts for transmitter AMPS Start Phoenix-software and set phone to the Analog mode. Set channel 383 and Power level 2.
NPM-2NX Troubleshooting Page 46 CCS Technical Documentation ãNokia Corporation Issue 1 07/02
NPM-2NX Troubleshooting CCS Technical Documentation AMPS, PL2, CH383 Visual check of TX block - PA and up converter -TX SAW - Duplex filter - Passive components OK Check LO-signal (1015.53MHz) @L979&L980 and TX VHF (358.08 MHz)@N811 NOK Start synth troubleshooting OK Check supply voltages: VR2,VBATTRF, VR5, IPA1,BANDSEL, TX_ENABLE TX_GAIN_CONTROL NOK Check UEM and UPP (Baseband) OK Check TXi/q signals Test points J810...J811 Check UEM (Baseband) NOK OK Check TX IF power (179.
NPM-2NX Troubleshooting CCS Technical Documentation NOK Check TX SAW input and output power IL: 3 dB Change TX SAW filter Z905 OK Is Itot 850 ... 1000 mA? Check PA output power and gain. Output power: ~28 dBm Gain: ~30 dB NOK Change PA N901 OK NOK Check PWRDET N900 insertion loss IL<0.3 dB Change PWRDET N900 OK Check duplexer Z906, diplexer Z908 and RF connector X900 Dupl IL: ~2.2 dB Dipl IL: ~0.35 dB RF conn: ~0.
NPM-2NX Troubleshooting CCS Technical Documentation TDMA1900: GSM1900: Issue 1 07/02 ãNokia Corporation Page 49
NPM-2NX Troubleshooting CCS Technical Documentation TDMA1900, PL2, CH1000 GSM1900, PL0, CH661 NOK Is TDMA800 mode OK? Start AMPS troubleshooting OK Check LO-signal NOK (TDMA 2094.06 GSM 2093.2MHz)@L979&L98 0 and TX VHF (TDMA 428.16 GSM 426.4 MHz)@N811 Start synth troubleshooting OK Check supply voltages: VR2,VBATTRF, VR6, IPA2,BANDSEL, TX_ENABLE TX_GAIN_CONTROL NOK Check UEM and UPP (Baseband) OK Check TX IF input power (TDMA 214.08 GSM 213.
NPM-2NX Troubleshooting CCS Technical Documentation Is Itot TDMA 350...500 GSM 200 ... 300 mA? NOK Check PA output power and gain. Gain: ~30 dB Pout: TDMA ~29 dBm GSM ~32 dBm Change PA N901 OK NOK Check PWRDET N900 insertion loss IL< 0.3 dB Change PWRDET N900 OK Check duplexer Z962 , diplexer Z908 and RF connector X900 insertion loss Dupl IL ~2.2 dB Dipl ~0.35 dB RF conn ~0.
NPM-2NX Troubleshooting CCS Technical Documentation own coupler. N Is TXPWRDET vs. output power OK? See chart below. Check VR2 and PATEMP . Check C921, C922 and PWRDET module. Note ! See TXPWRDET vs. Output power curve Y N Is DAC value vs. TXPWRDET (mV) OK? Check UEM (BaseBand) The detected voltages are illustrated in the following table and diagram. AMPS AND TDMA Table 3: Typical detected voltages at power levels PL2...
NPM-2NX Troubleshooting CCS Technical Documentation GSM1900 Table 4: Typical detected voltages at power levels PL0...PL15 850 1900 Pout TXPWRDET Pout TXPWRDET, U_value dBm dac dBm dac 0 29.5 660 1 28 556 2 26 436 3 24 343 4 22 364 5 20 203 6 18 158 7 16 118 8 14 91 9 12 66 10 10 50 11 8 35 12 6 27 13 4 18 14 2 13 15 0 9 PL mV mV Note: DAC VALUES MAY VARY ABOUT +/- 20% Note: TXPWRDET is difference between TX on burst and off burst.
NPM-2NX Troubleshooting CCS Technical Documentation Synthesizers There are five oscillators generating the needed frequencies for RF-section. 19.2 MHz reference oscillator, 2GHz UHF VCO, TX VHF cascade amplifier VCO both RX VHF VCO and BB VHF integrated in Safari. RX VHF frequency is 268.08 MHz in TDMA and 266.4 MHz in GSM and TX VHF has three fixed frequencies, 358.08 MHz for lowband and 426.4 MHz in GSM and 428.16 MHz in TDMA upper band.
NPM-2NX Troubleshooting CCS Technical Documentation Fault finding chart for 19.2 MHz oscillator 2 Change VCTCXO OK 2.No START HERE! Is VCTCXO oscillating? 19.2MHz 1.No OK! OK 1 Check voltage C867 2.78 V No OK Check resistor R816 RX VHF VCO The RX VHF VCO signal is used to generate receiver Intermediate frequency. RX VHF VCO has two fixed frequencies: TDMA 268.08 MHz, GSM 266.4 MHz. Operating frequency is locked in Phase locked Loop. RX VHF VCO output signal is fed to SAFARI.
NPM-2NX Troubleshooting CCS Technical Documentation 4 Change SAFARI No 3 Check loopifilter components: C848, R808, C847, R807, C846, R820, C870 check also R826 OK 3.No OK 1 START HERE Is oscillator locked to TDMA 268.08 or GSM 266.4 MHz 2.No Yes OK! OK 2 Check resonator components: V801, C845, C871, L818 and DC block C821 BB PLL The BB PLL generates RF clock to base band. It has two fixed frequencies 77.
NPM-2NX Troubleshooting CCS Technical Documentation TDMA mode and 78 MHz in GSM mode. Next picture shows BB PLL working. VCTCXO 19.2 MHz Divider 65 or 80 * Data Freq/Phase comparator Charge Pump Divider 324 or 325 Active part Loop Filter Varactor Resonator BB VCO Divider 4 or 6 RF-IC RFCLK to BB GSM 13 MHz TDMA 19.44 MHz *Data are related to vctcxo frequency and mode selections. Fault finding chart for BB PLL Measure oscillator frequency over L829 coil.
NPM-2NX Troubleshooting CCS Technical Documentation GSM-> BB PLL frequency 78 MHz 4 Change SAFARI OK No 3 Check loopfilter components: C878, R834, C881, R835, C882 OK 3.No 1 START HERE Is oscillator locked to TDMA 77.76 or GSM 78 MHz 2.No Yes OK! OK 2 Check resonator components: V805, C871, L829 and C893 TX VHF VCO The TX VHF VCO signal is used to generate transmitter Intermediate frequency. TX VHF VCO has three fixed frequencies 358.08 MHz for lower band and TDMA 428.16 MHz and GSM 426.
NPM-2NX Troubleshooting CCS Technical Documentation GSM1900, CH661 -> TX VHF frequency 426.4 MHz 4 Check components: 5 Change cascade amplifier N811 C853, C852, C851, R810, R809, R821 and C841, C873, L828 OK 6.No 5.No OK OK 4.No 3 Check resonator components: OK 3.No 1 START HERE Is oscillator locked to 358.08, 426.4 or 428.16 MHz Yes 6 Change SAFARI OK! V802, C850, L820, C874, C865 2.No OK 2 Check operating voltage: 4.
NPM-2NX Troubleshooting CCS Technical Documentation Fault finding chart for UHF SYNTHESIZER OK Change VCO G802 3. No 4. No START HERE! 2. No No OK Is frequency locked? 2006.16 - 2124 MHz Check loopfilter components and balun T801, C863, C862, C861, C860, R806, R815, R814, R813 Yes Is EVM OK? OK! YES No OK low band Yes 1. No 1 Check loopfilter components OK Check VCO operatig voltage: 2.
NPM-2NX Troubleshooting CCS Technical Documentation Description of NPM-2NX RF Auto-tune Tuning TDMA RF tunings TDMA RX tunings AFC tuning • Purpose of the tuning is to correct phone frequency error • If AFC tuning fails it might be due to: • Problems with lower band signal path, synthesizer etc. • If AFC DAC tuning value or step size is too low or high it might be due to faulty VCTCXO component.
NPM-2NX Troubleshooting CCS Technical Documentation • Tuning results are only visible after unsuccessful tuning with auto-tune procedure • This tuning has done simultanously with AFC-tuning If LP and AMP2 filter tuníngs fail it might be due to: • Problems with lower band signal path (synthetizer etc.
NPM-2NX Troubleshooting CCS Technical Documentation • Purpose of the tuning is to tune DC offset and phase offset so low as possible (test limit –40 dBc) If tuning fails there can be following problems: • UEM or Safari • Too low output power TX power levels and crossband (TxPwr) • Purpose of this tuning is to tune all power levels (PL2 – PL10) • TX crossband: •Low band: Purpose to tune ch991 and ch799 equals to mid (ch383) channel power •Upper band: Purpose to tune ch2 and ch1998 equals to mid (ch10
NPM-2NX Troubleshooting CCS Technical Documentation GSM RF tunings GSM RX tunings LP and AMP2 filters tunings • This is done using Safari internal loop. No external signal is needed If it fails there can be following problems: • Safari problem GSM AFC tuning • Purpose of the tuning is to correct phone frequency error If AFC tuníng fails it might be due to: Page 64 • Problems with upper band signal path (synthesizer etc.
NPM-2NX Troubleshooting CCS Technical Documentation GSM UB LNA GAIN AND RSSI OFFSET • UB GSM reference gain (around 74 dB), measured when lna is switched off • UB LNA gain step, measured when lna is switched on.
NPM-2NX Troubleshooting CCS Technical Documentation GSM TX tunings If some TX tuning fails, start always TX troubleshooting! TX IQ • Purpose of this tuning is tune DC offset and phase offset so low as possible •Typical values Amplitude: -45 to –55 dBc and Phase: –50 to – 60 dBc If tuning fails there can be following problems: • UEM or Safari • Too low output power TX Power levels • Purpose of this tuning is tune all power levels (PL0 – PL15) If tuning fails there can be following problems: • Broken
