Nokia Customer Care 6255/6255i/6256/6256i (RM-19) Mobile Terminal RF Description and Troubleshooting Issue 2 05/2005 Company Confidential ©2005 Nokia Corporation
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Contents Page Introduction ..................................................................................................................................................... 5 Mobile Terminal Components ..................................................................................................................... 6 Main PWB ........................................................................................
Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Rx VHF LO Troubleshooting ....................................................................................................................59 Tx UHF LO (N7000) Schematic ..............................................................................................................60 Tx UHF LO (N7000) Troubleshooting ....................................................................................................
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Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Introduction When troubleshooting the receiver, first check the RX_AGC PDM value. The AGC value should be close to the typical values in the tables. The RX AGC tries to keep a constant amplitude at the output of the receiver chain; if the AGC value indicates an AGC gain that is substantially higher than normal, the AGC is compensating for extra loss in another component.
255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Mobile Terminal Components The mobile terminal includes two PWB boards, the main PWB and the UI PWB. Main PWB Following are the components of the main PWB.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Cell duplexer Cell coupler PCS coupler PCS duplexer Synthesizer IC Headset jack Rx RF Cell filter Diplexer Antenna connector N7160: Rx front-end VCO Rx RF PCS filter PCS PA Rx IF AMPS filter Cell PA VCTCXO Cell Tx filter Rx IF CDMA filter PCS Tx filter N7100: Rx downconverter N7000: Tx Upconverter FM radio IC UEM D2800 processor Flash Bluetooth IC Tomahawk connector Figure 2: Main PWB component layout
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care UI (Secondary) PWB Following are the components of the UI PWB.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care GPS ceramic antenna GPS antenna matching circuitry GPS 16.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Preliminary RF Troubleshooting The following sections identify steps to troubleshoot some common RF issues. Mobile Terminal Cannot Make a Call Verify the following if the mobile terminal cannot make a call: 1. The mobile terminal is in Normal Mode (i.e., the mobile terminal is searching for a signal, net server is on). 2. The Preferred Roaming List (PRL) is loaded into the mobile terminal. 3.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Transmitter RF Troubleshooting Following are the main Tx RF components.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Transmitter Block Diagram Following is the block diagram for the Tx RF system.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Transmitter Schematics The following schematics are for general reference only. See the Schematics chapter for detailed versions.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care PCS duplexer PCS PA Diplexer Couplers Component changes based on PA manufacturer Power detector Cell PA Cell duplexer Figure 8: Transmitter schematic 2 Page 14 ©2005 Nokia Corporation Company Confidential Issue 2 05/2005
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Transmitter Troubleshooting Setup Use the following sets of procedures to troubleshoot the transmitter using Phoenix. Due to the compact layout of the mobile terminal, some of the major test points are not accessible without destroying the shield frames and the EL lamp.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care 5. Click the LOCAL button in the Phone State area to put the mobile terminal into Local Mode. Figure 9: Phone Control dialog box 6. Open the Troubleshooting menu, point to AMPS, and click AMPS Control. The AMPS Control dialog box appears. Figure 10: AMPS Control dialog box 7. Click the Tx Control tab. 8. In the Set Channel field, type 384. 9. In the Power Level field, type 5. 10.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care 11. Configure the spectrum analyzer using the following values: • Center Frequency = 836.52 MHz • Span = 100 MHz • Amplitude = 20 dBm • Attenuation = Auto • BW = Auto Table 1: RF PDM Values at Power Level 5 Description/Field Reference Value AGC1 -512 AGC2 -31 AGC3 -400 Rx IF AGC -234 AFC +176 Pout at RF connector +14dBm Current 400-500mA Figure 11: RF PDM dialog box for AMPS 12.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Cell Tx Setup Use the following procedures to prepare for Cell Tx troubleshooting using Phoenix. 1. Connect an RF test connector to a call box. 2. Connect the mobile terminal to the PC via a test jig. (The bottom connector is a USB port.) 3. Connect a power supply to the mobile terminal. 4. On the Phone Control dialog box, click the LOCAL button in the Phone State area to put the mobile terminal into Local Mode.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care The CDMA Control dialog box appears. Do NOT select this option Figure 13: CDMA Control dialog box for Cell Tx troubleshooting 9. Select the following values: • State = Rho ON • Band = Cell • Radio Configuration = Mode 1: IS-95 Voice Note: Do NOT select the Set default PDM values option 10. Click Execute. 11. Configure the spectrum analyzer using the following values: • Center Frequency = 836.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Figure 14: RF PDM Control dialog box for Cell band 12. Click Read Phone to update the values. PCS Setup Use the following procedures to prepare for PCS Tx troubleshooting using Phoenix. 1. Connect an RF test connector to a call box. 2. Connect the mobile terminal to the PC via a test jig. (The bottom connector is a USB port.) 3. Connect a power supply to the mobile terminal. 4.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care 7. Select the following values on the RF Main Mode dialog box: • Band = PCS (CDMA) • Channel = 600 • Mode = Rx/Tx 8. Click Set. Note: Be sure that the “RF Main Mode set successfully” message appears in the status bar. 9. Open the Troubleshooting menu, point to RF, and click CDMA Control. The CDMA Control dialog box appears. (See Figure 13 on page 19.) 10. Select the following values on the CDMA Control dialog box.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Figure 15: RF PDM Control dialog box for PCS band 14. Click Read Phone to update the values. Transmitter RF Troubleshooting Procedures After Phoenix is set up using either the AMPS, Cell, or PCS setup procedures, use the following steps to troubleshoot the transmitter. 1. Using a voltmeter, check to see that all VR2, VR6, and VR1B are on the transmit system. (See "Tx DC Test Points - Bottom Side" on page 25.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care 4. Use an AAS-10 RF probe to probe the Cell Tx output of the N7000. • If there is no RF or low RF, look for SMD everywhere around the N7000. • If the SMD is okay, replace the N7000. 5. Probe the PA input. • If the level is low, look for an SMD issue on the Tx filter or matching transformer (T7001 or T7002). • Reflow or replace the filter as necessary. 6. Probe the PA output.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Tx Output Spectrum Following is the correct output of the mobile terminal on a spectrum analyzer with 100MHz span. Note that if you are using the AAS-10 probe with the mobile terminal connected to the call box, the amplitude should be approximately -7dBm at the antenna test point on the top of the PWB. Figure 16: Correct output spectrum Following is an example of incorrect output.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Tx DC Test Points - Bottom Side Following are the Tx DC test points located on the bottom side of the main PWB.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 4 shows the values for the test points in Figure 18. Table 4: Tx DC Test Point Description and Values - Main PWB - Bottom Side Test Point Description Values 1 Tx UHF LO Lock voltage: ~1.2V 2 VR6 2.8V 3 Vbatt Cell* 4 Vbatt PCS* 5 VR1B 4.8V 6 AGC1 0.1V to 1.8V 7 AGC2 0.1V to 1.8V 8 VR6 2.8V 9 VR2 2.8V 10 VR1B 4.8V *Vbatt also appears at the outputs of the PAs.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 5 shows the values for the test points in Figure 19. Table 5: Tx DC Test Point Description and Values - Main PWB - Top Side Test Point Description Values 1 Power detector input AMPS: -5dBm at 836.25MHz Cell: -3dBm at 836.25MHz PCS: -6dBm at 1880MHz 2 Power detector output AMPS/Cell: 1.9V at <5dBm 1.8V at 15dBm 1.2V at 25dBm PCS: 1.9V at <5dBm 1.8V at 15dBm 1.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Tx RF Test Points - Bottom Side Figure 20 shows the Tx RF test points located on the bottom side of the main PWB. 3 5 4 1 2 Figure 20: Tx DC and RF test points on the bottom side of the main PWB Table 6 shows the values for the test points in Figure 20. These values are based on a PCS frequency of 1880MHz and an AMPS/Cell frequency of 836.25MHz.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 6: Tx RF Test Point Descriptions and Values - Main PWB - Bottom Side (Continued) Test Point Description Values 4 PCS PA out 11dBm 5 RF out AMPS: +14dBm Cell: +20dBm PCS: +20dBm RF Power Supply DC Test Points - Bottom Side Following are the RF power supply DC test points located on the bottom side of the main PWB.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 7 shows the values for the test points in Figure 21. Table 7: RF Power Supply DC Test Points (Main PWB - Bottom Side) Page 30 Probe Point Description Value 1 VIO 1.8V 2 VrefRF1 1.4V (Tx) 3 VR7 2.8V (Rx) 4 VR6 2.8V (Tx) 5 VR2 2.8V (Tx) 6 VR3 2.8V (Synthesizer) 7 VR5 2.8V (Rx) 8 VR4 2.8V (Rx) 9 VR1A 4.7V (Synthesizer) 10 VR1B 4.
Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Receiver RF Troubleshooting The heart of the receiver is the N7160 Rx IC, which contains two LNAs and mixers. The other components are passive. There are two RF SAW filters for the Cell and PCS bands. In addition, there are two additional IF filters, an IF SAW for CDMA and an IF Crystal for AMPS. The back-end of the receiver consists of the N7100 IC, which handles the VGA and IQ demodulator functions.
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting Receiver Block Diagram Following is the Rx system block diagram.
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting Receiver Schematics The following schematics are for general reference only. See the Schematics chapter for detailed versions.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Loop filter Rx LO lock voltage 1.2 to 1.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care RF AGC Status When configuring the values on the RF AGC Status dialog box, note the following: • The RF AGC status functionality only works in Call Mode. • In the PLL Lock Status area, bright green indicates a locked PLL and dark green indicates an unlocked PLL. • In the Baseband Type field, ensure that the correct baseband is selected (Tiku BB 4.5).
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Turning on the Rx Path Use the following steps to turn on the Rx path using Phoenix. 1. On the Phone Control dialog box, click the LOCAL button in the Phone State area to put the mobile terminal into Local Mode. Figure 26: Phone Control dialog box 2. Click the Execute button. 3. Depending on the band, use the applicable settings from the table below on the RF Main Mode dialog box.
Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Figure 27: RF Main Mode dialog box for AMPS (top), Cell (middle), and PCS (bottom) Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 37
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Switching the Rx Gain States Use the RF Gen I/O dialog box to switch the gain state (Hi and Lo) for CDMA and AMPS modes. High Gain State (default) Cell AMPS Low Gain State PCS CDMA Figure 28: RF Gen I/O dialog box Checking AMPS from RF to IQ Use the following steps to check the AMPS receiver functionality from RF to IQ output. 1. Start Phoenix in Local Mode with only the Rx path turned on. 2.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Figure 29: Receiver IQ Level on AMPS band Figure 30 shows the AMPS spectrum and the test points located on the top side of the main PWB. All four test points should be approximately equal. WARNING: Direct current is present on these test points.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care 3. Measure a 300kHz tone on the analyzer. You should see a typical -21dBm IQ tone for CDMA Cell. Cell I Q Output Trace A dBm 1 0 -10 Trace A 302 kHz -21.2500 dBm 1 -20 -30 -40 -50 -60 -70 -80 -90 -100 Centre: 300 kHz Res BW: 3 kHz 5/5/2004 3:29:30 PM Atten: 10 dB Vid BW: 3 kHz CellIQ.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Checking PCS Receiver from RF to IQ Use the following values to check the PCS receiver functionality from RF to IQ output. 1. Start Phoenix in Local Mode with only the Rx path turned on. 2. Inject a –75dBm CW signal of 1960.5MHz (i.e. 500kHz offset from 1960MHz or 10 channels away). 3. Measure a 500kHz tone on the analyzer.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Rx_QP Rx_QN Rx_IP Rx_IN Figure 34: PCS spectrum and the test points on the top side of the main PWB Receiver Diagnostic Signal Tracing Use the following steps to trace the receiver signal. 1. Inject an external signal source of –25dBm to the RF input. An Agilent call box 8960 is recommended. 2. Press the Call Setup button, press the Active Cell soft button, and select CW. 3.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Receiver DC Test Points 1 4 7 6 2 3 5 Figure 35: Receiver DC troubleshooting test points on the bottom side of the main PWB Table 9 includes the descriptions and values for the Rx DC test points from Figure 35. Table 9: Receiver DC Test Point Values Test Point Description Value 1 Rx LO lock voltage 1.2 to 1.7 Vdc 2 LO Vdd 2.6 VDC LO Amp supply lines for Cell and PCS 3 RFA Vdd 2.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Receiver RF Test Points 1 7 6 3 2 4 5 Figure 36: Rx RF test points on the bottom side of the main PWB Table 10 includes the descriptions and values for the Rx RF test points from Figure 36. Table 10: Receiver RF Test Point Values Page 44 Test Point Description Value 1 PCS_CEL_LO (from VCO) Cell: 1009.62MHz at -15dBm PCS: 2088.1MHz at -17dBm 2 Cell channel 384 (from duplexer) 881.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 10: Receiver RF Test Point Values (Continued) Test Point Description Value 5 PCS channel 600 (to RF SAW) High gain: 1960MHz at -32dBm Low gain: 1960MHz at -49dBm 6 IF MIX OUT (from N7160) High gain: 128.1MHz at -21dBm Low gain: 128.1MHz at -34dBm 7 IFA_IN (to N7160) High gain: 128.1MHz at -18dBm Low gain: 128.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 11: Receiver IF Test Point Values (Continued) Test Point Description Value 3 CDMA_IF_P (to the N7100) 128.1MHz Cell high gain: -29dBm Cell low gain: -45dBm PCS high gain: -29dBm PCS low gain: -45dBm 4 CDMA_IF_N Cell high gain: -29dBm Cell low gain: -45dBm PCS high gain: -29dBm PCS low gain: -45dBm 5 AMPS IF (to MCF) 128.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 12 includes the measure logic levels for the N7160. Table 12: Rx Front-end (N7160) Logic Levels Mode Logic Input Voltages IF_SEL BAND GAIN_CTL AMPS High Gain 2.8 V 0.1 V 2.8 V AMPS Low Gain 2.8 V 0.1 V 0V Cell CDMA High Gain 0V 0.1 V 2.8 V Cell CDMA Low Gain 0V 0.1 V 0V PCS CDMA High Gain 0V 2.7 V 2.8 V PCS CDMA Low Gain 0V 2.7 V 0V If the logic levels are significantly off (+/- 0.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Cell RFA IFAs LO Buffer PCS RFA Cell LNA PCS LNA Figure 39: N7160 receiver There are two common explanations for an N7160 failure consisting of high current in Local Mode with just the Rx turned on: • No presence of an LO signal • Input impedance drop is shorting out one of the DC supply pins to the chip IMPORTANT: You must check for both conditions before replacing the chip.
Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Synthesizer Troubleshooting Faulty synthesizers can cause both Rx and Tx failures during tuning, in addition to the VCTCXO tuning. However, first check for the presence of various LO signals and their proper levels. If everything fails, it may be necessary to check the reference clock (19.2MHz) which is needed for the mobile terminal to power up. The 19.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Synthesizer Block Diagram Rx VHF LO 256.2MHz N7100 UHF LO 1009.62MHz (Cell ch. 384) 2088.1MHz (PCS ch. 600) N7160 N7200 Tx UHF LO 3395.88MHz 3819.
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting Synthesizer Schematics The following schematics are for general reference only. See the Schematics chapter for detailed versions. 19.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Synthesizer Troubleshooting Setup Use the following steps to troubleshoot the synthesizer using Phoenix: 1. On the Phone Control dialog box, click the LOCAL button in the Phone State area to put the mobile terminal into Local Mode. Figure 42: Phone Control dialog box 2. Select the following values on the RF Main Mode dialog box:.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care VCTCXO Troubleshooting Without 19.2MHz, the mobile terminal does not power up. This signal goes to the N7100, N7000, D2800, and the UHF PLL. Check the test points in Figure 43 for the presence of the 19.2MHz signal. Dual-band VCO 7 3 UHF PLL IC 1 VCTCXO 8 4 2 6 5 Figure 43: VCTCXO test point output values Table 15 includes the descriptions and values for VCTCXO test points from Figure 43.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 15: VCTCXO Test Point Output Values (Continued) Test Point Description Value 7 If you do not see the VCTCXO signal at test points 1-5, check the voltage at VR3 2.8V 8 AFC voltage 1 to 3 Volts (adjustable with the AFC slider on the RF PDM Control in Phoenix) 1.2V for PDM 0 0V for PDM -1024 2.4V for PDM 1024 N/A If an AFC voltage is missing, check the UEM.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care AFC Voltage Troubleshooting Use the following steps to monitor the AFC voltage. 1. In Phoenix, open the RF PDM dialog box. Figure 44: RF PDM dialog box for AFC troubleshooting Figure 45 shows a partial schematic of the R7205. Figure 45: Partial schematic showing the R7205 2. Measure the DC voltage at R7205. The following typical voltages are shown in Figure 46. • 1 = AFC PDM[-1024]=0V • 2 = AFC PDM[0]=1.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Figure 46: Tx Output for AMPS channel 384, power level 5 UHF Synthesizer The UHF LO frequency varies with the channel and can be calculated using the Frequency Calculator dialog box in the Phoenix RF component. Use the following steps to troubleshoot the UHF LO frequency. 1. Ensure that the LO is locked. Set a channel and check the output of the UHF LO at L7200 within a very narrow span of 100KHz.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care UHF Synthesizer Test Points N7100 1 7 5 6 4 2 3 Figure 47: UHF synthesizer layout Table 16 shows the description for each component in Figure 47. Table 16: UHF Synthesizer Layout Components Test Point Description Value 1 BAND_SEL_VCO Cell = 0Vdc PCS = 2.8Vdc 2 PCS_CEL-LO return to UHF PLL Cell: -11dBm PCS: -18dBm 3 PCS_CEL_LO input to the N7160 Cell channel 384: 1009.62MHz > -15dBm PCS channel 600: 2088.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Rx VHF LO (N7100) Schematic Following are the main layout components on a partial view of the Rx VHF schematic. See the Schematics chapter for detailed versions.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Rx VHF LO Troubleshooting The VHF LO operates at a fixed frequency of 256.2MHz. It is the second LO for downconversion to I and Q for baseband processing. Use the following steps to troubleshoot the VHF LO. 1. Monitor the test point at C710. Ensure that a locked and stable 256.2MHz with amplitude ~ –60dBm is present on the spectrum analyzer (or, with a high impedance probe, ~ -2dBm at C7104). 2.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Tx UHF LO (N7000) Schematic The following partial schematic is for general reference only. See the Schematics chapter for complete detailed versions.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Tx UHF LO (N7000) Troubleshooting There are two fixed LOs, 3296.16~3395.88MHz for cell band and 3700~3819.90MHz for PCS band. This is the only LO for up-conversion. Be sure to monitor the control voltage at R7001. When the N7000 LO is locked, this control voltage should be between 1.2 and 1.8Vdc.
55/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care GPS Troubleshooting GPS RF Block Diagram Figure 52: GPS block diagram Page 62 ©2005 Nokia Corporation Company Confidential Issue 2 05/2005
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting GPS RF Schematic The following schematic is for general reference only. See the Schematics chapter for a detailed version.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care GPS Troubleshooting Setup Use the following steps to set up GPS signal using Phoenix. 1. On the Phone Control dialog box, click the LOCAL button in the Phone State area to put the mobile terminal into Local Mode. (See Figure 9 on page 16 for an example of the Phone Control dialog box.) 2. Click the Execute button. 3. Inject a -110dBm tone at 1575.52MHz at the GPS connector (X6250) with a signal generator or call box.
Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting 5. In the Test Mode field, ensure that Galvanic is selected. 6. Click Execute. Self Test Failure If the test fails, repeat steps 1—6. If the test fails again, continue with the following selftest failure troubleshooting: 1. Verify the DC voltages at VRF_GPS and VIO_GPS. ("GPS DC Test Points" on page 66 for test point locations and values.) 2. Inspect all GPS circuit elements around the GPS BB chip (N6200). 3.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care 2. Click Execute. Figure 56: Turning on the GPS receiver on the GPS Control dialog box 3. Inject a -50dBm tone at 1575.52MHz at the GPS connector (X6250) with a signal generator or a call box. (See Figure 54.) GPS DC Test Points Measure the following test points with an AAS-10B probe and spectrum analyzer set at center frequency 1575.25MHz (span = 500kHz), or with a voltmeter as required.
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting GPS RF connector GPS RF IC BOTTOM SIDE TOP SIDE GPS ceramic antenna 1 Ceramic filter GPS BB IC 3 GPS TCXO SAW filter 2 4 Figure 57: GPS DC probe points on the bottom side (left) and top side (right) of the UI PWB Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 67
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 19 shows the values for the GPS DC test points in Figure 57. Table 19: GPS DC Test Point Values Page 68 Test Point Description Value 1 VIO 1.8V 2 VRF_GPS 2.8V 3 LNA base 0.8V 4 LNA Vcc 1.
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting GPS RF Test Points GPS RF connector 1 BOTTOM SIDE TOP SIDE GPS ceramic antenna GPS RF IC Ceramic filter GPS BB IC 3 4 2 GPS TCXO SAW filter 2 2 Figure 58: GPS RF probe points on the top side of the UI PWB Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 69
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Table 20 shows the values for the GPS RF test points in Figure 58. All points are 1575.52MHz, except TCXO. Table 20: GPS RF Test Point Values Page 70 Test Point Description Value 1 GPS TCXO 16.368MHz = -19dBm 2 GPS TCXO 16.
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting FM Radio Troubleshooting FM Radio Schematic The following schematic is for general reference only. See the Schematics chapter for a detailed version.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care FM Radio Troubleshooting Setup Use the following steps to troubleshoot the FM radio while using a Pop-port headset. 1. Connect the Pop-port headset (HDS-3) to the Pop-port connector (bottom connector). 2. Select the Menu > Media > Radio from the mobile terminal user interface. 3. In an FM radio broadcast coverage area, set a local radio channel by scanning automatically using the Automatic tuning option.
Nokia Customer Care 6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting FM antenna matching components Figure 60: FM radio parts on the top side of the main PWB Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 73
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting FM radio circuitry Nokia Customer Care FM radio IC FM audio coupling caps Figure 61: FM radio parts on the bottom side of the main PWB Page 74 ©2005 Nokia Corporation Company Confidential Issue 2 05/2005
6255/6255i/6256/6256i (RM-19) Nokia Customer Care RF Description and Troubleshooting Bluetooth Troubleshooting Bluetooth Schematic The following schematic is for general reference only. See the Schematics chapter for a detailed version.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Bluetooth Troubleshooting Setup Use the following steps to troubleshoot the BC02 Bluetooth Control component in Phoenix: 1. On the Bluetooth Control dialog box, select the Tests tab. 2. In the PRBS9 list, choose TX Data 1. 3. For easy power measurement, choose “TX Simple” – 62.5kHz FM. 4. Click on “Options” button. 5. Set Internal gain = 52 6.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Bluetooth Troubleshooting Flowchart Bluetooth Is the VREG_IN BT external supply voltage 2.8V? NO Replace the EXT regulator. Is it OK? NO Replace the R6002. Is it OK? NO YES Is the VIO bluetooth external supply voltage 1.8V? (Probe at the UEM side.) NO YES Is the VDD_ANA voltage regulator output 1.8V? Replace the BT ASIC (N6000). NO YES Is the XTAL_IN 450mVpp, 19MHz, 1.
6255/6255i/6256/6256i (RM-19) RF Description and Troubleshooting Nokia Customer Care Bluetooth DC and RF Test Points Figure 63 shows the bluetooth DC and RF test points on the bottom side of the main PWB. 1 2 Digital inverter 3 4 Voltage regulator Figure 63: Bluetooth DC and RF test points on the bottom side of the main PWB Table 23 shows the values associated with the bluetooth test points in Figure 63.
