Nokia Customer Care RH-51/52, RH-67/68 Series Cellular Phones 6(b) - RF Troubleshooting and Manual Tuning Guide Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care This page has been deliberately left blank Page 2 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Table of contents Page No Introduction ............................................................................................................................................... 7 General troubleshooting ..................................................................................................................... 7 RF key component placement....................................................................
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care This page has been deliberately left blank Page 4 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting List of figures Page No Fig 1 RF key components.........................................................................................................................9 Fig 2 RF key components.........................................................................................................................9 Fig 3 Receiver signal path ................................................................................
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care This page has been deliberately left blank Page 6 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Introduction This document describes troubleshooting and RF tuning of RH-51/52, RH-67/68.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care For example, when transmitting in the EGSM band at max power level, the output power will be around +33dBm. By using a 10dB attenuator the actual input to the SA will then be +23dBm. Also adjust the internal attenuator so that the transmitted signal is reduced to less than around -10dBm in order to avoid saturation of SA input stage.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting RF key component placement The following figure shows the key components of the RF section.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Receiver troubleshooting General description Figure 3: Receiver signal path Page 10 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Each receiver path is a direct conversion linear receiver. From the antenna, the received RF signal is fed to a front end module where a diplexer first divides the signal to two separate paths according to the band of operation: either lower, GSM850/EGSM900 or upper, GSM1800/1900 path. At each of the paths follows a pin-diode switch, which is used to select either a receive- or transmit mode.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care ADCs. The maximum peak-to-peak voltage swing for the ADCs is 1.45 V.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Apply a signal with frequency of EGSM900:942.4677MHz (channel 37 + 67.7KHz offset) GSM850: 881.667MHz (channel 190 + 67.7KHz offset) GSM1800:1842.8677MHz (channel 700 + 67.7KHz offset) GSM1900:1960.0677MHz (channel 661 + 67.7KHz offset) and a power level of –80dBm to the RF connector (remember to compensate for cable loss). In RSSI reading, click Read now. The resulting RSSI level should be –80dBm in each band.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Measuring RX performance using SNR measurement Note: This measurements also provides an indication of the conducted sensitivity Start Phoenix Service Software and establish connection to the phone Select File ->Open Product RH-51, -52, -67 or -68 Select Testing ->RF controls Select Band ->GSM850 / GSM900 / GSM1800 / GSM1900 Active unit ->RX Operation mode ->Burst RX/TX channel -> EGSM900: 37 GSM850: 190 GSM1800:
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Measuring the RX module manually using oscilloscope and spectrum analyzer Spectrum analyzer level values depend on the probe type and should be validated using a known good sample. The levels that are given here are measured using a high frequency probe.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Input freq/level of signal generator is 942.4677MHz, -60dBm (881.6677MHz for GSM850) Note: Because DC compensation doesn’t work during continuous mode, DC offset level at RXI and RXQ will gradually shift from the optimized level. To have most reliable result, it is highly advisable to set operation mode from burst to continuous just before measuring values and complete measurement within no longer than 30 seconds.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Figure 5: Probed RX I/Q signals J827, 828 Signal amplitude 180 ~ 600mVpp DC offset 1.2 ~ 1.4V Frequency approx 67KHz GSM1800 Start Phoenix Service Software and establish connection to the phone. Select File Open Product RH-51, -52, -67 or 68 Select Testing RF controls Select Band Active unit RX Operation mode Continuous * RX/TX channel 700 AGC 12 Issue 3 09/2004 GSM1800 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Input freq/level of signal generator is 1842.8677MHz, -60dBm Note: Because DC compensation doesn’t work during continuous mode, DC offset level at RXI and RXQ will gradually shift from the optimized level. To have most reliable result, it is highly advisable to set operation mode from burst to continuous just before measuring values and complete measurement within no longer than 30 seconds.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting GSM1900 Start Phoenix Service Software and establish connection to the phone. Select File Open Product RH-51, -52, -67 or -68 Select Testing RF controls Select Band GSM1900 Active unit RX Operation mode Continuous * RX/TX channel 661 AGC 12 Input freq/level of signal generator is 1960.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Figure 7: Troubleshooting chart for GSM1900 Apply -60 dBm 1960.0677 MHz from generator to antenna connector YES GSM1900 chain functional Check RSSI using Phoenix Does it match Sig Gen Output level ? NO NO Is L.O running at 3920.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Measurement points in the receiver Figure 8: Measurement points at RX frontend - part 1 L802, 803 output L804, 805 output C805, 806 output Z803 output T800 output Z802 output Figure 9: Measurement points at RX frontend - part 2 V800 output Z800 VC2 Z800 GSM1900 output Z800 VC1 Z801 output Z800 GSM1800 output Z800 EGSM900 (GSM850) output Z800 VC3 Z800 input Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Figure 10: Measurement points at baseband IQ J827 RXI J828 RXQ Figure 11: Measurement points at digital IQ J261 RXID J262 RXQD Page 22 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Tuning RX using Phoenix RX channel select filter calibration This calibration calibrates the baseband filter inside Helgo ASIC. It is done by internally measuring a prototype filter, for this reason the calibration is done once, not separately 3 bands. This tuning doesn’t require RF input from an external signal generator.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Check Automatic calibration mode. Check load from phone and Save to phone. Press Start Initial data will be loaded from the phone and calibration starts. You will see following banner pops up. Follow the instructions in the pop–up window and set frequency and level of the signal generator Press Page 24 OK © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care Press RH-51/52, RH-67/68 6(b) - RF Troubleshooting “Save & Continue” Calibration data will be stored to the phone and continue to the next band. RX band filter response compensation Rx band filter response compensation has 9 steps for each band. Rx band filter response compensation requires an external signal generator. Select Issue 3 09/2004 Tuning RX Band Filter Response Compensation © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Select Company Confidential Nokia Customer Care Manual Tuning mode Press Start. Initial data will be loaded from the phone. Press tune to start calibration. Follow the instructions given in the following pop–up window and set frequency and level of the signal generator. Press OK to proceed to the next step. After completely the 9 steps –calibration at 9 frequencies. Test will be repeated for other bands. Page 26 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Transmitter troubleshooting General description A simple block diagram of the TX part of the phone is shown in the following figure. The voice or data signals to be transmitted come from the UEME IC in the BB (baseband) area, and go to the Helgo IC, where they are up-converted to RF.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care (E)GSM SAW filter Helgo DCS/PCS Balun ASM Power Amplifier hh Preparation for troubleshooting • Place the phone (mechanics removed) on module jig. • Connect the module jig to the PC via a DAU-9P cable. • Connect the module jig to a power supply (4.2V). • Connect the RF output to a spectrum analyzer or another measurement instrument. Use a 10dB attenuator at the input to spectrum analyzer to avoid damaging it.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Phoenix should now look like this: Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Fault-finding chart: TX-BB interface and control signals Figure 13: Troubleshooting chart of TX-BB interface and control signals Figure 14: Oscilloscope screen shots Typical oscilloscope plots of the four TXIQ-lines: VTXB_900 zoom 0.5Vpp 4.615ms 2.7V 1.1Vdc ~67kHz waveform for all 1's Ctrl signals to ASM: ( DCS/PCS ) TXC-signal 2.7V TXP-signal Cont1 6 4.615ms 4. Cont2 EGSM900 channel = 37 PL = 5 Page 30 4.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Fault-finding chart: RF side of transmitter Figure 15: Troubleshooting chart of RF side of transmitter Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care VPCTRL 1800_1900 PA 1800/ 1900 Output PA 1800/ 1900 Input VBAT BT D190 PA 850/ 900 Input ASM Output PA 850/900 Output VPCTRL 900 TXP J813 UPP D370 Page 32 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Transmitter tuning In the transmitter there are two kinds of tunings that can be done; IQ tuning and power level tuning. In general, different repairs require different tunings. In order to decide which tuning is necessary after a repair, it is important to understand well the functionality of the repaired circuit. In general, it is recommended that if any TX component is changed, both these tunings be done.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Figure 16: Phoenix set-up (RF Controls menu) Figure 17: Phoenix set-up (Tx IQ Tuning menu) Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care After opening the two before-mentioned windows, Phoenix should look like this: Figure 18: Phoenix set-up (Tx IQ Tuning windows) The following table summarizes the settings of the RF control window for IQ tuning of the three bands.
Company Confidential RH-51/52, RH-67/68 6(b) - RF Troubleshooting Nokia Customer Care Figure 19: Spectrum analyzer screen shot when performing IQ tuning, part 1 RBW 3 kHz Ref Lvl 33.35 dBm VBW 3 kHz 35 dBm 897.33229000 MHz 1 SWT 3 s Marker 1 [T1] 35 27.5 dB Offset Unit 1 [T1] 30 RF Att 30 dB dBm 33.35 dBm A 897.33229000 MHz 2 [T1] 20 -6.76 dBm 897.40000000 MHz 3 [T1] -10.74 dBm 897.46771000 MHz 10 1MA 0 2 3 -10 -20 -30 -40 -50 -60 -65 Center 897.4 MHz Date: 14.JAN.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Figure 20: Spectrum analyzer screen shot when performing IQ tuning, part 2 Ref Lvl VBWRBW Marker 133.40 [T1] dBm 897.33229000 MHzdBm SWTVBW 33.40 1 35 35 dBm SWT 897.33229000 MHz 27.5 dB Offset 1 30 35 27.5 dB Offset 35Ref dBmLvl 30 20 3 kHz 3 kHz RF Att 3 3 s kHz Unit 3 s 1 [T1] 30 dB dBm Unit dBm 33.40 dBm A 897.33229000 MHz dBm 1 [T1] 33.40 2 [T1] -20.35 dBmMHz 897.33229000 A 897.40000000 MHz dBm 2 [T1] -20.
Company Confidential RH-51/52, RH-67/68 6(b) - RF Troubleshooting Nokia Customer Care TX power level tuning This tuning is done separately in all three bands, and requires a spectrum analyzer to measure the burst power of the GSM RF signal. When measuring the RF output (burst) power on a spectrum analyzer, use the settings found in the following table: Table 3: Spectrum analyzer settings for Tx power level tuning GSM850 GSM900 GSM1800 GSM1900 Center frequency 836.6MHz 897.4MHz 1747.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Phoenix should now look similar to the figure below. Figure 22: Phoenix Power Level Tuning menu Connect the module jig RF output to the measurement instrument. The power must be tuned in only high TX PA mode in all bands of GSM850, GSM900, GSM1800 and GSM1900.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting culate coefficients’ to calculate the other power levels with non-bold letters. When the coefficient calculation was done successfully, then press ‘Save & Continue’ to save the new tuning values into the phone memory. The following figure shows the power level tuning at the GSM900 band.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Figure 24: Spectrum analyzer screen shot during power level tuning Page 42 © 2004 Nokia Corporation.
Company Confidential RH-51/52, RH-67/68 6(b) - RF Troubleshooting Nokia Customer Care Synthesizer troubleshooting General description LPRFCLK RFCLK /*\ NQQR HKNVGT 8%1 AFC RFBusData RFBusClk RFBusEna1 Reset Figure 25: Synthesizer block diagram Issue 3 09/2004 ‡” 1/4 1/2 4&+8 CNTROL 0&+8 #&+8 1/4 1/2 PLL_BLOCK M EJCTIG RWOR 1/2 HELGO RF ASIC © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care The PLL is capable of tuning frequency range for GSM band 850/900/1800/1900. Hence PLL is common in all variants. The VCO frequency is locked by a PLL (phase locked loop) into a stable frequency source given by a VCTCXO, which is running at 26 MHz.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Figure 26: RF key component. Figure 27: Synthesizer key components without shielding frame VCTXO 26MHz G500 Balun 3-4GHz T500 VCO 3-4GHz G500 Assumption No failure i.e. soldering or component failure for simple SMD components such as resistors, inductors and capacitors.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Preparation for troubleshooting • Place the phone (mechanics removed) on module jig. • Connect the module jig to the PC via a DAU-9P cable. • Connect the module jig to a power supply (4.2V). • Connect the RF output to a spectrum analyzer or another measurement instrument. • Use a 10dB attenuator at the input to spectrum analyzer to avoid damage. • Make sure the dongle is connected and start Phoenix.
Company Confidential RH-51/52, RH-67/68 6(b) - RF Troubleshooting Nokia Customer Care Measuring the synthesizer manually using spectrum analyzer Spectrum analyzer level values depend on the probe type and should be validated using a known good sample. The levels that are given here are measured using a high frequency probe. Spectrum analyzer should be at least capable of measuring signal upto 4.5 GHz.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Figure 30: Measurement points for synthesizer. Layout shows HELGO/VCO compartment. C526 VCTCXO Vcc G501 VCTCXO Output HELGO N500 Balun +/- Output T500 G516 VR1=Vcp C517 VR5=Vpre G500 VCO RF Output Figure 31: Measurement points for synthesizer. Layout shows UEME compartment UEME D250 Page 48 © 2004 Nokia Corporation.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Bluetooth troubleshooting This document describes BC02 bluetooth solution troubleshooting for Care. Applicable parts can be copied to phone products’ service document. It is assumed that the main service manual includes part “How to connect Phoenix to phone”.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care 3 Choose: Testing −> Bluetooth LOCALS 4 Locate JBT-9’s Ser.No. (12 digits from the type label) found in the type label in the back of JBT-9. 5 In the Bluetooth LOCALS setting enter Ser.No. for the “Counterpart Device Address” field. This has to be done only once provided JBT-9 is not changed. 6 Run BER test when JBT-9 box is proximity of the DUT’s Bluetooth antenna. Suitable distance is approximately 10 centimeter.
Company Confidential Nokia Customer Care RH-51/52, RH-67/68 6(b) - RF Troubleshooting Figure 33: Phoenix settings for Bluetooth troubleshooting Issue 3 09/2004 © 2004 Nokia Corporation.
RH-51/52, RH-67/68 6(b) - RF Troubleshooting Company Confidential Nokia Customer Care Bluetooth troubleshooting diagram Figure 34: Bluetooth troubleshooting flowchart Bluetooth fault Connection to Y JBT9 OK ? N BER <= 0.1%? N 1) Y Bluetooth ok Check component soldering in RF path (Z191, Z192, C191, C192, L191, L192) 2) Replace balun and filter (Z191, Z192) 3) Is BC02 VREG_IN = 2.8V at C203? Replace BC02 (D190) N Y Vflash1 from UEME not supplied Replace BC02 (D190) N Is BC02 VDD_ANA = 1.
