CCS Technical Documentation RH-48 Series Transceivers Troubleshooting - RF Issue 1 11/2003 Confidential © 2003 Nokia Corporation
RH-48 Troubleshooting - RF CCS Technical Documentation Contents Page No RF Troubleshooting ........................................................................................................3 RH-48 General Troubleshooting Notes ........................................................................3 Phone Components .......................................................................................................4 Phone Cannot Make a Call........................................................
RH-48 Troubleshooting - RF CCS Technical Documentation RF Troubleshooting RH-48 General Troubleshooting Notes First check the RX AGC PDM value when troubleshooting the receiver. 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.
RH-48 Troubleshooting - RF CCS Technical Documentation Phone Components Figures 1 and 2 illustrate the main components of the RH-48.
RH-48 Troubleshooting - RF CCS Technical Documentation Cell Duplexer On/Off Switch Cell Isolator Rx IC “Alfred” LNA+Downconverter PA PMIC DC-DC Converter Cell Rx RF SAW Filter Cell Tx PA Cell Tx SAW Filter Jedi Tx Up-Converter Battery Converter YODA Rx DownConverter VCO VCTCXO Rx IF CDMA Filter UEM (B.B) UPP (B.
RH-48 Troubleshooting - RF CCS Technical Documentation • The SID is correct and entered into the phone. • The MIN and MDN are entered into the phone. • The VCTCXO is centered as described in the VCTCXO tuning description on page 31. • The transmitter and receiver are working properly in Local Mode. Transmitter Troubleshooting Low Tx Power Use Phoenix to turn on the transmitter in local mode, and check the following: 1 Verify the current (0.7 - 1A for max power, mode, and channel dependent).
RH-48 Troubleshooting - RF CCS Technical Documentation Cell Transmitter Setup Use the following steps to set up the phone for Tx troubleshooting in Phoenix. 1 Open the Phone Control dialog box. Figure 3: Phone Control dialog box for Tx troubleshooting 2 Click the LOCAL button in the Phone State area to put the phone into Local Mode.
RH-48 Troubleshooting - RF 4 CCS Technical Documentation Click the Set button. Note: Be sure that the “RF Main Mode set successfully...” message appears in the status bar. 5 Page 8 Select the Rho ON check box on the CDMA Control dialog box. Figure 5: CDMA Control dialog box for Tx troubleshooting 6 Click the Execute button. 7 At this point you should be able to measure Tx Pout at the RF connector. The cell band Tx Pout =0 to 2dBm.
RH-48 Troubleshooting - RF CCS Technical Documentation 9 Enter 10, 13, 12, and 8 in the PIN # fields. Figure 6: General I/O dialog box for Tx troubleshooting 10 Select the boxes in the Enable column for each pin. 11 Click the Get All button. 12 Ensure that all of the pins have a value of H in the State column. (Click the L values to change them to H values.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 7: RF PDM dialog box for Tx troubleshooting 14 Ensure that the Phone Tx Pout = +25dBm and the current = 770-860mA. Cell Transmitter Path The following table indicates the test points to probe when troubleshooting the cell transmitter path. It is recommended that you follow the steps in order. An HP high frequency probe was used to make the frequency and output power measurements.
RH-48 Troubleshooting - RF CCS Technical Documentation Cell Transmitter Test Path Part* Function Typical Value/ Frequency HP85024A T8 C636L, C624T, L609B, C612L, C630B, L607B VR2 2.7V dc Mixer, driver, and IF supply from UEM T9 C605R, C606R VAGC-Tx 0.2 to 1.8V dc Tx AGC Control Voltage from UPP. 0.2V = Max Gain 1.8V = Min Gain T10 C658R, C600T VIO-Tx 1.8V dc Supply for Digital circuits from UEM T11 C805B, C810T, C816R VBAT 3.6V dc Battery Voltage (Nominal Voltage 3.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 8 shows each testing point from the Cell Transmitter Test Path table for the Jedi TXIC section. Always attach a 20dB pad (11881-60001) when probing with an HP85024A high frequency probe. Figure 8: (Top) PWB. (Bottom left) A zoomed view of the testing points on the Jedi TXIC section. (Bottom right) A zoomed view of the Jedi TXIC section with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 9 shows each testing point for the PA section from the Cell Transmitter Test Path table on page 10. Always attach a 20dB pad (11881-60001) when probing with an HP85024A high frequency probe. Figure 9: (Top) PWB. (Bottom left) A zoomed view of the testing points on the PA section. (Bottom right) A zoomed view of the PA section with part numbers. Tx AGC Tuning Tx power versus IF/RF PDM can be verified against FlaLi specification limits.
RH-48 Troubleshooting - RF CCS Technical Documentation Tx AGC Tuning Tx Tuning AGC Step Tx AGC PDM Value Target Power Low Limit High Limit Tx AGC (6) -94 15 6 24 Tx AGC (7)* -280* 25 21 27 Cell Power Amplifier The power amplifier (PA) has the DC/DC converter (PMIC device), which controls the transmitter. The following tables show the circuits that have an effect on the transmitter path and how to troubleshoot them.
RH-48 Troubleshooting - RF CCS Technical Documentation Cell PMIC The following tables show the PMIC troubleshooting information. PMIC Setup: Mode Tx Rx Band Local On On CELL PMIC Measurements: Pin Label Test Point Units Depends on Comments 1 EP Pin 1 1.8 UPP IC enable = GenIO 10 2 M0 Pin 2 1.8 UPP Control 0 = GenIO 12 3 M1 Pin 3 1.8 UPP Control 1 = GenIO 13 4 NC NC NC NC NC 5 FB Pin 5 0.75 - 4 M0, M1 See PA worksheet. Output to flyback inductor. 6 FB Pin 6 0.
RH-48 Troubleshooting - RF CCS Technical Documentation Good phone PMIC Resistances Page 16 Pin Resistance 4 1.59M 5 1.6M 6 2M 7 2M 8 2M 9 0.1 10 100 11 115k 12 60k 13 0.2 14 1.3M 15 1.18M 16 0.
RH-48 Troubleshooting - RF CCS Technical Documentation Cell IF/RF AGC and PA Control The following Cell CDMA Channel 384 (Skyworks PA) table illustrates the PDM values and their typical values for the IF AGC, RF AGC Jedi Pout, gain steps, and the PA VCC levels. This table also shows the typical power output at the RF connector. Cell CDMA Channel 384 (Skyworks PA) Tx RF AGC Tx IF AGC PA Gain Step Jedi Po PA Vcc Conn RF Pout Gen IO 12 Gen IO 13 Typical Value Test Point PA Gain H H 3.
RH-48 Troubleshooting - RF CCS Technical Documentation Cell Power Measurements: Cell, Channel 384 Tx ADC PA Gain Step RF/IF pdm GIO 12 GIO 13 324 L L 142 L 17 Conn RF Pout Power Detector Comments Pout at detector Test Point -50 -86.3 right R814 L -25 -63 2 235 L L 0 -41 1.998 235 -48 L L 6 -30 1.967 250 -48 H L 7 -29 1.957 268 -95 H L 11 -26 1.93 286 -95 H H 13.2 -23.5 1.9 435 -146 H H 17 -21.5 1.86 486 -178 H H 19 -19 1.
RH-48 Troubleshooting - RF CCS Technical Documentation Tx System Block Diagram Figure 10 illustrates a simplified block diagram of the transmitter. The figure shows every major component from I and Q baseband to the antenna port. Note: See the Schematics chapter for an RH-48 transmitter schematic. Figure 10: Tx system block diagram Receiver Troubleshooting Rx IF Use Phoenix to perform the following steps for troubleshooting the receiver.
RH-48 Troubleshooting - RF CCS Technical Documentation 2 Open the Phone Control dialog box.. 3 Click the LOCAL button in the Phone State area to put the phone into Local Mode. 4 Select the following values on the RF Main Mode dialog box: Figure 11: Phone Control dialog box for Rx IF troubleshooting • Band = Cell (CDMA) • Channel = 384 • Mode = Rx 5 Figure 12: RF Main Mode dialog box for Rx IF troubleshooting Click the Set button. Note: Be sure that the “RF Main Mode set successfully...
RH-48 Troubleshooting - RF CCS Technical Documentation 6 Use a spectrum analyzer to test TP3 (I+,I-, Q+, Q-). Set the S.A to 300KHz center frequency, 200KHz SPAN, and +10dBm reference level. The spectrum analyzer should read –8dBm without any settings to the PDM. Use the following CDMA Generator Code Domain Setup table to configure the CDMA generator code domain. CDMA Generator Code Domain Setup Channel Power Walsh code Pilot -7dB 0 Paging -12dB 1 Traffic -15.
RH-48 Troubleshooting - RF CCS Technical Documentation Rx IF Troubleshooting Step # Part* Function Typical Value/ Frequency HP85024A Typical Value Frequency Prod Probe TP9 R703T (R701L, R715T) VR7 2.7Vdc VHF VCO Supply from UEM TP10 C734B VR3 2.7Vdc VCTCXO buffer supply from UEM. TP11 C712R, C744R VR6 2.7Vdc Main supply to N700, from UEM. TP12 C710T, C704B VIO 1.8Vdc Digital circuits supply from UEM.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 13 shows each testing point from the Rx IF Troubleshooting table for the Rx IF section. Figure 13: (Top) PWB. (Bottom left) A zoomed view of the testing points on the Rx IF section. (Bottom right) A zoomed view of the Rx IF section with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Switching the Gain Use the following steps if the receiver is not working properly and you need to switch the Rx gain state. 1 Open the Phone Control dialog box. 2 Click the LOCAL button in the Phone State area to put the phone into Local Mode.
RH-48 Troubleshooting - RF CCS Technical Documentation 4 Click the Set button. Note: Be sure that the “RF Main Mode set successfully...” message appears in the status bar. 5 Connect a signal generator in CW mode (881.52MHz, -25dBm) to the RF connector. If you do not have a generator, use the Call Box Amps Mode RF Generator, Channel 384, -25dBm and set the FM modulation to 100Hz, deviation 400Hz. 6 To switch the Rx gain states, open the RF Register R/W dialog box.
RH-48 Troubleshooting - RF CCS Technical Documentation Rx RF The following Rx RF Troubleshooting table indicates the test points to probe when troubleshooting the Rx RF. It is recommended that you follow the steps in order. Rx RF Troubleshooting Typical Value/ Frequency HP85024A Typical Value Frequency Prod Probe RF-IN -25dBm/ 881.52MHz -42dBm 881.52MHz Input Connector reference level L906L LNA-In -35dBm/ 881.52MHz -42dBm 881.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 17 shows the Rx RF testing points from the Rx RF Troubleshooting table. Antennae Connector (other side) R1 Figure 17: (Top left) PWB. (Top right) The antenna connector on the opposite side of the PWB, (Bottom left) A zoomed view of the testing points on the Rx RF section. (Bottom right) A zoomed view of the Rx RF section with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Rx AGC (Cell mode) The following Rx RF AGC PDM vs AGC Voltage table shows the Rx RF AGC PDM vs AGC voltages in local mode on channel 384. Rx RF AGC PDM vs AGC Voltage Rx RF AGC PDM Typical Value Test Point -512 0.08 right R702 -400 0.260 -300 0.436 -200 0.597 -100 0.753 0 0.913 100 1.076 200 1.24 300 1.403 350 1.494 400 1.570 500 1.740 511 1.
RH-48 Troubleshooting - RF CCS Technical Documentation Rx AGC vs RF Pin for CELL Band Conn RF Pin CELL RF AGC -95 0..633 -100 0.594 -105 0.524 -107 0.470 UNITS VDC Comments Note the reduced delta because the LNA is switched on Receiver Block Diagram Figure 18 illustrates a simplified block diagram of the receiver. The diagram shows every major component from the antenna port to the I and Q baseband. Note: See the Schematics chapter for an RH-48 receiver schematic.
RH-48 Troubleshooting - RF CCS Technical Documentation Synthesizer Setup Use the following steps to set up the phone for Tx troubleshooting in Phoenix. 1 Open the Phone Control dialog box. Figure 19: Phone Control dialog box for Tx troubleshooting 2 Click the LOCAL button in the Phone State area to put the phone into Local Mode. 3 Use the following settings for the Band, Channel, and Mode fields on the RF Main Mode dialog box: • UHF: Use the Rx/Tx mode in Cell band.
RH-48 Troubleshooting - RF CCS Technical Documentation 4 Click the Set button. Note: Be sure that the “RF Main Mode set successfully...” message appears in the status bar. 5 Read register templates Jedi(0) bits 10 and 11 for the UHF and Tx VHF lock condition on the RF Register R/W dialog box. 6 Read register templates Yoda(0) bit 11 for the RX VHF lock condition.
RH-48 Troubleshooting - RF CCS Technical Documentation Use the following steps to manually tune the VCTCXO: 1 Open the Phone Control dialog box. 2 Click the LOCAL button in the Phone State area to put the phone into Local Mode.
RH-48 Troubleshooting - RF CCS Technical Documentation 6 Type 10, 13, 12, and 8 in the fields in the PIN # column. Figure 24: General I/O dialog box for VCTCXO tuning 7 Click the Get All button. 8 Change the value for Pin 8 in the Source column to GenIO Output. 9 Ensure that all of the pins have a value of H in the State column. (Click the L values to change them to H values.) 10 If using an HP4406 or a spectrum analyzer to measure the signal, set the center frequency to 836.
RH-48 Troubleshooting - RF CCS Technical Documentation 12 Adjust the AFC value to center the VCTCXO on the RF PDM dialog box. The tuning range is approximately +/- 10kHz. Figure 25: Manually adjusting the AFC to center VCTCXO 13 Adjust the AFC value so that the output signal is within +/- 100Hz. If you are using an HP4406 or a spectrum analyzer, narrow the span to 1kHz or less.
RH-48 Troubleshooting - RF CCS Technical Documentation VCTCXO Reference Clock Figure 26 shows the 19.2 MHz VCTCXO reference clock. Figure 26: (Top) PWB. (Bottom left) A zoomed view of the testing points on the 19.2 MHz VCTCXO reference clock. (Bottom right) A zoomed view of the 19.2 MHz VCTCXO reference clock with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 27 shows the synthesizer block diagram. Note: See the Schematics chapter for an RH-48 synthesizer schematic. Figure 27: Synthesizer block diagram UHF Synthesizer Following are possible causes for an incorrect UHF frequency: • Power supplies to Jedi PLL (N601) are missing or low (VR7) • Loop filter components are missing or incorrectly installed • Matching components to Jedi TxLO/PLL input are missing or incorrectly installed • 19.
RH-48 Troubleshooting - RF CCS Technical Documentation Figures 28 and 29 show the UHF synthesizer layout. Figure 28: (Top) PWB. (Bottom left) A zoomed view of the testing points on the UHF synthesizer layout. (Bottom right) A zoomed view of the UHF synthesizer layout with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 29: (Top) PWB. (Bottom left) A zoomed view of the Jedi LO/PLL input match components on the UHF synthesizer layout (Bottom right) A zoomed view of the Jedi LO/PLL input match components UHF synthesizer layout with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 30 shows the layout for the Rx VHF. Figure 30: (Top) PWB. (Bottom left) A zoomed view of the testing points on the Rx VHF section. (Bottom right) A zoomed view of the Rx VHF section with part numbers. Tx VHF Following are possible causes for an incorrect Tx VHF frequency: • Power supplies to the PLL portion of Jedi IC (N601) missing or low (VR5) • Loop filter or resonator components are missing or incorrectly installed • 19.
RH-48 Troubleshooting - RF CCS Technical Documentation Figure 31 shows the layout for the Tx VHF. Figure 31: (Top) PWB. (Bottom left) A zoomed view of the testing points on the Tx VHF section. (Bottom right) A zoomed view of the Tx VHF section with part numbers.
RH-48 Troubleshooting - RF CCS Technical Documentation Tuning Descriptions Tuning Title Description Troubleshooting Tx Detector This is one of the phone's self-tests which gives either a pass or fail result only. The phone transmits at several power levels and checks the ADC value of the power detector. The ADC value is measured first for a set of AGC values, then each AGC value is changed one at a time to make sure that the ADC changes as each AGC is changed individually.
RH-48 Troubleshooting - RF CCS Technical Documentation Tuning Title Description Troubleshooting VCTCXO Frequency The purpose of this tuning is to determine what the AFC DAC value needs to be in order to center the VCTCXO frequency. The transmitter is turned on and no Tx baseband modulation is provided. The carrier is then centered in frequency. This is done to the carrier after it has been mixed up to 836.52MHz, since it's easier to measure the tolerance of 1ppm at 836.52MHz than it is at 19.2MHz.
RH-48 Troubleshooting - RF CCS Technical Documentation Tuning Title Description Troubleshooting 5) If the carrier cannot be centered, check to see if you can adjust to 2.2v on pin 1 of G501. If you can, within the PDM range of +/- 150, then the circuitry that delivers the voltage is working correctly, and the VCTCXO has a problem. Troubleshoot it as described in the previous section. If you cannot adjust to 2.2v within the accepted range, then the AFC circuitry has a problem.
RH-48 Troubleshooting - RF CCS Technical Documentation Tuning Title Description Troubleshooting Tx Gain Comp This tuning ensures that the value of TxdBCtr correctly corresponds to the absolute Tx output power. On the mid channel, with TxdBCtr set to a specified value, G_Offset is adjusted so that the output power is -8dBm, and that value of G-Offset is recorded (which is an absolute value) in the next tuning. The output power in dBm is recorded in this tuning.
