2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Transmitter Troubleshooting Low Tx Power Use Phoenix to turn on the transmitter in Local Mode, and check the following: • Verify the current (0.7 - 1A for max power, mode, and channel dependent).
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2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care 2. Click the LOCAL button in the Phone State area to put the mobile terminal into Local Mode. 3. Select the following values on the RF Main Mode dialog box: Band = Cell (CDMA) •...
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting 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.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 7: RF PDM dialog box for Tx troubleshooting 14. Ensure that the Phone Tx Pout = +25 dBm and the current = 770-860 mA. Cell Transmitter Path Table 1 indicates the test points (see...
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Table 1: Cell Transmitter Test Points (Continued) Typical Typical Test Value/ Value Part* Function Comments Point Frequency Frequency HP85024A Prod Probe C636L, C624T, 2.7 V dc Mixer, driver, and IF supply from...
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2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 8 shows each test point for the N601 TXIC section from Table 1, “Cell Transmitter Test Points,” on page 8. Always attach a 20 dB pad (11881-60001) when probing with an HP85024A high-frequency probe.
2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Figure 9 shows each testing point for the PA section from Table 1, “Cell Transmitter Test Points,” on page 8. Always attach a 20 dB pad (11881-60001) when probing with an HP85024A high frequency probe.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Table 2: Tx AGC Tuning Steps (Continued) Tx Tuning Tx AGC Target High AGC Step PDM Value Power Limit Limit Tx AGC (6) Tx AGC (7)* -280* *Not an actual FlaLi tuning PDM. The PDM produces approximately 25 dBm at the antenna connector.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Table 6: PMIC Measurements Label Test Point Units Depends On Comments Pin 1 IC enable = GenIO 10 Pin 2 Control 0 = GenIO 12 Pin 3 Control 1 = GenIO 13 Pin 5 0.75 - 4...
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Table 7: Good Mobile Terminal PMIC Resistances (Continued) Resistance 115 k 60 k 1.3 M 1.18 M Cell IF/RF AGC and PA Control Table 8, “Cell CDMA Channel 384 (Skyworks PA),” on page...
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Table 8: Cell CDMA Channel 384 (Skyworks PA) Tx RF AGC Tx IF AGC N601 Po PA Gain Step PA Vcc Conn RF Typical Test Typical Test Typical Test Typical Test...
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Cell Power Detector The following tables illustrate the measurements required for troubleshooting the cell power detector. Table 9: Cell Power Setup Mode Band Chnn Local CELL Input Chnn Tx Freq Rx Freq 836.52...
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Tx System Block Diagram See the Schematics chapter for a 2118 transmitter schematic. Antenna Antenna Antenna Antenna RF VGA Bandpass PWR Amplifier (RF AGC PDM) Duplexer Duplexer Duplexer Duplexer BB I LPF...
2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Receiver Troubleshooting Rx IF Use Phoenix to perform the following steps for troubleshooting the receiver. Together with the VCO frequency and level verification, this test should be the first test for a non- working receiver.
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2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 12: RF Main Mode dialog box for Rx IF troubleshooting 5. Click Set. Note: Be sure that the “RF Main Mode set successfully” message appears in the status bar. 6. Use a spectrum analyzer to test TP3 (I+,I-, Q+, Q-). Set the S.A to 300 KHz center frequency, 200 KHz SPAN, and +10 dBm reference level.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Table 13: Rx IF Troubleshooting (Continued) Typical Typical Value/ Value Step # Part Function Comments Frequency Frequency HP85024A Prod Probe I+, I-, Q+, Q- I/Q outputs 300KHz tone -69/-84 dBm Baseband differential...
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2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 13 shows each test point as listed in Table 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.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting shows an alternate part orientation. Notice that Pin 1 is rotated 180 degrees Figure 14 compared to the first filter as shown in Figure 13 on page 22. All test points and values are the same.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care 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. Figure 15: Phone Control dialog box for switching the Rx gain state 2.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting 5. Connect a signal generator in CW mode (881.52 MHz, -25 dBm) to the RF connector. If you do not have a generator, use the Call Box Amps Mode RF Generator, Channel 384, -25 dBm and set the FM modulation to 100 Hz, deviation 400 Hz.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care 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. See Figure 18 on page for an illustration of the test points.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Antennae Connector (top side) Figure 18: (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.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care 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. Table 15: Rx RF AGC PDM vs. AGC Voltage...
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Receiver Block Diagram See the Schematics chapter for a 2118 receiver schematic. CDMA I/Q Down LNA SW Control BB Filter Converter CELL IF SAW BB AMP To BB CDMA BB Filters...
2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Synthesizer Troubleshooting Faulty synthesizers can cause both Rx and Tx failures during tuning, in addition to the VCTCXO tuning. The following synthesizers are incorporated into the mobile terminal: • UHF (cell) PLL inside N601 IC •...
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2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 21: RF Main Mode dialog box for synthesizer troubleshooting 4. Click Set. Note: Be sure that the “RF Main Mode set successfully” message appears in the status bar. 5. Read register templates N601(0) bits 10 and 11 for the UHF and Tx VHF lock condition on the RF Register R/W dialog box.
2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting VCTCXO Tuning The VCTCXO can be manually tuned to verify failed tuned mobile terminals, or to verify if a mobile terminal cannot make a call. This can be done with the mobile terminal in Local Mode and generating a CW signal.
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2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 24: RF Main Mode dialog box for VCTCXO troubleshooting 4. Do not use CDMA control to turn on Rho. 5. Open the BB General I/O dialog box to set the CW signal.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting 10. The next step depends on the type of measurement equipment you are using: • HP4406 or a spectrum analyzer: Set the center frequency to 836.52MHz and the span to 2MHz. Also, establish a marker at 836.52MHz.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care VCTCXO Reference Clock Figure 27 shows the 19.2 MHz VCTCXO reference clock. To PLL Figure 27: (Top) PWB. (Bottom left) A zoomed view of the testing points on the 19.2 MHz VCTCXO reference clock.
2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Synthesizer Block Diagram See the Schematics chapter for the synthesizer schematic. CELL:457.2MHz CELL:457.2MHz JEDI JEDI counter counter counter counter 367.2MHz 367.2MHz 19.2MHz 19.2MHz VCTCXO VCTCXO CELLl Band UHF VCO CELLl Band UHF VCO...
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care UHF Synthesizer Following are possible causes for an incorrect UHF frequency: • Orientation of N601 • Power supplies to N601 PLL are missing or low (VR7) • Loop filter components are missing or incorrectly installed •...
2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting LO PLL Figure 30: (Top) PWB. (Bottom left) A zoomed view of the N601 LO/PLL input match components on the UHF synthesizer layout (Bottom right) A zoomed view of the N601 LO/PLL input match components UHF synthesizer layout with part numbers.
2118 (RH-77) RF Description and Troubleshooting Nokia Customer Care Figure 31 shows the layout for the Rx VHF. IC with Figure 31: (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.
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2118 (RH-77) Nokia Customer Care RF Description and Troubleshooting Figure 32 shows the layout for the Tx VHF. IC with Figure 32: (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.