Nokia RM-42 Service Manual
Also see for RM-42: Service manual
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | |
Appendix A: RF Troubleshooting Nokia Customer CareCompany ConfidentialCopyright © 2005 Nokia. All rights reservedA-553.2.2.6.1 VXO-voltage ok? (=Vdig).• Measurement can be done with an oscilloscope and a probe• Connect the probe to C7560 (or C7526, C7513)• VXO-voltage should be about 2.5 V3.2.2.6.1.1 C7560, C7513, C7526 and C2214 ok?• Check that components are in place and solder joints are ok• Disconnect the power supply from the phone and use an ohmmeter to find out if the VXO-line isshort-circuited to the ground. If short-circuit is found replace C7560, C7513, C7526 and C2214. Ifreplacing does not help then go to the next steps.3.2.2.6.1.2 Replace Retu3.2.2.6.1.3 Replace Hinku (N7500) or Vinku (N7501) or VCTCXO (G7501) or all three components3.2.2.6.2 BB AFC-voltage ok?• Measurement can be done with an oscilloscope and a probe• Connect the probe to R7509 (or C7533)• AFC-voltage may vary between 0.1 - 2.3 V. Typical value is 1.2 V. Phoenix “RF Controls” tool can beused to change the AFC value. Voltage level should be about 0.1 V with AFC value -1024 and about2.3 V with AFC value 1023.3.2.2.6.2.1 Low pass filter components R7509 and C7533 ok?• Check that components are in place and solder joints are ok• Disconnect the power supply from the phone and check R7509 resistance value with anohmmeter.• Use an ohmmeter to find out also if the AFC-line is short-circuited to the ground. If short-circuit isfound replace C7533. If this does not help then go to the next steps.3.2.2.6.2.2 VCTCXO ok?• Remove R7509. If AFC-voltage is correct after removing then replace faulty VCTCXO G7501 andsolder R7509 (new component) back to the PWB3.2.2.6.2.3 Replace Retu3.2.2.6.3 Replace VCTCXO G75013.2.2.7 Is there RF power in the RX VCO output at all?• GSM receiver has to be active before RX VCO’s output frequency and output level can be measured.Procedure is explained in section “GSM RX chain activation for manual measurements”.• Measurements can be done with a spectrum analyser and an RF probe. Spectrum analyser centre |
Related manuals for Nokia RM-42
This manual is suitable for:
manualsdatabase
Your AI-powered manual search engine