Nokia RM-57, Service Manual

Page: 183 / 391

Table of Contents
Introduction to RF troubleshooting .......................................................................................................................................... 7–5
RF key component placement ..................................................................................................................................................... 7–5
Fault finding test point locations ............................................................................................................................................... 7–7
Receiver troubleshooting ........................................................................................................................................................... 7–10
Introduction to Rx troubleshooting .................................................................................................................................. 7–10
GSM Rx chain activation for manual measurements / GSM RSSI measurement ................................................. 7–10
Transmitter troubleshooting .................................................................................................................................................... 7–11
General instructions for Tx troubleshooting .................................................................................................................. 7–11
Checking GSM and Bluetooth antenna functionality ................................................................................................... 7–13
RF tuning ......................................................................................................................................................................................... 7–14
Introduction to RF tunings ................................................................................................................................................... 7–14
RF autotuning ......................................................................................................................................................................... 7–14
RF manual tuning guide ....................................................................................................................................................... 7–18
Required manual tunings after component changes ........................................................................................... 7–18
RF channel filter calibration ........................................................................................................................................... 7–19
Temperature sensor calibration ................................................................................................................................. 7–19
Receiver tunings ................................................................................................................................................................ 7–20
Rx calibration .............................................................................................................................................................. 7–20
Rx band filter response compensation ............................................................................................................... 7–24
Rx AM suppression ..................................................................................................................................................... 7–29
Transmitter tunings ......................................................................................................................................................... 7–30
Tx IQ tuning ................................................................................................................................................................. 7–30
Tx power level tuning ............................................................................................................................................... 7–33
List of Tables
Table 13 RF channel filter calibration tuning limits .......................................................................................................... 7–19
Table 14 Temperature sensor calibration tuning limits .................................................................................................. 7–20
Table 15 RF tuning limits in Rx calibration ........................................................................................................................... 7–23
Table 16 RSSI level values .......................................................................................................................................................... 7–30
List of Figures
Figure 61 RF key component placement ................................................................................................................................. 7–6
Figure 62 Test point locations for spectrum analyzer ......................................................................................................... 7–7
Figure 63 Test points for oscilloscope - bottom .................................................................................................................... 7–8
Figure 64 Test points for oscilloscope - top ............................................................................................................................ 7–9
Figure 65 RSSI Reading window .............................................................................................................................................. 7–10
Figure 66 RF Controls window .................................................................................................................................................. 7–13
Figure 67 Feed and GND spots of the main antenna ......................................................................................................... 7–13
Figure 68 BT antenna .................................................................................................................................................................. 7–14
Figure 69 RF channel filter calibration typical values ....................................................................................................... 7–19
RM-57/58
RF Troubleshooting and Manual Tuning Guide
Nokia Customer Care
Issue 1 Company Confidential Page 7–3
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