Nokia 3500 classic RM-272, Service Manual

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Table of Contents
Introduction to RF troubleshooting ..................................................................................................................... 4–5
RF key components ................................................................................................................................................ 4–6
BOM1 versus BOM3 ................................................................................................................................................. 4–6
Receiver troubleshooting ...................................................................................................................................... 4–9
Introduction to RX troubleshooting ................................................................................................................ 4–9
General instructions for RX troubleshooting .................................................................................................. 4–9
Receiver (RX) troubleshooting ...................................................................................................................... 4–11
GSM Rx chain activation for manual measurements / GSM RSSI measurement ....................................... 4–13
Transmitter troubleshooting ............................................................................................................................. 4–14
General instructions for TX troubleshooting ............................................................................................... 4–14
Transceiver (TX) troubleshooting ................................................................................................................. 4–17
Checking antenna functionality .................................................................................................................... 4–17
Synthesizer troubleshooting .............................................................................................................................. 4–21
RF tunings ............................................................................................................................................................ 4–22
Introduction to RF tunings ............................................................................................................................ 4–22
Auto tuning for BB5.0 .................................................................................................................................... 4–22
System mode independent manual tunings .................................................................................................... 4–23
RF channel filter calibration .......................................................................................................................... 4–23
PA (power amplifier) detection .................................................................................................................... 4–24
GSM receiver tunings ........................................................................................................................................... 4–24
Rx calibration (GSM) ....................................................................................................................................... 4–24
Rx band filter response compensation (GSM) .............................................................................................. 4–27
GSM transmitter tunings ..................................................................................................................................... 4–30
Tx IQ tuning (GSM) .......................................................................................................................................... 4–30
Tx power level tuning (GSM) ......................................................................................................................... 4–32
List of Tables
Table 9 Rf channel filter calibration tuning limits ........................................................................................... 4–23
Table 10 RF tuning limits in Rx calibration ....................................................................................................... 4–26
List of Figures
Figure 17 RF key components, bottom side main board ................................................................................... 4–6
Figure 18 RF block .................................................................................................................................................. 4–8
Figure 19 The visual differences between BOM1 and BOM3 .............................................................................. 4–9
Figure 20 RF Controls window ........................................................................................................................... 4–11
Figure 21 RSSI Reading window ........................................................................................................................ 4–14
Figure 22 RF Controls window ........................................................................................................................... 4–16
Figure 23 Location of the GSM and BT antenna C-clips on the PWB ............................................................... 4–18
Figure 24 GSM and BT antenna contact pads on the antenna module .......................................................... 4–19
Figure 25 Antenna C-clips on the PWB .............................................................................................................. 4–20
Figure 26 Auto tuning concept with CMU200 ................................................................................................... 4–22
Figure 27 Rf channel filter calibration typical values ...................................................................................... 4–23
RM-272; RM-273
RF Troubleshooting and Manual Tuning Guide
Issue 1 COMPANY CONFIDENTIAL Page 4 –3
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