Receiver Troubleshooting; Introduction To Receiver (Rx) Troubleshooting; Gsm Rx Chain Activation For Manual Measurements/Gsm Rssi Measurement - Nokia RM-721 Service Manual

RM-721; RM-722
RF Troubleshooting
If the phone is dead and you cannot perform the self tests, go to
Chapter 3, BB Troubleshooting and Manual Tuning Guide.
Note: Self tests are recommended to be made when phone is in jig and a 50Ω load connected to
the RF connector. Otherwise power tests may fail depending on antenna load.
Troubleshooting flow

Receiver troubleshooting

Introduction to receiver (RX) troubleshooting

RX can be tested by making a phone call or in local mode. For the local mode testing, use Phoenix service
software.
The main RX troubleshooting measurement is RSSI reading. This test measures the signal strength of the
received signal. For GSM RSSI measurements, see section
GSM RSSI measurement (page 4–7 )
measurement (page 4–11 )

GSM RX chain activation for manual measurements/GSM RSSI measurement

Prerequisites
Make the following settings in signal generator and Phoenix service software:
Setting
Phoenix Channel
Signal generator
to antenna
connector
Issue 1
. For a similar test in WCDMA mode, see section
.
GSM850
190
881.46771MHz
(67.71kHz offset)
at -60dBm
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Copyright © 2011 Nokia. All rights reserved.
Dead or jammed device troubleshooting in
GSM RX chain activation for manual measurements/
GSM900
37
942.46771MHz
(67.71kHz offset)
at -60dBm
WCDMA RSSI
GSM1800
700
1842.86771MHz
(67.71kHz offset)
at -60dBm
GSM1900
661
1960.06771MHz
(67.71kHz offset)
at -60dBm
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