Receiver Troubleshooting; Introduction To Rx Troubleshooting - Nokia 6680 RM-36 Service Manual

RM-36
RF Troubleshooting and Manual Tuning Guide Nokia Customer Care
Figure 67 Test points for oscilloscope - top

Receiver troubleshooting

Introduction to Rx troubleshooting

Rx can be tested by making a phone call or in the local mode. For the local mode testing, use Phoenix service
software.
The main Rx troubleshooting measurement is RSSI measurement. This test measures the signal strength of the
received signal. I and Q branches can be measured separately. For GSM RSSI measurement, see GSM Rx chain
activation for manual measurements / GSM RSSI measurement (Page 7–10), and for the same measurement
in WCDMA, see WCDMA RSSI measurement (Page 7–11).
In GSM, the input signal can be either a real GSM signal or a CW signal that is 67.771kHz up from the carrier
frequency.
For service tool usage instructions, refer to section Service Tools and Service Concepts.
See Also
• WCDMA Rx chain activation for manual measurement (Page 7–10)
Issue 1 Company Confidential Page 7–9
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