Gsm Transmitter Tunings; Tx Iq Tuning (Gsm) - Nokia MOBILE TERMINAL Service Manual

RM-356
RF troubleshooting
Ch. 810 / 1989.86771 MHz
Ch. 835 / 1994.86771 MHz
12. If the values are within the limits, click Next to continue to the next band.
Next actions
Repeat the steps 8 to 12 for GSM1800 and GSM1900.

GSM transmitter tunings

Tx IQ tuning (GSM)

Context
The Tx path branches to I and Q signals at RF I/Q modulator. Modulator and analog hardware located after
it cause unequal amplitude and phase disturbance to I and Q signal paths. Tx IQ tuning balances the I and Q
branches.
Tx IQ tuning must be performed for all GSM bands.
Steps
Phoenix service software.
1. Start
2. From the Operating mode drop-down menu, set mode to Local.
3. Choose Tuning→GSM→Tx IQ Tuning .
4. Select Mode: Automatic.
5. Select Band: GSM900 and click Start.
6. Click Next to start GSM1800 band TX IQ tuning.
Issue 1 COMPANY CONFIDENTIAL
Copyright © 2008 Nokia. All rights reserved.
Min Typ
-3 0
-6 -1
Max Unit
2 dB
2 dB
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