Rx Am Suppression (Gsm) - Nokia N72 Service Manual

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RF Troubleshooting and Tuning Guide
14. Go through all bands, and click Close to end the tuning.
Results

Rx AM suppression (GSM)

Context
Rx AM suppression is used to tune the AM suppression capabilities of the GSM receiver.
AM suppression is related to the ability of the receiver to operate when there is a disturbing AM modulated
signal near the received channel signal frequency.
RFIC has a tunable compensation circuit which has an effect on the AM suppression ability.
In Rx AM suppression, a continuous signal accompanied with an AM modulated signal 10 MHz above the
current channel is feed to the antenna. RFIC control word values are iterated until a minimum RSSI signal is
found.
Steps
1. Connect the GSM connector of the module jig to a signal generator.
Phoenix service software.
2. Start
3. Choose File→Scan Product.
4. From the drop-down menus, set Operating mode to Local, and select the GSM900 band.
5. Choose Tuning→GSM→Rx AM Suppression.
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