Phoenix Tuning; Rf Tuning After Repairs; Rx Calibration (Incl. Vcxo Calibration) - Nokia NEM-4 Series Troubleshooting Instructions

CCS Technical Documentation

Phoenix tuning

Before any tuning the phone should be synchronized with the PC.
Connect the phone to a PC with DAU-9P cable and dongle and follow the following
instructions:
Provide the phone with power supply
Start Phoenix Service Software and open FBUS connection
Select
Wait until phone information is shown in the lower right corner of the screen.

RF tuning after repairs

Different repairs require different tuning. In general it is necessary to determine in which
section the repair was done to select which tunings to perform. To determine if RF tuning
is necessary after repair it is important that the functionality of the repaired circuit is
understood well.
• In general repairs in the TX part will require "TX Power Level Tuning" and "TX IQ
Tuning".
• In general repairs in the RX part or PLL part always require "RX Calibration", "Rx
Band Filter Response Calibration".
• If Mjoelner is changed all calibrations have to be done.
Other parts interfacing to TX, RX or PLL might require tuning, but common sense should
be used, e.g. if a component that has no influence on RF performance has been changed,
e.g. the microphone, on/off key, mechanical parts or similar, there is no need to do any RF
tuning.

RX Calibration (incl. VCXO Calibration)

The "RX calibration" is used to determine gain at different gain-settings for front-end
and Mjoelner and needs to be done in all three bands. The procedure begins with EGSM
and continues with GSM1800 and GSM1900.
RX-calibration requires an external signal generator.
RX-calibration in EGSM900 combines two tunings, VCXO-calibration and AGC-calibra-
tion:
Calibration of GSM1800 and GSM1900 band only determines AGC values.
The VCXO-calibration finds out a calibration value for VCXO control, an AFC initial
value and 3 AFC-slope coefficients.
Issue 1 09/2003
Company Confidential
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Copyright  2003 Nokia Corporation.
Company Confidential
NEM-4
RF Troubleshooting
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