– 9-1 –
9.1. Introduction
9.2. Carrier Power Calibration
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General Information
The following procedure MUST be performed after replacement or repair of the PCB. Failure to do so may result in incorrect
operation of the telephone.
The following adjustment MUST be made to the complete unit using the appropriate Repair Jig.
The applied voltage should be a constant 3.7 V with a current limit of 2.5 A.
There are four distinct calibration procedures to adjust RF performance, These procedure are : Carrier Power calibration.
RSSI also
To ensure that the phone is within set SAR margina after Peak Power Calibration has been performed, a power mater that is
accurate to 0.2 dB MUST be used . The output power of the phone can be influenced by the RF/Logic shield covers, therefore
all power calibration procedures MUST be performed with the shield frames and covers fitted.
IF ANY OF THE RF OR LOGIC SHIELDS ARE REMOVED FROM THE PCB AT ANY TIME, THEY MUST BE REPLACED
WITH NEW ITEMS, ONCE REMOVED, THE SHIELDS MUST NOT REUSED.
Tx Calibration can be performed manually Manual Calibration is used to adjust or verify each calibration channel in turn.
To minimise the variation of Tx power with frequency due to component tolerance, each GSM band is split into sub-bands,
which are calibrated separately. The calibration bands and channels used are as follows.
9. CALIBRATION PROCEDURE
Band
Segment
Calibration Channel
0
12
1
38
EGSM 900
2
112
3
975
0
556
1
698
GSM 1800
2
750
3
842
0
512
1
624
PCS 1900
2
699
3
773
