Nokia Custome Care
Service Sofftware and Tuning Instructions
RH-37
Issue 1 07/04
Nokia Corporation
Page 47
Table 2: List of necessary tunings after replacement of RF key components and surrounding R/C/Ls
Semi-automatic calibrations and measurements - step by step: RX/TX and
GSM bands
RX tunings
The
RX calibration
has to be performed to determine gains at different gain settings in
the RF ASIC. The calibration must be done in
all three bands:
RX calibration requires an external RF signal generator. Most of the radio communication
testers like CMD 55 or CMU 200 can be used also as RF signal generators, generating
continuous RF signals (CW signal) with defined levels and frequencies.
Note: Depending on Firmware version, the CMU 200 can have problems generating a non-pulsed,
non-modulated CW signal.
RX calibration in the GSM900 band combines two alignments: AFC and AGC calibrations.
The calibration of GSM 1800 and GSM 1900 bands only determines the AGC values.
The
AFC calibration
detects an initial AFC value and an AFC slope coefficient. The AFC
calibration ensures the proper function of the initial synchronization (base station
search, before location update is done) when the phone has been set to Normal Mode.
Key Component Reference No.
Component Designation
T
x Power Level T
uning
T
x IQ T
uning
Rx Calibration
Rx Band F
ilter Resp. Calib.
Rx Channel Select F
ilter Calib.
Z7800
Antenna
Switch
Module
x
x
x
Z7802
SAW 1800 Rx
x
x
Z7801
SAW 1900 Rx
x
x
N7500
RF ASIC
(Helgo 8.5)
x
x
x
x
x
G7501
VCTCXO
x
G7500
VCO
x
N7700
TX-PA
x
x
Z7803
SAW900 Rx
x
x
Z7700
SAW900 Tx
x
Tunings/ Calibrations
