Issue 1 04/2005
COMPANY CONFIDENTIAL
45
Copyright © 2005 Nokia. All Rights Reserved.
RM-94
3 - Service Software and Tuning Instructions
Nokia Customer Care
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 test-
ers 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 cal-
ibration 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. For an error free initial
synchronization, the 26 MHz frequency of the reference oscillator must be accurate enough.
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
Helgo 8.6
