RM-94
Nokia Customer Care 3 - Service Software and Tuning Instructions
46
COMPANY CONFIDENTIAL
Issue 1 04/2005
Copyright © 2005 Nokia. All Rights Reserved.
Therefore, the previously calibrated AFC value is written to the DA converter and the corre-
sponding AFC voltage tunes the VCTCXO to the correct frequency.
The
AGC calibration
detects the gain values of the RX chain. The RF LNA can be switched
either on or off. The gain difference between on and off state is nominally 30dB and the base-
band gain which is controlled by 15 gain steps called in PHOENIX RSSI 0 to RSSI 14 each
having a graduation of 6 dB. The LNA is switched off at the steps RSSI 0 to RSSI 4.
AGC calibration detects the gain at the 3 gain steps RSSI 4, RSSI 5, and RSSI 7. All other steps
are calculated.
A value,
RF_TEMP
, which represents the RF hardware temperature, is determined during the
RX calibration. This temperature value is used by the DSP for RSSI reporting correction and
Tx temperature compensation in the Normal Mode of the phone. Dependent on the Phoenix
version it might be not displayed while calibrating.
The Rx calibration has to be done in a temperature of 25°C due to the detection and saving of
the RF_TEMP value.
The RX calibration is only valid if the results are within defined limits. For the latest specified
limits, please refer to the production limits of the FLALI and FINUI testers' documents.
If the results are not within these limit ranges, the receiver is faulty.
Rx calibration GSM900, GSM1800 and GSM1900
Open the window <Rx Calibration> in Phoenix Service Software as follows:
Select
Tuning
Alt-U
Rx
calibration
Alt-C
Phoenix automatically selects the low band.
Press <Start>
The window <Tuning step 1 of 3 – Rx Calibration with band …> pops up informing on power
level of the signal generator and frequency to be set. Do accordingly, after connecting the signal
generator to the antenna port of the test jig respectively to the phone. Compensate for external
RF cable and test jig losses.
If a radio communication tester (CMD 55, CMU 200, HP 8960, MT 8801) is used, assure that
<continuous mode> is switched on and <modulation> switched off.
Press <ok> and the window will close.
