Nokia 9000i, Service Manual

Page: 235 / 434

After Sales
Technical Documentation
RAE/RAK–1N
Service Software
Page 7– 77
Amendment 1 04/97
Tuning Procedure for GSM units
Carry out this procedure in the order as shown.
1. RSSI Reference Signal Level Storage
Reference value for the received signal strength meter are program tuned.
RSSI reference signal level programming:
– Start the service software and go to ”Main” menu.
– Select ”Phone mode” and select local mode with <Enter> key.
– Select ”Testing and Adjustments” menu and press <Enter>.
– Select ”Adjustments” menu and press <Enter>.
– Connect RF generator to antenna connector at 947.06771 MHz.
– Adjust signal generator level to –80 dBm + cable attenuation.
– Select ”RSSI Calibration” and press <Enter>.
– Adjust signal generator level to –50 dBm + cable attenuation.
(
see note below)
– Press <Enter>.
– DAC values should be in first row (0 dB) 450 – 700 and
last row (57 dB) 750 – 1000
– Press <Esc> key.
– Store the value to the EEPROM with <Y> key.
2. AFC Diagram Storage
This tuning is used to calibrate the automatic frequency control range.
AFC tuning:
– Set RF generator frequency 947.06771 MHz at level –45 dBm.
– Select adjustments menu option ”AFC Diagram” and press <Enter>
– Check that ” Cont mode channel” is 60
– The measurement result should be;
•
Low over –22 kHz (< –8 kHz)
•
Middle
±
1.5 kHz
•
High below +22 kHz (> 8 kHz)
– Press <Esc> key and store with <Y> key.
Note: Always take the target tuning value from the actual monitor screen as the value
can vary according to which CMT software version is used.