Gsm Transmitter Activation - Nokia RM-779 Service Manual

Note: Never activate the GSM or WCDMA transmitter without a proper antenna load. Always connect
a 50 Ω load to the RF connector (antenna, RF measurement equipment or at least a 2 W dummy
load), otherwise the power amplifier (PA) may be damaged.

GSM transmitter activation

Steps
1. Set the phone to local mode.
2. Activate the RF controls tool in Phoenix ( Testing → GSM → RF Controls ).
3. Make settings as shown in the figure:
4. GSM transmitter is activated when Active Unit is set to "Tx". Nitro (N7509) supply voltages are on for
measurement purposes after this step is completed.
Optional step (not needed if GSM TX activation only required): Check the basic TX parameters (i.e. power,
5.
phase error, modulation and switching spectrum) manually, using a communication analyzer (for example
CMU–200). Change power level (in "RF Controls" tool) and make sure the power reading follows
accordingly.
Page 4 – 18 COMPANY CONFIDENTIAL
Copyright © 2011 Nokia. All rights reserved.
RM-779
Cellular RF troubleshooting
Issue 1