Nokia 500, Руководство по обслуживанию

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RF Testing selection does all the same measurements as RF Tuning , but does not perform any tunings.
RF Testing
is a safe way to check the basic cellular RF performance of the phone. The following test cases will
be performed (the complete set of measurements may differ depending on the data package content):
•
GSM SNR
• GSM RSSI
•
GSM / EDGE TX Power Level
• GSM Modulation & Switching spectrum
•
GSM EDGE EVM
•
GSM Burst Template
• GSM Phase Error
•
WCDMA RSSI
• WCDMA SNR
•
WCDMA TX Power Range
•
WCDMA TX Max Output Power
•
WCDMA ACP
•
WCDMA EVM
Troubleshooting with Testing And Tuning Tool
Context
If limit fails occur while RF tests are performed with Testing And Tuning Tool, the user has to be very careful
to understand the measurement results. Fails may occur because of many reasons:
1 RF attenuation between the phone and the communication tester is something else as expected by the
Testing And Tuning Tool
. Please check that cable, splitter and shield box selections are correct in the
Testing And Tuning Tool main window.
2 Test limits (specified in the product specific data package) are quite tight. Small limit violations do not
always mean that the tested product is broken, but the RF performance may not be as good as it should
be.
3 RX measurements (RSSI, SNR) may fail because of strong signals from base stations nearby. It is
recommended to always perform RF measurements in an RF-shielded environment (in an RF-shield box
or room).
4 The phone is really broken and needs more specific troubleshooting. Typical for these cases is that
RF
Testing
gives measurement results which are far from the test limits.
Manual transmitter (TX) testing with Phoenix
General instructions for transmitter (TX) activation
Please note the following before performing transmitter tests:
•
TX troubleshooting requires TX operation
•
Do not transmit on frequencies that are in use
•
The transmitter can be controlled in local mode for diagnostic purposes
• The most useful Phoenix tool for GSM transmitter testing is “RF Controls”, in WCDMA transmitter testing
the best tool is “TX Control”
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.
RM-750
Cellular RF troubleshooting
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