Nokia 7370, Руководство по обслуживанию

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RF tunings
Introduction to RF tunings
Important: Only perform RF tunings if:
• one or more of the RF components have been replaced
• flash Memory chip is replaced or corrupted.
RF calibration is always performed with the help of a product-specific module jig (MJ-62), never with an RF
coupler. Using an RF coupler in the calibration phase will cause a complete mistuning of the RF side.
Important: After RF component replacements, always use autotuning. Manual tunings are only
required in rare cases.
Cable and adapter losses
RF cables and adapters have some losses. They have to be taken in account when the phone is tuned. As all
the RF losses are frequency dependent, the user has to be very careful and understand the measurement
setup.
For RF attenuations of the module jig, please refer to the Service tools section.
Auto tuning for BB5.0
This phone can be tuned automatically.
Autotune is designed to align the phone's RF part easier and faster. It performs calibrations, tunings and
measurements of RX and TX. The results are displayed and logged in a result file, if initiated.
Hardware set up
Hardware requirements for auto tuning:
• PC (Windows 2000/NT) with GPIB card
• Power supply
• Product specific module jig
• Cables: XRF-1 (RF cable), USB cable, GBIP cable and DAU-9S
• Signal analyser (TX), signal generator (RX) and RF-splitter
or
one device including all.
Figure 45 Auto tuning concept with CMU200
RM-70
Nokia Customer Care RF Troubleshooting and Manual Tuning Guide
Page 7 –16 COMPANY CONFIDENTIAL Issue 1
Copyright © 2005 Nokia. All rights reserved.