Rf Tunings; Introduction To Rf Tunings; Autotuning For Bb5 - Nokia RM-235 Service Manual

RM-235
RF troubleshooting

RF tunings

Introduction to RF tunings

Important:
• 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, never with an RF coupler.
Using an RF coupler in the calibration phase will cause a complete mistuning of the RF part.
Important:
required in rare cases.
Cable and adapter losses
RF cables and adapters have some losses. They have to be taken into account when the phone is tuned. As
all RF losses are frequency dependent, the user has to act very carefully and understand the measurement
setup.

Autotuning for BB5

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/XP) with GPIB card
• Power supply
• Product specific module jig
• Cables: XRS-6 (RF cable that requires an additional product-specific adapter cable), USB cable, GPIB cable
and DAU-9S
• 6dB attenuator (suitable to cover tuning frequency range) between CMU200 and Module jig (location is
close to the module jig). Ensure that the 6dB pad loss is added in the Jig losses.
• Signal analyser (TX), signal generator (RX) and RF-splitter
Issue 1
Only perform RF tunings if:
After RF component replacements, always use autotuning. Manual tunings are only
Figure 29 Auto tuning concept with CMU200
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or one device including all.
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