Appendix D: Calibration Of The Da-17/Jxs-2 Jig, Autotuning And Bt Testing; Requirements; Calibration Problems; Active Calibration: Basic Idea - Nokia RH-47 Series Rf Description And Troubleshooting

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APPENDIX D: Calibration of the DA-17/JXS-2 jig, Autotun-
ing and BT Testing

Requirements

• U.S. AMS requirement is to align/check the phone completely assembled (in addi-
tion to the alignment in the MJ-21 repair jig which is still possible).
• RF couplers must be used because there is no RF connector on RH-47.
• DUT must be placed in a shielded box (JXS-2) to achieve accuracy and in order to
avoid external interference.
• First Symbian OS phone to support "RF autotuning".
• Normal to Local mode switching must be done manually as Symbian OS does not
support SW switching.

Calibration Problems

• PA (Hitachi PF 08130B-TB) O/P power is very sensitive to LOAD variations.
• GSM Dual band antenna match is only -5 dB on GSM850 TX band.
• Battery BL-6C is part of the antenna (GSM850) – but in the DA-17 jig, the bat-
tery is removed -> antenna resonance is shifted!
• Coupler is self-resonant and must be very close to the GSM antenna -> Further
resonance shift of GSM antenna.

Active calibration: basic idea

• DA-17/JXS-2 system is seen as a "black box".
• Calibration of the "black box" can be done with any functional phone sample and
MJ-21 repair jig.
• Once the calibration has been done, no changes inside the black box are allowed
(except removing and fitting the phone).
• All calibration data from the black box is based on conducted measurement with
MJ-21.
• The best accuracy is achieved for the highest TX power level (PCL0 / PCL5).

Calibration procedure setup MJ-21

The initial setup is shown below. The phone is disassembled and the engine PWB is
Issue 1 05/04
Company Confidential
=> very careful "active calibration" method is needed
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7 - RF Description and Troubleshooting
RH-47
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