Appendix A: RF Troubleshooting
Nokia Customer Care
Company Confidential
Copyright
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2005 Nokia. All rights reserved
A-71
4. DOES THE PHONE REGISTER TO THE NETWORK AND MAKE A CALL (WCDMA)?
•
Test against a WCDMA communication tester or real WCDMA network with a proper SIM.
4.1 WCDMA TX power and transmit frequency ok?
•
Attach the phone to the product specific test jig and a spectrum analyser to the RF-coupler.
Coupler attenuation should be also taken into account during measurements. This measurement
should be done in an RF shielded box.
•
Close the shield box hatch.
•
Set WCDMA TX ON. Procedure is explained in section “Transmitter troubleshooting”.
•
Spectrum analyser centre frequency should be set according the used TX channel (see section
“Frequency mappings”).
•
Spectrum analyser RBW = VBW = 10 MHz, Span
≤
2 MHz, sweep time 100 ms.
•
Test at power level 21 dBm
-
The output power should be +17 – +23 dBm, typical value 21 dBm.
•
Remember to select “Stop RF” in Phoenix before opening the shield box hatch.
•
If power is not as expected separate the phone into parts and place to the module jig. Connect a
spectrum analyser to the module jig WCDMA RF connector and measure TX power again (
Notice
that there are three antenna connectors in the module jig, one for GSM, one for WCDMA and one for
Bluetooth. Make sure that all connections are made to the correct RF-connector
).
-
TX power ok in the module jig: Antenna or antenna connection bad. Replace the antenna
-
TX power still wrong or no TX signal found at all: Continue troubleshooting
•
If TX signal is not found at all use wider span setting and check if the transmitter is transmitting
on wrong frequency. If signal is found to be on wrong frequency, see section, 4.1.3.
transmitter frequency correct?".
4.1.1 Does the WCDMA TX transmit RF-power at all?
•
If TX signal is not found at all use wider span setting and check if the transmitter is transmitting
on wrong frequency. If signal is found to be on wrong frequency, see section 4.1.3. "
transmitter frequency correct?
4.1.1.1 Is Vinku (N7501) transmitting RF-power at all?
•
WCDMA transmitter has to be active before Vinku’s output level can be measured. Procedure is
explained in section “Transmitter troubleshooting”.
•
Measurements can be done with a spectrum analyser and an RF probe. Spectrum analyser centre
frequency should be set according the used TX channel (see section “Frequency mappings”).
