Rap3G Faulty; Gsm Transmitter Phase Error Ok; Are Capacitors In Vinku Reg1 And Reg2 Lines In Place; Are Capacitors In Gsm Pa Power Supply Line In Place - Nokia 6680 RM-36 Service Manual

Appendix A: RF Troubleshooting
help go to the next step.
3.2.3.1.3.3 Replace Hinku (N7500) or Vinku (N7501) or both
3.2.3.1.4 Replace Hinku (N7500)
3.2.3.2 Replace Hinku (N7500)
• Also RAP3G can be faulty but it's not possible to replace this component

3.2.4 RAP3G faulty?

Not possible to replace!
•

3.3 GSM Transmitter phase error ok?

• GSM transmitter has to be active before measurements. Procedure is explained in section
"Transmitter troubleshooting". Change TX data type to "Random" in Phoenix.
• Measurement can be done with a GSM transmitter tester or other GSM communication tester.
Trigger to TX burst midamble should be used.
• Attach the phone to the product specific test jig and the RF-measurement device to the RF-coupler.
Coupler attenuation should be also taken into account during measurements.
• The RMS Phase error shall not be greater than 5° and the peak phase error not greater than 20°.
• If phase error is not as expected separate the phone into parts and place to the module jig (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).

3.3.1 Are capacitors in Vinku REG1 and REG2 lines in place?

C7554, C7555 and C7547 (GSM1800 and GSM1900: also C7552)
• Check that components are in place and solder joints are ok

3.3.2 Are capacitors in GSM PA power supply line in place?

C7569 and C7583
•
• Check that component is in place and solder joints are ok

3.3.3 Are TX-IQ signals ok?

• These current mode signals are not possible to measure, but are tested with self-tests. So if there
is no fail in 2.3 "ST_CDSP_TX_IQ_TEST" these signals should be ok. Otherwise Vinku (N7501) or
RAP3G (D2800) is faulty. Notice that it is not possible to replace RAP3G ASIC.

3.3.4 Is TX VCO signal level in the T7503 output high enough?

• GSM transmitter has to be active before TX VCO's output level can be measured. Procedure is
explained in section "Transmitter troubleshooting".
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