User Guide

Other filter components are for sideband rejection.

The dividers are controlled via the RFBus. RFBusData is for the data, RFBusClk is a serial clock for the bus and

RFBusEna1X is a latch enable, which stores the new data into the dividers.

Figure 154 Synthesizer key components

Assumption

• No soldering or component failure for simple SMD components such as resistors, inductors and capacitors

• Failure in one particular operating GSM channel, whether Tx or Rx, in which the synthesizer is the cause of

the failure, causes failure in all other GSM channels in Tx/Rx.

Preparing for synthesizer troubleshooting

Steps

1. Place the phone (mechanics removed) on module jig.

2. Connect the module jig to the PC via a DAU-9P cable.

3. Connect the module jig to a power supply (4.2V).

4. Connect the RF output to a spectrum analyzer or another measurement instrument.

5. Use a 10dB attenuator at the input to spectrum analyzer to avoid damage.

6. Make sure the dongle is connected and start Phoenix.

7. In Phoenix, select File -> Open Product -> RM-51 (Nokia 3230) Product Menu.

8. Select Testing -> RF Controls.

9. In the toolbar: set Operating Mode -> Local.

10. Select Band -> GSM 1800.

11. Set Operation Mode -> Continuous.

12. Set Active Unit -> Rx.

RM-51

RF troubleshooting Nokia Customer Care

9238460 (Issue 1) Company Confidential Page 7–39