User Guide

Nokia Customer Care RF Description and Troubleshooting

6255/6255i/6256/6256i (RM-19)

Transmitter Troubleshooting Setup

Use the following sets of procedures to troubleshoot the transmitter using Phoenix. Due

to the compact layout of the mobile terminal, some of the major test points are not

accessible without destroying the shield frames and the EL lamp. For example, duplexers/

diplexer/couplers test points are blocked by the test jig, the PA test points are

underneath the shield frame, and the BBIQ points are underneath the EL lamp.

To minimize effort, check the following in order:

1. Tx power at the RF connector.

2. All Tx DC points.

3. All soldering jig points for the whole Tx chain.

4. UHF LO presence:

• If the UHF LO is present, check the N7000 output.

• If the UHF LO is not present, it is a synthesizer problem.

5. If there is no N7000 output:

a. Change the N7000.

b. If the problem persists, reflow the duplexers, diplexer, and couplers.

c. If the problem persists, change the PA.

6. If there are several failed mobile terminals with the same symptoms, it may be

necessary to break one to determine the cause.

Use the following sections to set up troubleshooting in Phoenix according to the band

you are using:

• "AMPS Tx Setup" on page 15

• "Cell Tx Setup" on page 18

• "PCS Setup" on page 20

AMPS Tx Setup

Use the following procedures to prepare for AMPS Tx troubleshooting using Phoenix.

1. Connect the RF test connector to a spectrum analyzer.

2. Connect the mobile terminal to the PC via a test jig. (The bottom connector is a

USB port.)

3. Connect a power supply to the mobile terminal.

4. Open the Troubleshooting menu, and click Phone Control.

The Phone Control dialog box appears.