User Guide

RH-48
Troubleshooting - RF CCS Technical Documentation
Page 6 ©2003 Nokia Corporation Confidential Issue 1 11/2003
• The SID is correct and entered into the phone.
• The MIN and MDN are entered into the phone.
• The VCTCXO is centered as described in the VCTCXO tuning description on page 31.
• The transmitter and receiver are working properly in Local Mode.
Transmitter Troubleshooting
Low Tx Power
Use Phoenix to turn on the transmitter in local mode, and check the following:
1 Verify the current (0.7 - 1A for max power, mode, and channel dependent).
2 Use a microscope to visually inspect the PWB for proper placement, rotation, and
soldering of components.
3 Look for the presence of a Tx signal on the spectrum analyzer at the correct fre-
quency:
• If the signal is not on frequency, check in the 100 MHz span.
• If the signal is present but off frequency, check the synthesizer. Most likely, one
of the synthesizers is not locked, or the VCO has no output signal.
• If the signal is not present, or is present but low in amplitude, use the probing
tables to determine where in the chain the fault occurs.
4 Verify that the AGC PDMs are set for the desired Tx power as listed in the Tx AGC
Tuning table on page 12, and ensure that the AGC voltages are correct.
5 Check the LOs for proper frequency and amplitude.
6 Ensure that the power supplies to the transmitter have the correct voltage.