
NPM-10
Troubleshooting Instructions RF
CCS Technical Documentation
Page 26
Nokia Corporation Confidential
Issue 1 03/2003
Troubleshooting the Modulation
The following plots show different situations of TX IQ measurements. Depending on the
time the modulation may cause the signal to look differently.
Figure 19: TX I/Q waveforms
I/Q signals look almost the same regardless if modulation is by "1" or by "0". There is no
significant difference between TXIP and TXIM. The same is valid for TXQP and TXQM.
General instructions for PCS TX troubleshooting
Apply an RF cable to the RF connector to allow the transmitted signal act as normal. The
RF cable should be connected to measurement equipment or to at least a 10-dB attenu-
ator, otherwise the PA may be damaged.
Start Phoenix-Service-Software and:
Establish a connection to the phone e.g. FBUS.
Select File
Pink trace: TXQP Blue trace: TXIP - All 1
Pink trace: TXQP Bluetrace: TXIP - Random
Pink trace: TXQP Blue trace: TXIP - All 1
(
Zoom In)
Pink trace: TXQP Blu etrace: TXIP - Random ( Zoom In)