Wcdma Tx Synthesizer Troubleshooting - Nokia 7600 Troubleshooting Manual

CCS Technical Documentation

WCDMA Tx Synthesizer Troubleshooting

Phoenix Settings:
Tx Contol (WCDMA)
Algorithm mode
Start Level = 0dBm
Channel= 9750 (1950MHz)
Click SEND
Probe VCO o/p
3900Mhz
Span 1MHz
RF Level= -17dBm
No
Yes
VCO o/p signal
<-17dBm?
No
Check o/p signal on 1GHz
Span. Signal found on
correct frequency?
No
Yes
Check with meter VCO
control voltage R914=
0V?
No
VCO control
Voltage >4V
Yes
Replace
VCO
Issue 1 (11/2003)
Company Confidential
Yes
Synth
OK
Check balun output
& VCO solder joints
OK?
Yes
Replace
VCO
Yes
Yes
Check
Vcc= 2.8v
ExtReg1
No
Baseband
Troubleshooting
Check VCO loop
filter components
OK?
No
Replace faulty
components
Copyright  2003 Nokia Corporation
Company Confidential
No
Replace faulty
components
Replace
VCO
Yes
Check synth serial
interface on Tex
Yes
Replace
VCO
NMM-3
6-Troubleshooting
No
Tex
Troubleshooting
Page 6-27