Nokia 7600 - WCDMA Rx Synthesizer Troubleshooting

NMM-3 Company Confidential
6-Troubleshooting CCS Technical Documentation
Page 6-26 Copyright  2003 Nokia Corporation Issue 1 (11/2003)
Company Confidential
WCDMA Rx Synthesizer Troubleshooting
Replace
VCO
Synth
OK
Probe VCO output
4280MHz
Span 1MHz
RF Level= -17dBm
V
CO o/p signal
<-17dBm?
Check output signal on
1GHz Span. Signal found
on correct frequency?
Check with meter VCO
control voltage R802=
0V?
V
CO control
voltage >4V
Check balun output
& VCO solder joints
OK?
Replace
VCO
Check VCO
V
cc= 2.8v
VR6
Check VCO loop
filter components
OK?
Replace faulty
components
Check synth serial
interface on Rex
Rex
Troubleshooting
Replace faulty
components
Replace
VCO
Replace
VCO
Y
es
Y
es
Y
es
Y
es
Y
es
No
Y
es
Y
es
No
No
No
No
No
No
No
Y
es
Y
es
Phoenix Settings:
Rx Contol (WCDMA)
AGC mode = Manual
AFC algorithm= Off
Channel= 10700 (2140MHz)
Click SEND
Baseband
Troubleshooting
Y
es