Nokia NSB-9 Service Manual page 184

NSB-9
Troubleshooting Instructions
Check VCTCXO
output signal at TP20
26 MHz
Check TX IQ signals
at TP21
Check TX modulator
output signal at TP22
1880 MHz
Page 10
Figure 2: Fault finding chart, TX1900
Check VCTCXO
supply voltage at TP3
2.78 VDC ± 3%
OSC
Check VCTCXO
control voltage at
TP13
1.1 VDC ± 200 mV
Change VCTCXO
G660
OSC
SA
Check SHF VCO
output signal at TP40
3760 MHz
Check Hagar ASIC
supply voltages at
TP4, TP5, TP6, TP8:
2.78 VDC ± 3%
TP10: 1.35 VDC ± 2%
TP1: 4.75 VDC ± 3.2%
Nokia Corporation
CCS Technical Documentation
Start baseband
troubleshooting (UEM)
DMM
DMM
Start baseband
troubleshooting (UEM)
Start baseband
troubleshooting (UEM)
SA
Check VCO supply
voltage at TP7:
2.78 VDC ± 3%
Check VCO control
voltage at TP41:
2.7 VDC ± 200 mV
DMM
Change
Hagar ASIC
N600
Start baseband
troubleshooting (UEM)
DMM
DMM
Change
SHF VCO
G650
Issue 1 04/03