Nokia NSB-9 Service Manual page 181

CCS Technical Documentation
Check VCTCXO
output signal at TP20
26 MHz
Check TX IQ signals
at TP21
Check TX modulator
output signal at TP24
836.6 MHz
Issue 1 04/03
Figure 1: Fault finding chart, TX850
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
3346.4 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
Troubleshooting Instructions
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:
1.1 VDC ± 200 mV
DMM
Change
Hagar ASIC
N600
Start baseband
troubleshooting (UEM)
NSB-9
DMM
DMM
Change
SHF VCO
G650
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