Nokia NSW-5 Series User Manual

NSW-5
Disassembly and Troubleshooting Instructions
PAMS Technical Documentation
Page 49
Issue 1 10/00
 Nokia Mobile Phones Ltd.
AMPS & TDMA800 UHF Synthesizers
1 GHz UHF VCO (G880) generates the first injection for RX (869...897
MHz) and the final injection for TX (824...849 MHz). The output frequency
of the module depends on the DC–control voltage supplied by the ERO-
TUS in line PD2.
1 GHz UHF Synth Troubleshooting
Is the frequency
locked?
N
What is VCO output
level ?, G820
P:>–5 dBm
Check local input
level of frontend
(N701, pin 1)
P:>–5 dBm
Change G820
Check C822
Check feedback
input level of
EROTUS
(at C821)
P:>–5 dBm
Check C821
and
Note!
Check all solderings,missing components
and supply voltage.
N
Y
N
Y
N
N
Check EROTUS (N750)
(SCLK):2.8V
pin 44 (SDATA):2.8V
(SENA1):2.8V
SENA is 0 during SCLK
and SDATA
N
Start BB
troubleshooting
NOTE!
Check EROTUS supply voltages
Y
Note!
The Oscillator is locked, when the
frequency and Vcnt are stable.
Frequency=985.23…..1010.16MHz
Vcnt=1….4V,C831

Nokia NSW-5 Series Specifications

General

Brand	Nokia
Model	NSW-5 Series
Category	Cell Phone
Language	English