Amps& Tdma800 Uhf Synthesizer - Nokia NSW-6 Series Disassembly & Troubleshooting Instructions

PAMS Technical Documentation
AMPS& TDMA800 UHF SYNTHESIZER
1 GHz UHF VCO (G880) generates the first injection for RX (869...897) and the final
injection for TX (824...849 MHz). The output frequency of the module depends on the
DC–control voltage supplied by EROTUS in line PD2.
Is the frequency
locked?
What is VCO output
levet ?, G800
P=–10–0 dBm
Check local input
level of frontend
(N701, pin 1)
P=–10–0 dBm
Check feedback
input level of
EROTUS
(at C825)
P=–10–0 dBm
Check EROTUS (N700)
(SCLK):2.8V
pin 55 (SDATA):2.8V
(SENA1):2.8V
SENA is 0 during SCLK
and SDATA
Issue 1 12/99
N
N
Change G880
Y
Check C827 &
N
L820
N
Y
N
Change C825
Start BB
troubleshooting
N
E Nokia Mobile Phones Ltd.
Disassembly & Troubleshooting
Note!
Frequency = 985.23...1010.2
Vcnt = 1.3...3.5 V , C826
Note!
Check all soldering & missing components
NSW-6
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