RH-13
Troubleshooting
CCS Technical Documentation
Page 36
ã
Nokia Corporation
Issue 1 11/02
T
DMA800
Since there is same physical signal path for both analog (AMPS) and digital modes
(TDMA/GSM) in lower band there is no need for additional troubleshooting in digital
modes. If digital mode in lower band is not working properly start analog mode trouble-
shooting.
GSM850
Figure 18: Fault finding chart.
Apply signal to ext.
antenna connector
f= 881.46771 MHz
(ch 189)
unmodulate
level= -80 dBm
Check signal level
at RX I/Q J808,
J809, J818, J819
OK
GSM850 RX is
OK
Not OK
Check signal level
at diplexer Z908
input
Replace external
antenna connector
X900
Not OK
OK
Check signal level
at duplex filter
Z906 input
Replace diplexer
Z908
Not OK
OK
Check signal level
At LNA_a input
coil pad (L802)
Replace duplex
filter Z906
Not OK
OK