
NPD-4
Troubleshooting — RF
CCS Technical Documentation
Page 32
Nokia Corporation Confidential
Issue 1 02/2003
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Table 4: RF/Analog Probing for PCS transmitter
Probing point
Probing
location on
board
Measured power (dBm) using RF
probe, or gain/loss (dB)
What to check if RF power not
correct (soldering, shorts, DC
power applied if active, correct
voltage of DC signals, otherwise
replace)
Robin (N601)out =
PCS Balun (T603)
in
16a and 16b,
Figure 5
Easiest to probe on balun output as
per Table 1. Nominal loss through
Balun = 1 dB, but it will appear as
1-2 dB gain due to impedance. On
Robin output you may see ampli-
tude imbalance between 2 sides of
probing point 16 due to impedance
differences, (less in cell).
N601 (also check VR2, VR3, VR6,
VRIO, include check of AGCs as in
Table 5, check VREFRF02 as in
Table 5), T603, L609, L610, C624,
C647, L666, C646, L667, C660,
N602 (including check for 3.6v on
pins 7 and 9), D400
PCS Balun (T603)
out = Hornet
(N602) in
17, Figure 5
See Table 1.
T603, L609, L610, C624, C647,
L666, C646, L667, C660, N602
(including check for 3.6v on pins 7
and 9), D400
Hornet (N602) out
= PCS TX SAW
filter (Z601) in
18a for chan-
nels 25-599,
18b for chan-
nels 600-1175,
both Figure 5
Gain=14.5-17.5 dB through Hornet
N602 (including: ensure 3.6v on
pins 7 and 9; ensure PD_PCS high
as in Table 5; and check PCS_CTRL
as in Table 5 according to the
channel used), Z601, C611, C635,
C634, C627, C645, N605 (including
FILSEL1 and FILSEL2 as in Table 5)
PCS TX SAW filter
(Z601) out =
switch (N805) in
19a for chan-
nels 25-599,
19b for chan-
nels 600-1175,
both Figure 5
Loss=2-3.5 dB through filter
N602 (including: ensure 3.6v on
pins 7 and 9; ensure PD_PCS high
as in Table 5; and check PCS_CTRL
as in Table 5, according to the
channel used), Z601, C611, C635,
C634, C627, C645, N805 (including
FILSEL1 and FILSEL2 as in Table 5)
Switch (N805) out
= PCS PA (N802)
in
20, Figure 5
Loss=0.5 – 1.0 dB through switch
N805 (including FILSEL1 and
FILSEL2 as in Table 5), N802
(including check for 3.6v on Vbat),
C809, C814, C808
Table 3: DC probing for Cell/AMPS transmitter
Item to
check
Setting
DC probing
location on
board
DC Voltage
Items to check if voltage
incorrect