CCS Technical Documentation
Troubleshooting — RF
NPD-1
Issue 1 11/2002
Nokia Corporation Confidential
Page 37
VREFRF01
fixed
57, Figure 6
1.35 v
D200, C706, N701
Table 10: RF probing for PCS front end receiver
Probing point
Probing
location on
board
Probed absolute
power (dBm) or gain/
loss (dB)
Where to start checking if RF
power not correct (soldering,
shorts, DC power applied if
active, correct voltage of DC
signals, otherwise replace)
Diplexer (Z805)
out= PCS duplexer
(Z804) in.
23, Figure 7
Loss=0.5 dB through
diplexer
X800, L812, C801, Z805, Z804,
Z801, C752, L751, N750. (If all
these are ok and it passes con-
ducted test but fails radiated test,
then check the following: L802,
R823, L803, R824, X811, X810,
X814, L851)
PCS duplexer
(Z804) out= Alfred
(N750) LNA in
42, Figure 7
Loss=1-3.5 dB
through duplexer
Z804, Z801, Z805, C752, L751,
N750 (including check for proper
voltages on Alfred signaling as in
table 3c)
Alfred (N750) LNA
out= PCS RX saw
(Z750) in
43, Figure 7
Gain=12-14 dB for
high gain, Loss=-3 to
–5 dB for low gain,
use AGC status win-
dow to monitor gain
status
N750 and supporting components
(Also ensure BAND_SEL high as in
Table 9. Also IF_SEL low for CDMA
as in Table 9. Ensure GAIN_CTL
high if RX power is below the LNA
switch point), Z750
PCS RX saw
(Z750) out=Alfred
(N750) mixer in
44, Figure 7
Loss=1-4 dB
Z750, N750 and supporting com-
ponents (including check for proper
voltages on Alfred signaling as in
Table 9)
Table 9: DC probing for receiver
Item to check
Setting
DC probing
location on
board
DC voltage
Items to check if voltage
incorrect