Nokia RH-10 Series Troubleshooting Manual page 27

CCS Technical Documentation
Probing
Probing point location on
the board
Alfred (N750) 36, Figure 2
mixer out =
AMPS RX IF
saw (Z752) in
AMPS RX IF 37, Figure 2
filter (Z752)
out = Batman
(N701) in
Batman (N701) 38, Figure 3
out = UEM
(D200) in
VHF LO at 39, Figure 2
256.2 MHz
Item to check Setting
RX IF AGC See PDM set-
tings
GAIN_CTL High = LNA
high gain
Low = LNA low
gain
IF_SEL High = AMPS
Low = CDMA
Issue 1 09/2002
Table 6: RF Probing for AMPS back-end Receiver
Probed Absolute Power (dBm) or
gain/loss (dB)
This point not 50 ohms. Will meas-
ure approx. -28 dBm for -52 dBm
input and RX AGC PDM = 225
This point not 50 ohms. Will meas-
ure approx -46 dBm for -52 dBm
input and RX AGC PDM = 225
RSSI most useful
Table 7: DC Probing for Receiver
DC probing
location on board
40, Figure 3
55, Figure 2
57, Figure 2
Nokia Corporation
What to check if RF power not
correct (soldering, shorts, DC
power applied if active, correct
voltage of DC signals, otherwise
replace)
N750. IF_SEL low for CDMA and
high for AMPS. R722, C750, L771,
R723, C756, L770, L757, C758,
L755, C769, C766, C784, L764,
C781, Z752
Z752, L765, C777, L766, C778,
L768, L767, C779, N701 (VR5, VR7,
VIO)
N701 (VR5, VR7, VIO, ensure 1.35v
on VREFRF01; also check
RX_IF_AGC), R706, C704, R705,
R704, V701, C716, L701, C702,
C715, R702, C714, R703, C701
N701, C701, C714, R703, R702,
C715, R704, V701, C716, L701,
C702, R705, C706
Items to check if voltage
DC voltage
incorrect
See typical volt- D400, R436, C428, C435, N701
ages
High = 2.4v min N701, N750, R721, C753
Low = 0.3v max
1.35v D200, C706, N701
Confidential
RH-10
Troubleshooting
Page 27