Dvga; Receiver Rf Test Point - Nokia 2608 Service Manual

RM-376
RF Troubleshooting
Cell Receiver Check DVGA and LNA offset value
LNA Range
Input RF level (dBm)
Reasonable offset value

Receiver RF test point

For the test points in below figure, an external signal source of –25 dBm was injected to the RF input. Set LNA
GAIN STATE = 0 .The signal was then traced throughout the receiver chains. A CMU200 call box is recommended.
(Open non-signaling mode, press the SG soft button, and then select CW.) Inject a continuous wave (CW) for
Cell (881.52MHz) at a fixed –25 dBm power level. Measurements were taken with the RF Probe. Signal levels
are approximate, and the accuracy may be +/- 2 dB or more depending on the probe position and grounding.
# Test Point
1 C1806.2
2 C1814.1
3 L1701.1
4 L1711.1
5 C1711.1
6 L1709.2, L1707.1 RX MIXER IN
Issue1

DVGA

-92.6
10~70
Description
RF Connector to FEM
FEM OUTPUT
LNA IN
RX SAW INPUT
RX SAW OUTPUT
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LNA1 LNA2
-81.8
80~152 160~277
LNA3
-53.8 -43.8
280~430
Value
-30dBm
-33dBm
-30dBm
-22dBm
-23dBm
-27dBm
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