User Guide

2118 (RH-77)
RF Description and Troubleshooting Nokia Customer Care
Page 8 ©2005 Nokia Corporation Company Confidential Issue 01 04/2005
Figure 7: RF PDM dialog box for Tx troubleshooting
14. Ensure that the Phone Tx Pout = +25 dBm and the current = 770-860 mA.
Cell Transmitter Path
Table 1 indicates the test points (see Figure 8) to probe when troubleshooting the cell
transmitter path. It is recommended that you follow the steps in order. An HP high
frequency probe was used to make the frequency and output power measurements
Table 1: Cell Transmitter Test Points
Test
Point
Part* Function
Typical
Value/
Frequency
HP85024A
Typical
Value
Frequency
Prod Probe
Comments
T1 Z601 pin1 N601-Out -43 dBm/
836.52 MHz
-13.2 dBm/
836.52 MHz
Output of N601 Driver, Input to
Tx SAW Filter
T2 Z601 pin 3 PA-In -25 dBm/
836.52 MHz
-15.4 dBm/
836.52 MHz
Output of Tx SAW, Input to PA
T3 N803 pin 8 PA-Out 5.0 dBm/
836.52 MHz
18.3 dBm/
836.52 MHz
Output of PA, Input to Isolator
T4 Z803T Iso-Out 2.2 dBm/
836.52 MHz
10.3 dBm/
836.52 MHz
Output of Isolator, Input to
Duplexer
T5 C603L IF-Out -29 dBm/
228.6 MHz
-24 dBm/
228.6 MHz
Tx IF Probing Point at IF Filter
T6 C638T, C654T,
C633R,
C635R,
C603LR
VR5 2.7 V dc VHF VCO/PLL, IQ modulator
supply from UEM
T7 C655R VR7 2.7 V dc UHF PLL Supply from UEM