Nokia 2255 Manual page 14

2255 (RM-97)
RF Description and Troubleshooting
Table 1 shows the Tx DC/RF test points to probe (see Figure 10 and Figure 11) when
troubleshooting the cell transmitter path. It is recommended that you follow the steps in
order.
Test Point FUnction
TP1 Z7000 N7000 - Out
pin 1
TP2 Z7000 PA - In
pin 3
TP3 Z7400 PA - Out
In
TP4 Z7400 Iso - Out
Out
TP5 C7002 IF - Out
TP6 VR5
TP7 VR7
TP8 VR2
TP9 R7002 VAGC-RF
TP91 R7001 VAGC-IF
TP10 VIO-Tx
TP11 VBAT
TP12 VCC
TP13 C7407 VG/Vref
Page 14
Table 1: Tx DC test points
Typical Value/
Frequency
HP85024A
-40 dBm/ 1MHz
836.52MHz
-26 dBm/ 1MHz
836.52MHz
5.0 dBm/ 1MHz
836.52MHz
2.5 dBm/ 1MHz
836.52MHz
-29 dBm/ 1MHz
228.6MHz
2.75V dc
2.75V dc
2.75V dc
0.2 to 1.8V dc
1.8V
3.2V dc
3.1V dc (High Gain)
4.6V dc (Enable)
©2005 Nokia Corporation
Nokia Customer Care
Typical Value/
Frequency Comments
Prod Probe
-13.2dBm/ Output of N7000 Driver,
836.52MHz Input to Tx SAW Filter
-15.4 dBm/ Output of Tx SAW,
836.52MHz Input to PA
18.3 dBm/ Input to Isolator
836.52MHz
10.3 dBm/ Output of Isolator,
836.52MHz Input to Duplexer
-24 dBm/ Tx IF probing point at IF
228.6MHz filter
VHF VCO/PLL, IQ modulator
supply from UEM
UHF PLL supply from UEM
Mixer, driver, and IF supply
from UEM
Tx AGC control voltage
from UPP.
0.2V = Max Gain
1.8V = Min Gain
Supply for digital circuits
from UEM
Battery voltage (nominal
voltage 3.7V dc)
Main PA supply voltage
from PMIC.
Lgain=0.8V, Mgain=1.25V,
Hgain=Vbat
PA gate voltage (Enable/
Disable). Disable=0V
Company Confidential ISSUE 1 10/2005