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Nokia Customer Care
Troubleshooting Instructions
Company confidential
NPL-4/5/
Issue 2 05/05
Copyright
© 2005
Nokia Corporation. All rights reserved.
Page 37
GMSK
Use Phoenix to select
TX_Data Type: "1" or "0"
TX Power Level: 10
Ch37
Ensure Vbatt=3.9 V
Yes
Oscilloscope
R702
Mode
Vdc = 0 Volt
R525
VREF01
Vdc = 1.35 Volt
Check
C520
VR2
Vdc = 2.78 Volt
No
Base Band
TXP testpoint
TXP
Vdc = 1.8 Volt
C552
VR5
Vdc = 2.78 Volt
C574
VR3
Vdc = 2.78 Volt
Yes
Oscilloscope
C535
TXIOUTP
67kHz
Vac = 0.4 Vpp, Vdc =
1.1 V
No Check
C535
TXIOUTN
67kHz
Vac = 0.4 Vpp, Vdc =
1.1 V
Base
Band
C536
TXQOUTP
67kHz
Vac = 0.4 Vpp, Vdc =
1.1 V
C536
TXQOUTN
67kHz
Vac = 0.4 Vpp, Vdc =
1.1 V
Yes
Oscilloscope
C713
VTXB_900
Vdc = 2.78 Volt
No
Check:
VC1
CONT1
Vdc = 0 Volt
Helgo Serial Interface
VC2
CONT2
Vdc = 0 Volt
Helgo
VC3
CONT3
Vdc = 2.7 Volt
R712
VPCTRL_90
0
Vdc > 1 Volt
Yes
Spectrum analyzer
No
Check
Z700 out, R706 in
RFin_850/
900
P>= -3 dBm, 897.4MHz
EGSM TX SAW Filter
Compare
with
good
sample
Helgo
Yes
Synthesizer
Use Phoenix to select
TX_Data Type: Random
TX Power Level: 10
Yes
Spectrum analyzer
Check PA N700
Z809TX1 (PA N700
No
Check Power Loop
Spectrum analyzer
Check PA N700
Z809TX1 (PA N700
RFOut_850/900)
No Check
Power
Loop
Power = +25 dBm, 897.4
MHz
Check
TXC
Yes
Spectrum analyzer
Check
RF-connector No
Pout
= +23 dBm, 897.4 MHz
Antenna Switch (Z809)
Yes
GSM900 TX
OK