Nokia RM-94 Rf Troubleshooting Instructions page 25

RM-94
6(b) - RF Troubleshooting
GMSK
TX_Data Type: Random
TX Power Level: 5
Ch700
Ensure Vbatt=3.6 V
Yes
Oscilloscope
C7711
R7511
C7512
TXP testpoint
C7517
R7516
Yes
Oscilloscope
C7529
C7529
C7530
C7530
Yes
Oscilloscope
C7709
VC1
VC2
VC3
R7715
Yes
Spectrum analyzer
T7700 out, R7709 in
Yes
Spectrum analyzer
Z7800 TX2 (PA N7700
RFOut_1800/1900)
Power = +21.6 dBm,
1747.8 MHz
Yes
Spectrum analyzer
RF@Test-Jig
Pout
= +20 dBm, 1747.8 MHz
Yes
GSM 1800 TX
OK
Issue 1 04/2005
Mode
VREF01
Vdc =
VR2
Vdc =
TXP V =
VR5
Vdc =
VR3 Vdc =
TXIOUTP Vac = 0.4 Vpp, Vdc =
TXIOUTN
Vac = 0.4 Vpp, Vdc =
TXQOUTP
Vac = 0.4 Vpp, Vdc =
TXQOUTN Vac = 0.4 Vpp, Vdc =
VTXB_1800
V = 2.7 Volt
_1900
CONT1
V = 2.7 Volt
CONT2
V = 2.7 Volt
CONT3
VPCTRL_18
V > 1.14 Volt
00_1900
RFin_180 P> 2 dBm, 1747.8MHz
0/1900
Compare with good
Check PA N7700
No Check Power Loop
(TXC, Vpctrl 1800 1900,
No
Antenna Switch (Z7800)
COMPANY CONFIDENTIAL
Copyright © 2005 Nokia. All Rights Reserved.
V = 0 Volt
1.35 Volt
2.78 Volt No
1.8 Volt
2.78 Volt
2.78 Volt
No
1.2 V
1.2 V
1.2 V
1.2 V
No
V = 0 Volt
No
sample
DET)
Check
Nokia Customer Care
Check
Baseband
Check
Baseband
Check
Helgo Serial Interface
Helgo
Check
T7700 Balun
Helgo
Synthesizer
25