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4 . TROUBLE SHOOTING
Graph 4-1(a)
Graph 4-1(b)
Check Pin 3.
Refer to Graph 4-1 (b)
Check Pin 4.
Refer to Graph 4-1 (a)
Yes
No
No
2.7V OK?
Yes
Changing X500
VCTCXO Circuit is OK
See next Page to check
ANT SW & Mobile SW
Check U101, PMIC
TEST POINT
CIRCUIT
13 MHz O.K?
Checking Flow
Waveform
AFC
X500
2V75_VVCXO
13MHz
C536
22u
VCC
GNO
OUT VCONT
100
R514
1
2
3
1
4
C538
1000p
15K
R516
(2) Checking VCTCXO Circuit
Summary of Contents for B2070
Page 68: ... 67 4 TROUBLE SHOOTING TEST POINT 4 6 LCD Trouble ...
Page 72: ... 71 4 TROUBLE SHOOTING TEST POINT 4 8 Speaker Trouble ...
Page 79: ... 78 4 TROUBLE SHOOTING 4 11 KEY backlight Trouble TEST POINT ...
Page 107: ... 106 8 PCB LAYOUT Figure 8 1 B2070 BOTTOM SIDE PCB LAYOUT ...
Page 108: ... 107 8 PCB LAYOUT Figure 8 1 B2070 TOP SIDE PCB LAYOUT ...
Page 109: ... 108 ...
Page 117: ...10 STAND ALONE TEST 116 Figure 10 2 HW test setting Figure 10 3 Ramping profile ...
Page 121: ... 120 ...
Page 123: ... 122 ...