Colour Television Chassis: M123A
37
No
Yes
Is it mute at
Pin 1 of
IC601?
Yes
No sound
Is the speaker
Replace the speaker
Apply the pointer of multimeter at
RX1K
¡
connect one probe to
GND, use another to touch P3, P5 of
IC601, Is there interference noise
from the speaker.
No
Check power
supply of
IC601
Yes
Is the waveform
at P47 of IC1001
ok?
Yes
Check/Replace the power
supply of IC1001. Then
RESET
NG
Is the
BUS ok?
Check IC201 and
the relative circuit
No
No
Check/Replace
Q1001, X1002.
NG
Is the waveform at
P31 of IC201 ok?
Replace IC201
No
Yes
Replac
e IC601
Check/Replace
Q604,Q605.
No
Figure 6 No Sound
Is both +14V and -14V ok?
Yes
No
Is the signal at P1 of
IC301 ok?
Check/Replace IC301
Check signal at P16 of
IC201
No
Check/Replace
IC201,C234
Yes
Check/Replace R244,
R306
Yes
Check/Replace R405,
R409, D403, D402
No
Figure 7 No Vertical Scanning
5. Faultfinding and Test Point with Waveform Diagram
5.1 Faultfinding
Summary of Contents for CTR1042
Page 41: ...Colour Television Chassis M123A 41 6 Block Diagram and I2C 6 1 Block Diagram...
Page 49: ...Colour Television Chassis M123A 49 7 Electrical Diagrams 7 10 CRT Panel...
Page 52: ...Colour Television Chassis M123A 52 8 PCB 8 1 Main PCB...
Page 53: ...Colour Television Chassis M123A 53 8 PCB 8 2 CRT PCB...
Page 54: ...Colour Television Chassis M123A 54 8 PCB 8 3 MPX PCB...
Page 55: ...Colour Television Chassis M123A 55 8 PCB 8 4 SIDE AV PCB...
