Sony KV-14FV1B, Service Manual

Page: 6 / 84

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6. SELF-DIAGNOSTIC CIRCUIT
[+B overcurrent]
Owing to current increase voltage of R679 decrease and that it make Q611 and Q612 to
become LOW and OFF RY601.
[+B over voltage]
When +B voltage become more than 142.5V, Q611 and Q612 pin become LOW and
RY601 OFF.
[Vertical deflection stopped]
Detect Vertical deflection Pulse lost by IC001
^º
pin of micro computer.
Mute the picture at
!∞
pin of IC301 that performed by Y/C/J.
[White balance]
Detect when R.G.B. output wrong level balance of automatic white balance detecting
standard pulse which detect cathode current, or which become low almost.
CRT
7
3
62
53
60
49
47
64
21
34
35
15
SCL1
SDA1
V PULSE
LED
OVP
RY603
RELAY
Q601
ITEM 2.
Over voltage
Detection(OCP)
BOOST
VCC
IC501
IC301
Y/C/J
SDA
SCL
IK IN
VM OUT
R,G,B STOP
To item 2 and 5 via bus line
MEMORY
V
•
STOP
IC002
ITEM 4.
Auto cut-off white balance detection(AKB)
D1304
FBT
(T801)
C504
✩
Diagnostic screen display
Q606
Q611
Q612
R679
D502
R656
+B LINE
Q502
Q501
C505
R510
IC001
µ
-COM
LED flash
STANDBY
lamp
3 4
2 1
ITEM 2
Over current
Detection(OVP)
ITEM 3.
Vertical Deflection
output Detection
(V
•
STOP)
R611
VCR PWR
62 62
–
IC901
TELE TEXT
R • G • B
D636