Sony KD-34XBR2 Training Manual page 92

There is also a possibility that a simultaneous loss of communications from the B (IC001) to the A board (IC3006)
and loss of horizontal drive will result in shutdown without a blinking LED, possibly from a broken or contaminated
A board. See Standby light blinks 7X or the overall protection block diagram 33.
Standby light blinks two times – TV Shutdown
The +135V OCP monitoring circuits are located on the G board, but the indicating circuit is on the B board. This
circuit monitors current drawn by the horizontal regulator that provides power for the horizontal output stage. See
Figure 20-6 below:
AC
Pwr
On
Circuit - Refer to Figure 20-7 for the following circuit description of the 135V load and current sensing circuit.
135V Loads (D, C, A and V boards)
The 135V OCP circuit monitors the current on the +135V line from the Secondary Power Supply to the D, C, A and
V boards. Of all the +135 volt line loads listed, the D board is the most demanding:
•
Horiz Output (Q5030) and PWM (Q5003) stage (D board).
•
The HOT on the D board in turn supplies +200V to the RGB Video Output ICs (C board).
•
33V tuning voltage to analog tuners (A board).
•
Velocity modulation coils (V board).
CN6001
AC IN
RY6001
AC RELAY
Q6120
G BD.
4
AC
A BD. RELAY
A26
B BD.
69
44
IC001
MAIN
MICRO
45
50
STBY
LED
Q522
(H BD.)
AC
Relay
AC Relay
Main Micro IC001
SURGE
V SENSE (ENABLE 2)
RELAY
SW.
CIRCUIT
STANDBY
D6001
5V
Q6105
P
R6119
R6195
CN001/
CN3020
C6146
10
2X
D6124
OCP
C25
6
+
C6102
100
3X
STBY 5V
OVP
A25
7
CN3016/
CN6101
STANDBY
A BD.
5V
FIGURE 20-7 - PROTECTION - 2X, 3X INDICATION - RA-5 CHASSIS
Figure 20-6
Sec P.S.
Main Relay
IC6001,
T6001
SECOND. P.S
R6041
T6001
R6099
PRI
P.S
PROTECT
LATCH
Q6119
AC IN OVP
N
15VOVP
22VOCP
(NO
INDICATION)
D6123
OCP
+
1
-
R6142
OVP
-
7
+
IC6102
uPC393C
STBY 5V
89
20. RA-5A Chassis Protection Block
OCP
Stby LED Indicator
D6104
R6102
270k
R6101
4.7k
R6118
0.22
G BD.
0.27V
ZENER
3
R6104 REF.
560
2
2
IC6103
R6103
uPC
4.7k
1
1093J
6
3
2.5V
5
R6110
CN6106/
+135V
CN8013
9
D BD.
HV REG/
HV OUT,
H OUT REG/
H OUT,
VIDEO OUT
P.S
10
A BD.
TUNER 33V
V BD.
VEL MOD
COILS
28TVP12 1345 9/4/01