Sony 17VC Troubleshooting

REVISED

17VC

OPERATION MANUAL
TROUBLESHOOTING MANUAL

CHASSIS

TABLE OF CONTENTS

CIRCUIT DESCRIPTION

D Board (Power Supply Section) ............... 2

D Board (Deflection Section) .................... 11

A Board ................................................... 21

U Board ................................................... 24

GENERAL TROUBLESHOOTING ................ 26

PARTS LEVEL BOARD REPAIR ................. 37

TRINITRON® COLOR COMPUTER DISPLAY

9-978-878-02

- 1 -

CIRCUIT DESCRIPTION

f

f

A

D BOARD POWER SUPPLY SECTION

Power Supply Electrical Circuit

The power supply is located on the D Board. It has three modes of operation that are controlled by a microprocessor. The
topology is a discontinuous mode flyback converter with photocoupler feedback for regulating the secondary voltages.
Circuit operation and troubleshooting are explained in the following sections:

Operation Modes Secondary Circuitry
AC Input Protection Circuits
Degauss Circuit Troubleshooting
Primary Circuitry USB/Audio Power Circuit

Operation Modes

The power supply has four modes of operation, off , active off, suspend/standby and active on. These modes are
related to power savings and are indicated by the front panel LED. Additional indications are failure diagnostics and aging
mode. The table below lists operation mode, condition and LED status.

Mode Syncs Condition LED

Off N/A Power Switch Off Off

Active Off No H and/or V Low Power, Heater Off Amber

Active On H and V Present Phase Locked, Normal Operation Green

Failure 1 N/A HV Failure Amber 0.5s<-->Off 0.5s

Failure 2 N/A H Stop, V Stop, S Cap Failure Amber 1.5s<-->Off 0.5s

Failure 3 N/A ABL Failure Amber 0.5s<-->Off 1.5s

Aging/Self Test No H and V Aging Raster or Test Pattern Amber 0.5s<-->Off 0.5s

Green 0.5s<-->Off 0.5s

Amber 0.5s<-->Off 0.5s

Except for power switch off, all modes of operation are controlled by the microprocessor located on the D Board. The
failure modes are detected by the microprocessor and the power supply is forced into active off mode. These functions
are discussed later (Deflection).

With the AC cord attached to the monitor and connected to an AC source, the monitor will be off until the power switch is
turned on. When the power switch is turned on, the power supply starts and is in active off mode. The next step is active
on mode. The active off power saving mode is activated by the microprocessor based upon the absence of either H or V
sync. If H and/or V sync signals are not present, the power supply is set to active off mode.

Power supply operation control signals are "Remote Sw", "Power Sw" and "PFC Sw". During active off mode, Remote Sw
and Power Sw are digital low and PFC Sw is digital high. To enter active on mode, the microprocessor sets PFC Sw to
digital low, then 300mS later, Remote Sw and Power Sw are set to digital high.

Output Of

180V (B+) 0V +13V +179V

80V 0V +6V +79V

+15V 0V +1V +15V

-15V 0V -1V -15V

+12V 0V 0V +12V

5V 0V 0V +5V

Heater 0V 0V +6.3V

STBY 5V 0V +5V +5V

Active Of

ctive On

- 2 -

AC Input and Degauss

THP600A

THP600

2

0

6

N

C

P

2

DGC1

DGC2

1

0

6

N

C

NC

NC

P

4

1

2

1

0

6

H

T

5

.

4

S

M

R

V

0

2

2

S

O

P

:

2

0

6

F

N

C

0

0

6

P

3

N

1

V

C

N

2

L

3

C

A

6

0

6

1

.

0

2

5

6

F

0

1

5

A

2

5

V

0

L

L

:

T

F

1

2

4

0

7

4

0

V

3

4

6

C

4

3

7

4

0

p

0

2

5

V

0

0

6

6

C

p

0

4

0

7

2

5

0

V

6

R

0

6

C

0

0

2

.

7

2

5

4

5

6

0

k

8

2

/

1

2

W

V

R

:

C

6

0

0

R

T

H

1

3

1

0

W

3

.

4

R

6

Y

0

6

0

.

9

8

4

A

1

2

3

1

3

6

C

2

1

V

1

0

6

G

S

S

E

U

D

G

A

S

1

0

6

1

0

6

2

D

0

T

S

1

-

5

S

D

1

9

2

1

6

D

1

0

0

6

B

S

4

D

L

.

T

C

E

R

C

A

Q

S

E

P

3

4

T

1

-

C

A

T

D

R

D

Y

.

V

A

L

E

R

1. AC Input Section

The AC input section provides EMI filtering, input protection, surge limiting and CRT degauss operation.

EMI Filter

The EMI filter comprises CN600 (inlet with filter), X-capacitors C604 and C605, Y-capacitors C660 and C643 and the
line filter transformer, LF602. Input protection is provided by F601and VA601; surge current limiting by thermistor
TH600 and resistor R600. Degauss is explained in the next section.

Degauss Circuit

The degauss circuit is used to demagnetize the CRT. After power on, the microprocessor located on the D Board sets the
degauss signal to digital high and Q601 turns on relay RY601. This allows AC current into the degaussing coil through
posistor TH601. The current heats up the posistor and the resistance increases, this dampens the current in the degauss
coil to nearly zero. Duration time is approximately 5-6 seconds and the microprocessor then shuts off RY601, which
disconnects the degauss coil from the AC line. This operation should sufficiently demagnetize the CRT.

2. Primary Circuitry Section

IC601

The heart of the primary section is the TEA1504/N2 power supply controller, IC601. The following describes the functions
of each pin.

Pin 1  Vin: This is a MOSFET drain connection internal to IC601, which is connected directly to the DC mains voltage rail.
The startup current source derives power from the DC mains via the Vin pin. It supplies current to charge the Vaux (IC
supply) capacitors C616, C617 and C681 and also provides current to the IC601 control circuitry.

Pin 2  HVS: High voltage safety spacer pin is a no connection.

Pin 3  NC: Connected to primary side DC mains return.

Pin 4  Driver: Outputs the pulse width modulated gate drive for switching transistor Q602. Maximum duty cycle is set

internally at 80%.

- 3 -

Pin 5  Isense: Provides cycle by cycle over current protection by turning off pin 4 driver output when Q602 current
exceeds the current limit corresponding to 500mV at pin 5. This pin typically provides 425nS of leading edge blanking time.
The threshold voltage for switch over to low frequency (low power) operation is sensed by pin 5. When the voltage sensed
at pin 5 is below 165mV, IC601 transitions from operating at high frequency (56.5KHz) to low frequency (23.5KHz).

Pin 6  Vaux: IC601 supply pin. An internal current source from IC601 charges the Vaux capacitors C616, C617 and C681
for startup. Once the Vaux capacitors are charged to the startup voltage level (11V), then IC601 starts switching pin 4 driver
output. The Vaux is also supplied by an auxiliary winding from T601 on the primary side once the secondary output voltages
attain their nominal operating voltage values. Pin 6 also provides under voltage lockout detection (8V) and over voltage
protection (14.7V).

Pin 7  DS: Provides the power supply for the driver output (pin 4).

Pin 8  Iref: Controls IC601 internal bias currents, which determines the pulse width modulated switching frequencies.

High frequency is 56.5KHz during active on mode. Low frequency is 23.5KHz during suspend/standby mode.

Pin 9  Vctrl: Feedback voltage for duty cycle control.

Pin 10  NC: No connection.

Pin 11  Gnd: Connected to primary side DC mains return.

Pin 12  NC: No connection.

Pin 13  Dem: Guarantees discontinuous conduction mode operation for the power supply. Verifies that T601 is demagne-

tized by not activating the next gate drive pulse until the primary side auxiliary winding of T601 is lower than the threshold
level of 65mV as detected at pin 13.

Pin 14  OOB: On/Off/Burst mode input signal. A voltage greater than 2.5V enables IC601.

Operation

The power supply is a discontinuous-mode flyback converter with photocoupler feedback for regulating the secondary
voltages. The PWM controls the pulse width of the gate drive.

When AC is applied to the power supply and IC601 pin 14 is greater than 2.5V, start up current is supplied though IC601 pin
1 to IC601 pin 6. Startup voltage is approximately 11V. After start up, the voltage to pin 6 and pin 7 of IC601 is supplied
through D620 connected to T601 pin 1. The first mode of operation is active off mode. The output drive pulse frequency
will be in burst mode operation.

When the power supply enters active on mode, the switching frequency will be 56.5KHz. The Vaux level will be approxi­mately 12.3 volts. OVP threshold is 14.7 volts and UVLO is 8.0 volts. Therefore, if the Vaux voltage is not correct, the
power supply will not operate properly.

Feedback from the secondary side comes through IC603 and IC604, which is connected to IC601 pin 9. (See diagram on
page 5.)

3. Secondary Circuitry Section

The secondary section consists of the following circuits: Rectifier diodes and filters for all output voltages, +5/12 volt
regulators, +5 standby regulator, heater voltage regulator, voltage feedback circuit, active off mode feedback, and protec­tion circuits. This section will describe each circuit and its function.

Secondary Rectifiers

The secondary rectifiers supply the following voltages: 180V (B+) for deflection and video, 80V for video, ±15V for
deflection and regulators, 6.3V for heater regulator, and +5V standby regulator.

- 4 -

2

0

C

6

0

p

1

0

0

V

5

0

6

7

p

4

k

V

2

7

6

6

R

0

1

3

5

-

1

V

5

5

6

0

R

)

.

5

7

W

(

J

1

C

6

0

3

3

1

3

6

J

W

0

4

0

)

5

7

.

W

(

J

3

6

1

R

M

.

7

4

W

/

2

1

2

0

R

6

S

M

7

4

.

W

2

1

/

2

1

5

6

R

0

k

8

6

I

P

H

:

C

5

-

D

Z

U

2

3

6

D

B

2

1

7

-

7

T

-

-

Z

J

T

M

1

1

S

S

1

6

5

C

6

0

P

I

C

H

:

8

6

1

R

6

1

R

0

2

2

k

1

P

-

C

R

N

:

C

-

N

R

:

1

D

6

7

-

7

-

-

T

J

T

Z

M

1

9

R

0

J

0

2

6

D

E

-

T

D

6

-

9

0

P

0

.

4

P

I

0

C

H

:

1

4

6

1

C

1

.

0

0

9

3

6

R

I

P

H

C

4

:

B

7

0

4

5

2

6

B

3

1

7

-

1

6

6

1

R

M

.

0

1

9

0

P

H

I

C

:

D

5

T

2

8

6

9

R

k

5

6

P

H

I

C

:

5

6

1

C

2

0

2

.

0

P

H

I

C

:

6

6

0

R

k

7

0

4

B

7

P

-

C

R

N

:

1

0

6

I

C

2

N

4

-

0

1

5

A

E

T

.

G

E

R

W

S

L

O

R

N

T

O

C

4

O

B

O

1

3

M

E

D

1

2

N

C

1

1

R

D

D

N

G

1

0

I

S

N

C

1

V

T

C

R

L

9

E

R

F

I

8

0

6

2

R

k

3

3

P

-

C

N

R

:

J

-

Z

M

T

I

6

L

P

T

O

C

T

O

P

H

C

C

C

R

4

3

E

4

7

6

C

0

p

7

4

0

V

0

5

B

N

I

V

H

E

V

I

N

E

S

A

V

3

6

D

7

-

T

0

6

C

1

D

2

U

P

O

T

N

O

I

4

A

S

O

R

R

O

T

1

H

E

S

V

2

C

N

3

R

4

3

6

0

R

k

.

8

1

C

R

:

E

5

5

0

6

C

0

0

6

8

I

H

:

C

X

U

6

5

6

5

R

0

1

0

D

S

7

8

1

8

-

7

1

6

8

C

7

4

.

V

5

0

3

-

Y

4

E

R

L

L

R

O

1

2

2

6

4

R

0

3

9

P

-

C

R

N

:

3

4

6

0

C

N

A

L

3

1

P

A

M

R

2

1

2

6

C

6

8

0

0

.

0

V

5

2

1

2

R

6

5

k

7

P

I

C

H

:

2

0

Q

6

4

3

8

K

2

S

2

2

6

0

Q

K

I

T

N

A

S

G

.

E

R

W

S

T

U

O

2

1

R

6

2

2

W

4

1

/

4

U

F

D

Z

M

T

p

P

R

6

N

:

R

1

6

6

C

2

2

V

5

2

C

S

2

1

1

6

C

0

p

8

6

I

C

H

:

1

1

C

6

0

2

7

k

2

S

7

6

0

D

2

3

G

0

7

0

7

6

5

R

8

0

6

8

-

1

J

2

3

6

R

3

3

J

Z

T

M

4

6

5

R

4

4

2

1

R

6

9

.

3

0

7

4

0

.

2

2

1

W

1

W

P

-

C

S

R

:

S

R

:

2

6

2

R

2

2

I

P

H

:

C

7

6

1

C

C

2

2

V

2

5

1

7

R

6

0

0

1

P

I

C

H

:

:

3

3

6

C

.

1

0

I

P

H

:

C

4

0

6

Q

1

A

1

3

3

T

R

O

P

3

4

C

6

p

0

7

0

4

P

I

C

H

:

4

3

R

6

P

k

2

8

P

C

N

-

R

:

A

A

0

V

B

B

3

0

A

6

V

0

1

T

6

R

T

S

E

W

5

6

3

R

k

2

2

W

3

S

:

R

6

6

0

D

2

3

G

7

0

0

4

U

F

3

p

1

9

6

R

5

6

6

R

V

5

k

.

1

5

k

.

1

W

2

2

W

S

:

R

R

S

:

6

6

1

D

B

7

.

-

4

7

-

7

T

-

2

D

6

D

1

0

P

G

R

0

4

R

6

1

D

P

R

:

F

8

6

1

1

0

.

T

:

P

5

6

C

6

.

1

0

5

V

2

P

I

C

H

1

1

R

6

2

2

I

P

C

H

:

D

6

-

7

T

J

-

Z

T

M

7

4

R

6

0

k

1

8

0

6

R

k

5

0

1

N

:

R

5

0

R

6

0

k

1

2

N

:

R

4

8

6

R

6

k

.

5

C

P

N

-

R

:

0

9

6

R

9

k

.

3

P

-

C

N

:

R

N

0

9

1

1

1

7

1

2

3

6

1

5

1

5

6

4

1

7

1

8

1

1

0

3

G

2

Y

B

T

S

0

8

C

6

2

0

2

5

0

B

2

-

1

7

4

1

2

V

5

1

4

C

6

0

0

1

V

6

1

8

6

2

R

k

.

1

9

P

-

C

N

:

R

9

6

4

R

k

.

2

2

P

-

C

R

N

:

V

3

.

6

R

T

E

A

T

H

O

E

0

W

3

1

6

1

D

A

6

U

2

-

M

C

F

0

1

6

F

B

2

1

C

6

4

7

0

V

2

5

C

7

6

1

D

R

6

1

0

G

P

1

1

8

6

D

2

S

1

-

G

N

F

M

2

3

C

6

0

0

1

0

V

5

2

2

2

D

6

S

2

G

1

-

M

N

F

6

0

C

0

0

1

2

5

D

1

0

7

6

I

C

5

T

0

B

A

G

E

R

V

5

O

G

1

J
D

D

T

A

N

U

V

G

O

0

3

C

6

0

.

1

V

0

1

7

3

C

6

6

0

C

0

2

2

7

4

V

6

1

V

1

0

G

0

7

0

4

U

F

D

T

B

5

6

2

R

8

1

0

k

.

2

2

W

/

2

1

7

6

2

R

7

.

4

0

W

/

2

1

2

6

0

L

S

S

1

2

6

2

0

0

1

V

0

0

6

0

L

V

5

1

-

0

6

L

6

0

0

1

3

0

V

1

9

6

D

2

S

1

-

G

N

M

F

4

6

1

D

A

2

T

-

S

6

N

.

3

I

2

0

6

I

C

V

T

-

S

0

A

0

A

B

G

E

R

R

E

A

T

E

H

C

L

C

T

V

C

3

6

0

D

12345

-

2

9

1

S

1

S

1

0

7

R

6

1

2

k

2

I

P

C

H

:

2

6

1

D

6

3

C

B

2

3

1

3

6

9

G

4

1

V

9

6

1

C

2

0

2

.

0

0

P

H

I

:

C

B

1

6

2

D

D

5

T

2

9

-

1

1

V

0

8

V

5

1

4

2

5

C

6

0

0

2

2

5

V

2

2

C

6

0

3

3

6

1

5

.

R

1

T

D

5

:

8

2

6

C

4

7

.

0

5

V

2

I

P

H

:

C

F

W
S

6

6

3

R

R
W

k

7

4

P

W

1

0

6

R

6

k

7

4

W

1

6

6

2

R

k

.

2

2

I

P

H

:

C

3

6

0

Q

K

A

E

1

4

1

C

D

T

R

T

E

A

H

E

W

S

4

0

V

7

9

6

2

.

W

1

S

R

W
S

R
W
P

+5/12 Volt Regulator

IC605 is the +12V regulator and IC608 is the +5V regulator. The output voltages are supplied to the microprocessor,
deflection and video circuits. The +15V line provides the input voltage for +12V regulator; the +12V line provides the input
voltage for +5V regulator. During active off mode, the +12V regulator is disabled via Remote Sw and subsequently the 5V
regulator is disabled.

+5V Standby Circuit

IC607 is the standby 5V regulator. In the active on mode the input to the regulator is supplied from T601 winding 14-13.
During the active off mode, the regulator input is supplied from T601 winding 10-13 via D612 and D613. Typical input
voltages to the regulator are active on mode: 9.5V; active off mode: 11.5V.

Heater Voltage Regulator

Heater filament voltage is supplied by T601 winding 14-13 and is regulated by IC602 to 6.3V during active on mode. IC602
output is turned on and off by the Power Sw control line at pin 1, CTL. The output is off during active off mode.

Feedback Circuit

The feedback circuit is divided into two sections. One is for active on mode; the other for active off mode. The follow­ing two sections explains the theory and operation.

Active On Mode Feedback

Shunt regulator IC604 regulates the B+ line to 179.2V by sinking current through the opto coupler 1C603 to ground. The

- 5 -

Feedback Circuits

2

0

C

6

0

p

1

0

0

V

5

0

6

7

p

4

k

V

2

7

6

6

R

0

1

3

5

-

1

V

5

5

6

0

R

)

.

5

7

W

(

J

1

0

C

6

0

3

3

1

3

6

J

W

W

(

J

3

6

1

R

M

.

7

4

W

/

2

1

2

0

R

6

6

S

M

7

4

.

W

2

1

/

2

1

5

6

R

0

k

8

6

I

P

H

:

C

5

T

-

D

Z

2

6

D

7

7

T

-

-

Z

J

T

M

U

3

B

2

1

-

D

1

1

S

S

1

6

5

C

6

0

P

I

C

H

:

8

6

1

R

0

6

1

R

0

2

2

k

1

P

-

C

R

N

:

C

-

N

R

:

0

1

D

6

7

-

7

-

-

T

J

T

Z

M

1

9

R

0

J

0

2

D

E

-

0

6

-

9

P

.

4

P

I

0

C

H

:

1

4

6

1

C

1

.

0

0

9

3

6

R

I

P

H

C

4

:

B

7

0

4

5

2

6

B

3

1

7

-

1

6

6

1

R

M

.

0

1

9

P

H

I

C

:

D

5

T

2

8

6

9

R

k

5

6

P

H

I

C

:

5

6

1

C

2

0

2

.

0

P

H

I

C

:

6

6

0

R

k

7

0

4

B

7

P

-

C

R

N

:

1

0

6

I

C

2

N

4

-

0

1

5

A

E

T

.

G

E

R

W

S

L

O

R

N

T

O

C

4

N

I

V

OOB

1

3

HVS

M

E

D

1

2

C

N

N

C

1

1

E

R

RIV

D

D

N

G

1

0

E

ENS

I

S

N

C

1

X

A

U

V

VCT

R

L

9

D

S

REF

I

8

0

6

2

R

k

3

3

8

3

6

D

P

-

C

N

R

:

1

8

-

7

7

-

T

J

-

Z

M

T

0

3

6

C

I

-

Y

4

1

D

2

6

L

P

T

E

R

L

U

P

O

O

C

T

O

P

H

L

R

O

T

N

C

O

C

C

R

4

3

4

6

0

C

I

A

L

3

1

4

A

S

A

M

O

R

R

R

E

R

7

C

:

4

7

6

C

0

p

7

4

0

V

0

5

B

6

O Q

T

1

I

ATS

H

E

2

1

R

6

2

2

2

W

4

1

/

3

4

U

F

D

Z

M

T

4

3

6

0

R

k

.

8

1

C

R

:

5

5

0

6

C

0

p

0

6

8

I

P

H

:

C

6

R

6

5

6

5

R

N

:

R

0

1

0

7

1

6

6

C

2

2

V

5

2

1

6

8

C

7

4

.

V

5

0

1

2

C

S

2

2

6

4

R

0

3

9

P

-

C

R

N

:

1

1

6

C

0

p

8

6

I

C

H

:

3

N

1

P

2

0

V

4

0

)

5

7

.

1

2

6

C

6

8

0

0

.

0

V

5

2

1

2

6

5

k

P

I

H

2

0

Q

6

4

3

8

K

2

S

2

2

0

K

N

G

.

E

R

W

S

T

U

O

1

C

6

0

2

7

V

k

2

S

7

6

0

D

2

3

G

0

7

0

7

6

5

R

8

0

6

8

-

1

J

2

3

6

R

3

3

J

-

Z

T

M

4

6

5

R

4

4

2

1

R

6

9

.

3

0

2

2

7

4

0

.

1

W

P

-

C

1

W

S

R

:

S

R

:

2

6

2

R

2

2

I

P

H

:

C

7

6

1

C

2

6

2

C

0

V

2

5

:

C

1

7

R

6

0

0

1

P

I

C

H

:

:

3

3

6

C

.

1

0

I

P

H

:

C

4

0

6

Q

1

A

1

3

3

T

R

O

P

3

4

C

6

p

0

7

0

4

P

I

C

H

:

4

3

R

6

P

k

2

8

P

C

N

-

R

:

A

A

B

B

3

0

A

6

V

0

1

T

6

R

T

S

E

W

5

6

3

R

k

2

2

W

3

S

:

R

6

6

0

D

2

3

G

7

0

0

4

U

F

3

p

1

9

6

R

5

6

6

R

5

k

.

1

5

k

.

1

W

2

2

W

S

:

R

R

S

:

6

6

1

D

B

7

.

-

4

7

-

7

T

0

2

D

6

G

D

1

0

P

G

R

0

4

R

6

1

D

P

R

:

F

8

1

1

.

T

P

C

5

6

6

.

1

0

5

V

2

P

I

C

H

1

1

R

6

2

2

I

P

C

H

:

D

6

-

7

T

J

-

Z

T

M

7

4

R

6

0

k

1

8

0

6

R

k

5

0

1

N

:

R

5

0

R

6

0

k

1

2

N

:

R

4

8

6

R

6

k

.

5

C

P

N

-

R

:

0

9

6

R

9

k

.

3

P

-

C

N

:

R

N

0

9

1

1

1

7

1

2

3

6

1

5

1

5

6

4

1

7

1

8

1

1

3

2

Y

B

T

S

0

8

6

2

0

2

5

0

B

2

-

1

7

4

1

2

V

5

1

4

C

6

0

0

1

V

6

1

8

6

2

R

k

.

1

9

P

-

C

N

:

R

9

6

4

R

k

.

2

2

P

-

C

R

N

:

V

3

.

6

R

T

E

A

T

H

O

E

0

W

3

1

6

1

D

A

6

U

2

-

M

C

F

0

1

6

F

B

2

1

C

6

4

7

0

V

2

5

C

7

6

1

D

R

6

1

0

G

P

1

1

8

6

D

2

S

1

-

G

N

F

M

2

3

C

6

0

0

1

0

V

5

2

L

2

2

D

6

S

2

G

1

-

M

N

F

6

0

C

0

0

1

2

5

D

1

0

7

6

I

C

5

T

0

B

A

G

E

R

V

5

O

G

1

J
D

D

T

A

N

U

V

G

O

0

3

C

6

0

.

1

V

0

1

7

3

C

6

6

0

C

0

2

2

7

4

V

6

1

V

1

0

G

0

7

0

4

U

F

D

T

B

5

6

2

R

8

1

0

k

.

2

2

W

/

2

1

7

6

2

R

7

.

4

0

W

/

2

1

2

6

0

L

S

S

1

2

6

2

0

0

1

V

0

0

6

0

L

V

5

1

-

0

6

6

0

0

1

3

0

V

1

9

6

D

2

S

1

-

G

N

M

F

4

6

1

D

A

2

T

-

S

6

N

.

3

I

2

0

6

I

C

V

T

-

S

0

A

0

A

B

G

E

R

R

E

A

T

E

H

C

L

C

T

V

C

3

6

0

D

12345

-

2

9

1

S

1

S

1

0

7

R

6

1

2

k

2

I

P

C

H

:

2

6

1

D

6

3

C

B

2

3

1

3

6

9

G

4

1

V

9

6

1

C

2

0

2

.

0

0

P

H

I

:

C

B

1

6

2

D

D

5

T

2

9

-

1

1

V

0

8

V

5

1

4

2

5

C

6

0

0

2

2

5

V

2

4

2

C

6

0

0

3

3

V

6

1

5

.

R

6

1

1

T

D

5

:

8

2

6

C

4

7

.

0

5

V

2

I

P

H

:

C

F

W
S

6

6

3

R

R
W

k

7

4

P

W

1

0

6

R

6

k

7

4

W

1

6

6

2

R

k

.

2

2

I

P

H

:

C

3

6

0

Q

K

A

E

1

4

1

C

D

T

R

T

E

A

H

E

W

S

7

9

2

.

W

S

R

W
S

R
W
P

reference voltage at IC604 pin 1 determines the sink current into pin 3. The reference voltage is set to 2.5 volts by
resistor divider R608, R650, R648, and R609. Since the B+ is connected to the resistor divider, any change in B+ voltage
is detected at the reference terminal. The shunt regulator will either increase or decrease the current into pin 3 in order
to decrease or increase the B+ voltage respectively and try to maintain the reference voltage to 2.50 volts. IC603 biases
it's phototransistor accordingly and drives IC601 pin 9 (Vctrl) which changes the duty cycle at IC601 pin 4 (driver) to
regulate the B+ voltage at 179.2V.

Active Off Mode Feedback

Power Sw control line is low (heater off) during active off mode and respectively Q603 is off. Voltage pulses from T601 pin
10 flow through C620, R636, and R660 triggering the gate of thyristor D613. D613 turns on effectively shorting the B+ rail
to the standby 5V regulator input; current flows from T601 pin 10 through D612 and D613 to the standby 5V regulator input.
When the standby 5V regulator input is increased to approximately 12.7V it forward biases zener diode D605 turning on
Q604 and sinks current through IC603 to ground. The standby 5V input supplies this current to IC603 pin 1. IC603 biases it's
phototransistor and drives current through D609 into IC601 pin 14 (OOB) triggering burst mode operation. IC601 pin 4
(driver) is pulled low turning off switching transistor Q602. T601 pin 1 (auxiliary winding) feedback pulses are discontin­ued and IC601 pin 6 (Vaux) decreases to 8V. IC601 internal current source then charges pin 6 (Vaux) to the startup voltage
level (11V) which starts switching pin 4 driver output. The feedback cycle is then repeated. The burst repetition rate is
approximately every 110mS and when IC601 pin 4 is switching its frequency is 23.5KHz.

- 6 -

J

Z

M

T

4. Protection Circuits

Protection Circuits

-

V

5

5

3

1

5

0

6

R

)

5

.

7

(

W

J

0

1

6

C

0

3

3

3

1

6

W

J

7

(

W

J

3

1

6

R

M

7

.

4

W

2

/

1

2

0

6

R

4

1

6

R

8

6

C

:

3

6

2

D

B

1

2

-

7

7

-

T

-

0

6

S

M

7

.

W

2

/

2

5

1

k

0

P

I

H

5

T

E

-

D

Z

U

6

D

9

1

S

1

S

1

5

6

6

C

0

P

I

H

C

:

8

1

6

R

0

1

6

R

0

2

2

k

1

P

C

-

N

R

:

P

C

-

N

R

:

0

6

1

D

4

-

7

-

7

T

-

Z

J

T

M

9

1

0

R

J

2

D

-

0

-

.

P

I

H

C

:

0

1

4

1

6

C

1

0

.

0

3

9

6

R

4

6

1

9

2

7

P

I

H

C

:

B

0

7

4

5

2

3

B

1

-

7

6

1

6

R

M

0

.

1

P

I

H

C

:

8

9

6

R

D

T

5

k

6

5

P

I

H

C

:

5

1

6

C

2

2

0

.

0

P

I

H

C

:

6

0

6

R

k

0

7

4

P

C

-

N

R

:

B

1

6

0

C

I

2

-

N

4

5

0

1

E

A

T

.

E

G

R

S

W

L

R

O

T

N

C

O

4

N

I

V

B

O

O

1

3

E

D

1

2

C

N

1

1

N

G

1

0

C

N

1

C

V

9

R

I

8

0

2

6

R

k

3

3

P

C

-

N

R

:

1

S

V

H

M

2

C

N

3

R

E

V

I

R

D

D

4

E

S

N

E

S

I

5

X

U

A

V

L

R

T

6

S

D

F

E

7

8

6

3

D

8

1

7

-

7

T

-

-

J

T

Z

M

6

R

7

H

C

:

7

4

6

C

p

0

7

4

V

0

0

5

B

0

6

Q

O

T

N

I

S

T

A

E

H

2

1

6

R

2

2

W

4

/

1

0

4

F

U

D

6

Z

J

T

M

3

0

6

R

k

8

.

1

C

R

:

0

5

6

C

p

0

0

8

6

P

I

H

C

:

2

6

R

5

5

6

R

2

-

N

R

:

0

0

1

6

R

2

H

C

:

6

1

6

C

2

2

V

5

2

1

8

6

C

7

.

4

V

0

5

V

0

0

4

)

5

.

2

1

6

C

8

6

0

.

0

V

0

5

2

1

2

k

5

P

I

2

0

Q

6

3

4

2

8

K

2

S

2

K

.

G

R

E

S

W

T

O

U

1

6

C

0

7

2

k

2

S

7

0

D

6

3

G

2

7

0

7

5

6

R

8

0

1

8

-

3

2

6

R

3

3

-

J

T

Z

M

4

5

6

R

4

4

1

6

R

9

3

.

0

7

4

.

0

2

W

1

W

1

P

C

S

R

:

S

R

:

2

2

2

P

I

7

1

6

C

2

2

6

C

V

5

2

0

:

ABA

B

3

0

6

A

V

5

3

6

R

k

2

2

W

3

S

R

:

0

6

6

D

3

G

2

7

0

0

4

F

U

3

p

9

1

6

R

6

5

6

R

V

k

5

.

1

k

5

.

1

W

2

W

2

S

R

:

S

R

:

1

6

6

D

B

.

7

4

7

-

7

-

T

2

0

6

D

3

2

D

G

0

P

1

G

R

0

4

6

R

1

D

R

P

F

:

8

1

1

.

T

P

1

0

6

T

T

R

S

W

E

N

9

7

6

5

4

1

2

0

1

1

1

2

1

3

1

5

1

6

1

7

1

8

1

4

1

The following are protection circuits: OCP, OVP, UVLO and secondary short circuits. OCP is pulse by pulse and is performed
on the primary side. OVP detects excessive output voltages. UVLO detects output under voltages. The following will explain
the operation of these functions.

OCP

OCP is activated if there is too much current passing through the switching power MOSFET, Q602. This condition will
occur if either the B+ line or 80 volt line is shorted.

R614 and R654 are the current sense resistors. Current through these resistors will produce a positive voltage. R623,
R624, R657 and C650 provide a voltage divider and filter to IC601 pin 5 (Isense). If the voltage level exceeds 0.5 volts, the
IC does pulse by pulse current limit and the output voltages are reduced. This condition can be audible and characterized by
a chirping sound.

OVP and UVLO

The OVP and UVLO functions are detected by IC601 pin 6 (Vaux). Vaux is typically 12.3V. In the event the regulation control
loop were to fail, the output voltages would either increase or decrease; then Vaux would increase or decrease respectively
via T601 transformer coupling. IC601 pin 6 will detect an OVP at 14.7V and UVLO at 8V turning off the driver output and
initiating a low dissipation safe-restart mode.

Secondary Short Circuits

Safe operation during secondary short circuits is provided by the demag function of IC601 pin 13. Demag protection
reduces the switching frequency, thereby reducing the input power level and providing safe operation. Demag also
provides a soft start function during startup gradually increasing the switching frequency until fixed frequency operation
is attained.

5. Troubleshooting

Warning

Before attempting to fix the power supply, safety should be considered first. Never connect test probes to the primary side
circuits, unless proper isolation has been installed. If isolation for the AC mains is not present, serious harm can occur.
Never assume you are safe.

- 7 -

Caution: C610 has a Slow Voltage Discharge

If the front panel power on/off button is switched to the off position prior to the AC mains input power being removed from
the monitor, then electrolytic capacitor C610 discharges with a long time constant. When the monitor cabinet cover and/or
EMI shield are removed, making the D board circuitry accessible during servicing or repair by qualified personnel, the
following procedure is recommended: Always remove the AC mains input power from the monitor prior to switching the
front panel on/off button to the off position. The AC mains input power should be removed from the monitor for a mini­mum of 30 seconds before the front panel on/off button is switched to the off position.

Caution: Do NOT Touch IC610 Component Tab or Heat Sink

IC610 component tab has an electrical voltage potential equivalent to the primary side return (approximately AC mains
input voltage potential). If IC610 heat sink insulator pad and/or shoulder washer busing are damaged or not assembled
correctly, then the IC610 heat sink will have an electrical voltage potential equivalent to primary side return (approximately
AC mains input voltage potential).

No Power

In the event that the monitor does not turn on, first verify input power is applied to CN600 and the front panel power button
is turned on; then check F601. If F601 is blown, the primary side circuitry should be checked. If the fuse is not blown, then
check the secondary side circuitry, especially the protection circuits. If these circuits are causing a no power symptom, the
problem can be more readily found.

AC Input and Degauss Circuit Trouble Shooting

For no power or nonoperating power supply, the AC input circuitry should be checked. Open or short circuit elements will
cause non-operation. Check F601, CN600, D601, R600, TH600 and R605 on the D Board. Check the front panel power
button for continuity.

If all elements are correct, check whether F601 breaks when power is applied and the power button is closed. If the fuse
does blow, there probably is a component shorted in the prmary circuitry.

The degauss will malfunction if CN601 is not connected. One problem could be loss of degauss signal from the micropro­cessor. This can be verified by using the manual degauss command found in the OSD menu. If the signal does not appear at
Q601 base, then it is possible that the microprocessor does not function correctly or standby 5V is not functioning.

The second step is to place a short across the AC terminals of RY601 for less than two seconds. If degauss operates then
check Q601 and RY601. If degauss does not work, check TH601 for an open condition and C631 for a short condition.

Primary Section

Three main areas can diagnose primary circuit failures. These are IC601, Q602 and Feedback system.
Visible checks of these areas will aid in finding problems. The following will discuss each section.

IC601

First apply AC to the monitor and check IC601 pin 4 output. If the output on pin 4 is not present, there could be problems
with Q602 and related parts or pin 14 could be less than 2.5 volts. Further, check Vaux level at pin 6. If it less than 11V,
the IC could be in safe-restart mode. If the voltage is very low, there could be a short on any of the IC pins. In reference
to ground, check the impedance of pin 1, 8 and 14. If any of these pins are shorted, replace the IC and check components
connected to the related pins. Take care that C616, C617 and C681 are fully discharged before replacing the IC.

Q602

The switching transistor can be damaged in various ways. These are related to voltage, current and temperature.

Check whether the transistor is shorted across drain and source terminals. If there is a short, F601, R605, R614, R654,
R623, R624, R657 and C650 should be checked. Additional components to check are D608, R603, R612 and IC601. If
Q602 is shorted, all these parts should be replaced.

Failure of a secondary rectifier diode can also cause Q602 to fail. Check 180V and 80V diodes for open or short
conditions. There is also a clamp circuit, which is used to clip the turn off spike found on Q602 drain. If the clamp
circuit is broken, it can cause Q602 failures. Check D606, C612 and R635. Also check the snubber circuit components
C613, D607, R619 and R656.

Secondary Circuit

Failure in the secondary circuits can be categorized by rectifier diodes, regulators, feedback loops and protection circuits.

- 8 -

These sections are interrelated and failure in one can affect another. Consequently, some failures will also affect the
primary circuitry.

Rectifier Section

Rectifier diode failures are not common, but do occur. Deflection, video and high voltage circuitry failures contribute to
diode damage. In the event a voltage is not present, check for shorts to ground, open or short diodes.

+5/12 Volt Regulator

If +12V or +5V output line is not available or the wrong voltage, IC605 or IC608 may be damaged. Before replacing
either IC, check for shorts or damaged parts along the output lines. If +12 volt does not appear, check the Remote Sw
signal from IC901 pin 6.

Standby 5V Circuit

Failure of this circuit can be affected by IC607. In case the circuit does not work properly, check D605, D614, R611 and
Q604. If these components are good, check the remaining circuit parts. Another possible influence can be the heater
circuit. Since both the standby 5V and heater voltages are produced by T6-1 winding 13-14.

Heater Voltage Regulator

This circuit may be affected by R697 or D619. If these parts are good, check the regulator output for a short to ground.
Shorts can occur on the video board. In the case of Power Sw signal.

Feedback Circuit

Problems with feed back can cause power supply shut down and low or high output voltages. First determine whether the
power supply is operating in active off, active on modes or not at all.

The power supply can be stuck in active off mode. The Remote Sw signal, Q603, Q604, D605 and IC603 can affect this
condition. Likewise, if the power supply is always in active on mode, the same items should be checked, along with
D612, D613, D621, C619, C620, R626, R636 and R660.

Checking for voltages at IC603 pins 1 and 2, IC604 pins 1 and 3 can solve more difficult problems. Additionally, IC603
pins 3 and 4, and IC601 pin 9 should be checked. If there are problems with these devices, 180V or standby 5V line, the
feedback systems will not work correctly. Also check the protection circuits.

Protection Circuits

OCP occurs when there is excessive current through Q602. Failures with Q510, Q507 or the video section could cause
this condition. These areas should be checked. OCP condition can also occur if R614 or R654 are open; if R623 or
R657 are shorted; or if R624 is open.

OVP usually occurs when the feedback loop is open, or loss of standby 5V. Isolate the OVP trigger condition, by first
checking the operation of the feedback loop.

6. USB/Audio Power Circuit

CAUTION: Do not touch IC610 component tab or heat sink. The IC610 component tab has an electrical voltage
potential equivalent to the primary side return (approximately AC mains voltage potential). If the IC610 heat sink insulator
pad and/or shoulder washer bushing are damaged or not assembled correctly, then the IC610 heat sink will have an electrical
voltage potential equivalent to the primary side return (approximately AC mains voltage potential).

The USB/Audio power supply circuit is a flyback converter that uses an integrated power mosfet and switch mode pwm
control IC (IC610). The circuit consists of IC610, T602, D633, PH601, IC611 and associated circuitry. Start up is
initiated when C675, connected to the CONTROL pin 1 is charged via a high voltage current source internal to IC610.
When CONTROL pin 1 reaches 5.8V, the control circuitry and mosfet are activated and a 10mS soft-start begins. The
typical mosfet DRAIN pin 7 switching frequency is 130 KHz with a ±4KHz jitter. The feedback loop consists of shunt
regulator IC611 and optocoupler PH601 that will regulate the secondary side output voltage at 6.5V and provide feedback
current to CONTROL pin 1. During normal operation, T602 bias winding pins 3-4 provide the charging current to maintain
CONTROL pin 1 at 5.8V; additionally the CONTROL pin 1 charging current that is regulated by IC611 and PH601 controls
the mosfet duty cycle to provide closed loop regulation.

The front panel power button controls the on/off function for the USB/Audio power circuit. When the power button is in
the OFF position, the MULTIFUNCTION pin 3 is shorted to CONTROL pin 1, turning off the power circuit. When the
power button is in the ON position, the MULTIFUNCTION pin 3 is shorted to primary side DC mains return, which enables
the power circuit.

- 9 -

2

1

S Cap Sws

H Deflection Circuit

TO:

180V

H Lin and

Ringing Circuit

12V

C575

FB506

5

R581

3

D518

Q521

T505

Q520

B+CHOP

R582

HST

3

C574

HDY-

4

HDY-

3

1

D516

L503

HOC

FB504

T504 HDT

1

H DY+

2

8

H DY+

1

1

2

6

TO: IC901 #32 pin

H FLY

Q508

D502

4

IC902 #14 pin

C521

C518

D506

R518

R517

R513

Q511

C522

Q507

H-OUT

C510

FB507

R522

R511

FB508

-15V

C543

R551

C563

20

3

R553

Out

H Reg

IN

H Def

IN

HD

PWM IC501

IN

H SHAPE

IC902

E/W PIN #9

8

2

R569

R584

R583

C582

- 10 -

C576

12V

12V

R504

R933

CN801

R509

C502

Q501

R594

Q903

HD output pin #17

IC902

R508

D501

Q502

1

8

2

3

4

5

6

1

2

4

3

1

2

3

1

2

3

4

5

6

7

C

6

7

0

C

6

7

1

C

6

7

2

C

6

7

3

C

6

7

5

C

6

7

6

C

6

7

7

D

6

3

3

D

6

3

4

D

6

3

5

D

6

3

6

I

C

6

1

0

I

C

6

1

1

L

6

0

7

P

H

6

0

1

R

6

3

0

R

6

3

1

R

6

3

2

R

6

3

4

R

6

3

9

R

6

4

1

R

6

5

1

T

6

0

2

*

*

*

*

*

*

*

*

*

*

*

*

P

O

W

E

R

S

U

P

P

L

Y

C

O

N

T

R

O

L

I

C

*

E

R

R

O

R

A

M

P

*

*

C

O

N

T

R

O

L

*

*

*

*

*

*

*

*

S

R

T

D

F

S

M

C

A

B

+

6

.

5

V

To SW 602

USB/Audio Power Circuit

A voltage clamp to limit the peak voltage on DRAIN pin 7 is provided by D635 and D636. Bypass capacitor C677 is
utilized to improve high frequency noise immunity.

IC610 provides the following protection functions: a 10mS soft-start function, a cycle-by-cycle peak current limit func­tion, a shutdown/auto-restart function if an out of regulation condition occurs and an over temperature protection function.

D BOARD DEFLECTION SECTION

1. Horizontal Deflection Circuit

Overview

These circuit drive the DY (Deflection Yoke) for Horizontal Deflection. The H size and H shape control (IC501 and around)
is included in this page as well.

H Drive, H Out, Feedback

+12Vp-p HD pulse is generated by the inverter Q903 using the Jungle IC902 H. out pin #17. And switch Q511 through A
push-pull amplifier (Q501 and Q502) buffers. The drive current which introduced in HDT (T504) by this switching will
drive Q507 (H out Tr) and 1000V pulse appears on collector. D506 is the "Damper Diode" which avoid the negative pulse
and discharge the energy for next Horizontal Drive. Q508 is the buffer for the "H BLK" feed back to Jungle IC 902 H. FLY
pin #14 and it will be the reference of phase / jitter control of Jungle. HST (T505) is to sense the deflection current
through DY. The voltage appeared on secondary side will be the feed back for H Size/Shape control.

H Size/Shape control

HD pulse also triggering the H Size/Shape control IC501 pin #8. IC501 is "PWM IC" and it controls H and HV B+
chopper duty. H Shape and H size information is already included and coming from Jungle IC902 E/W pin #9. It will be
supplied to IC501 pin #2. H reg output pin #20 is switching pulse of Q520 (B+ chopper). The energy supplement from
180V to H Def circuit (through L503 HOT) is controlled by the duty of this pulse. The H Shape input and feedback
voltage from T505 are compared by error amp (in IC501) and H Reg out pulse duty is controlled to keep the level of
these two the same.

- 11 -

H

6

m

0

2

8

5

.

7

L

2

5

3
5

&

1
0

2

9

5

C

,

I

1
5

M

,

O

0

R

5

F

,
9
4

S
N
I
P

0

C

1

C

5

H

L

7

8

1

+
Y

O

D

T

H

V
2
1

5

6

6

0

U

2

7

5

0

0

4

R

2

3

L

5

N

D

1

1

0

D

3

P

k

9

I

7

8

H

.

5

C

4

R

:

1
9
5
R

5

W

T

0

E

S

5

N

H

T

5

4

S
P

U
0

1

W

K
A

1

7

2

3

5

0

Q

1
A
S
2

D
T
5

2

2

1

-

5

9

D

1
1
S
S
1

W

0

N

4

5

R

/

1

:

1

3

2

9

0

2

3

2

2

7

L

/

5

5

4

1

R

N

D

W

1

S

D

P

0

C

k

9

-

2

5

N

2

R

R
:

1

7

T

0

1

P

.

5

:

0

C

6

W

0

N

1

4

5

R

5

/

1

:

R

1

2

W

N

0

9

4

5

R

5

/

:

1

R

1

5

4

1

4

1

#

0
9

N

C

I

I

P

N
I
L
H

R

2

E

W

0

0

2

T

0

5

/

1

N

V

1

R

E
C

H

3
0
0
P
L
C

H
m
2
.
2

5
0
5
L

R

7

V

9

P

4

0

2

P

0

5

0

:

.

C

4

0

7

5

V

P

4

0

2

P

0

5

0

:

.

C

4

0

2

V

3

1

1

P

8

0

2

3

.

P

0

5

5

5

0

:

.

2

C

C

0

V

7

6

P

1

0

2

P

5

5

.

:

2

0

C

P
P
:

V
0

8

0

6

4

5
C

7
4
0
.
0

D

W

5

0

2

R

7

2

7

0

7

P

.

/

5

1

5

F

4

1

R

C

:

V

2

4

P

A

8

0

1

P

T

5

.

5

:

1

0

2

-

C

1

0

5

4

D

L
N
1
D

5

P

k

8

I

2

2

H

P

.

5

C

1

6

I

2

R

:

0

0

H

.

5

C

0

C

:

A
1

9

1

1

6

T

W

0
5
T

6

3

5

C

E

3

Q

L

N

C
S
2

5

7

7

S

0

W

7

R

0

3

5

:

1

R

p

1

V

0

8

k

0

5

1

2

C

2

8

C

W

0

L

E

5

N

H

L

U
0

5

2

0

L

5

N

D

1
D

O
T

0

1

­Y
D

H

3

2

1

V
2
1

B

W
S

P

2

I
H

-

C

V

:

0

B

7
2

1
.
0

E
T

8

9

5

0

0

5

5

5

3

C

D

S
S
1

P

k

1

6

I

8

7

H

.

5

C

6

R

:

4

N

9

1

R

3

5

:

R

k

5

k

6

N

N

0

6

0

0

R

R

3

5

3

5

:

:

3

R

3

R

R
Q

P

-

M

4

A

A

0

1

5

5

4

F

k

Q

0

9

0

D

5

1

3

.

R

C

V
S
2

V
2
1

2

2

1

0

#

9
C

N

I

I
P

V.DF

2
0
5
R

V

3

2

7

0

7

k

N

.

3

5

5

W

0

S

2

R

0

/

:

1

1

V
5

Y
B
T
S

V

P

0

P

5

:

2

D

5

R

k

2

P

1

5

F

R

:

P
P
:

V
0
5
2

5
1

P

.

P

0

:

0

V

3

0

5

5

C

2

8
6
0
.
0

V

1

0

1

5

5

2

C

2

7

1

.

5

4

R

4

7

p

V

4

0

0

0

B

3

0

5

3

5

C

P

k

1

C

0

0

-

0

5

N

2

C

R
:

1
0
5
R

R

6

2

5

2

C

5

:

R

E
G

2

N

3

6

A

S

3

1

H

3

5

C

K

Q

S

P

2

A
C

D

6

R

k

3

P

1

5

F

R

:

5

k

3

6

5

5

R

D

3

R

k

3

P

1

5

F

R

:

3

k

2

6

5

5

R

4

k

2

6

5

5

R

D

1

R

k

2

P

1

5

F

R

:

5

k

1

1

5
R

3

S

P

1

8

I

0

3

H

.

5

C

0

C

:
B

0

S

N
R
:

E
G

2

N

S

3

A

5

3

H

1

3

C

5

K

Q

S

P

2

A
C

S

P

1

6

I

0

3

H

.

5

C

0

C

:
B

1

S

N
R
:

E
G
N

8

S

A

9

2

H

0

1

C

2

5

K

Q

P

S
2

A
C

P

S

1

0

I

0

2

H

.

5

C

0

C

:
B

2

S

N
R
:

E
G

S

8

N

9

3

A

0

1

H

2

5

C

K

Q

S

P

2

A
C

S

P

1

5

I

0

1

H

.

5

C

0

C

:
B

9

M

1

1

5
R

S

4
1
5
Q

P

1

2

I

0

1

H

.

5

C

0

C

:
B

D
R

7

P

0

F

5

:

C

2

5

T

3

S

1

B

#

F

N

O

I

T

P

E
G

8

N

9

A

0

H

2

C
K
S

P
2

A

C

)

S

8

5

3

1

5

(

R

W
J

4

S

8

V

1

0

.

0

0

4

1

T

3

F

0

D

5

:

T

8

1

F

V

7

p

k

5

0

2

1

C

5

V

p

0

k

0

5

1

2

C

k

7

N

7

0

R

.

5

:

P

2

R

1

3

I

0

0

H

.

5

C

0

C

:
B

7

R

3

5

E

0

0

F

1

5

F

A

Q

U

S

B

2

P

3

C

k

0

0

-

0

1

5

N

1

R

R

0
0
1

:

(BOARD)

D

H. LINEARITY AND RASTER DISTORTION CORRECTION CIRCUIT

- 12 -

H

6

m

0

2

8

5

.

7

L

2

5

3
5

&

1
0

2

9

5

C

,

I

1
5

M

,

O

0

R

5

F

,
9
4

S
N
I
P

0

C

1

C

5

H

L

7

8

1

+
Y

O

D

T

H

V
2
1

5

6

6

0

U

2

7

5

0

0

4

R

2

3

L

5

N

D

1

1

0

D

3

P

k

9

I

7

8

H

.

5

C

4

R

:

1
9
5
R

5

W

T

0

E

S

5

N

H

T

5

4

S
P

U
0

1

K
A

1

7

2

3

5

0

Q

1
A
S
2

D
T
5

2

2

1

-

5

9

D

1
1

6

S

1

S

5

1

R

W

0

N

4

5

R

/

1

:

1

3

4

2

9

0

2

3

2

7

L

5

5

4

R

N

D

W

1

S

D

P

0

C

k

9

-

2

5

N

2

R

R
:

1

7

T

0

1

P

.

5

:

0

C

W

0

N

4

5

R

/

1

:

1

2

W

N

0

9

4

5

R

5

/

:

1

R

1

5

1

4

1

#

0
9

N

C

I

I

P

N
I
L
H

R

2

E

W

0

0

2

T

0

5

/

1

N

V

1

R

E
C

H

W
2
/
1

3
0
0
P
L
C

H
m
2
.
2

5
0
5
L

R

7

9

V

P

4

0

2

P

0

5

0

:

.

C

4

0

7

5

V

P

4

0

2

P

0

5

0

:

.

C

4

0

2

V

3

1

1

P

8

0

2

3

.

P

0

5

5

5

0

:

.

2

C

C

0

V

7

6

P

1

0

2

P

5

5

.

:

2

0

C

P
P
:

V
0

8

0

6

4

5
C

7
4
0
.
0

D

W

5

0

2

R

7

2

7

0

7

P

.

/

5

1

5

F

4

1

R

C

:

V

2

4

P

A

8

0

1

P

T

5

.

5

:

1

0

2

-

C

1

0

5

4

D

L
N
1
D

5

P

k

8

I

2

2

H

P

.

5

C

1

6

I

2

R

:

0

0

H

.

5

C

0

C

:

A
1

9

1

1

6

T

W

0
5
T

6

3

5

C

E

3

Q

L

N

C
S
2

5

7

7

S

0

W

7

R

0

3

5

:

1

R

p

1

V

0

8

k

0

5

1

2

C

2

8

C

W

0

L

E

5

N

H

L

U
0

5

2

0

L

5

N

D

1
D

O
T

0

1

­Y
D

H

3

2

1

V
2
1

B

W
S

P

2

I
H

-

C

V

:

0

B

7
2

1
.
0

E
T

8

9

5

0

0

5

5

5

3

C

D

S
S
1

P

k

1

6

I

8

7

H

.

5

C

6

R

:

4

N

9

1

R

3

5

:

R

k

5

k

6

N

N

0

6

0

0

R

R

3

5

3

5

:

:

3

R

3

R

R
Q

P

-

M

4

A

A

0

1

5

5

4

F

k

Q

0

9

0

D

5

1

3

.

R

C

V
S
2

V
2
1

2

2

1

0

#

9
C

N

I

I
P

V.DF

2
0
5
R

V

3

2

7

0

7

k

N

.

3

5

5

W

0

S

2

0

R

/

1

:

1

V
5

Y
B
T
S

V

P

0

P

5

:

2

D

5

R

k

2

P

1

5

F

R

:

P
P
:

V
0
5
2

5
1

P

.

P

0

:

0

V

3

0

5

5

C

2

8
6
0
.
0

V

1

0

1

5

5

2

C

2

7

1

.

5

4

R

4

7

p

V

4

0

0

0

B

3

0

5

3

5

C

P

k

1

C

0

0

-

0

5

N

2

C

R
:

1
0
5
R

R

6

2

5

2

C

5

:

R

E
G

2

N

3

6

A

S

3

1

H

3

5

C

K

Q

S

P

2

A
C

D

6

R

k

3

P

1

5

F

R

:

5

k

3

6

5

5

R

D

3

R

k

3

P

1

5

F

R

:

3
2
5
R

4

k

2

6

5

5

R

D

1

R

k

2

P

1

5

F

R

:

5
1
5
R

3

S

P

1

8

I

0

3

H

.

5

C

0

C

:
B

0

S

N
R
:

E
G

2

N

S

3

A

5

3

H

1

3

C

5

K

Q

S

P

2

A
C

S

P

1

6

I

0

3

H

.

5

C

0

C

:
B

1

S

k

N
R

6
5

:

E
G
N

8

S

A

9

2

H

0

1

C

2

5

K

Q

P

S
2

A
C

P

S

1

0

I

0

2

H

.

5

C

0

C

:
B

2

S

N
R
:

E
G

S

8

N

9

3

A

0

1

H

2

5

C

K

Q

S

P

2

A
C

S

P

1

5

I

0

1

H

.

5

C

0

C

:
B

9

M

1

1

5
R

S

4
1
5
Q

P

1

2

I

0

1

H

.

5

C

0

C

:
B

D
R

7

k

P

0

1

F

5

:

C

2

5

T

3

S

1

B

#

F

N

O

I

T

P

E
G

8

N

9

A

0

H

2

C
K
S

P
2

A

C

)

S

8

5

3

1

5

(

R

W
J

4

S

8

V

1

0

.

0

0

4

1

T

3

F

0

D

5

:

T

8

1

F

V

7

p

k

5

0

2

1

C

5

V

p

0

k

0

5

1

2

C

k

7

N

7

0

R

.

5

:

P

2

R

1

3

I

0

0

H

.

5

C

0

C

:
B

7

R

3

5

E

0

0

F

1

5

F

A

Q

U

S

B

2

P

3

C

k

0

0

-

0

1

5

N

1

R

R

0
0
1

:

(BOARD)

D

(17VC H. CENTERING CIRCUIT)

- 13 -

Troubleshooting

See attached FLOW CHART and confirm if its really an H Deflection issue.

No H Deflection / No Power

Check Q507, Q520 and D506 first. In case any of these shorted, check T504, Q511, R511 and D502.
Those parts might have been damaged.
If both of Q507, 520 were not broken, check the HD pulse at the gate of Q511.
If no pulse, check Q501, Q502, Q903.
Otherwise, check R582, D518 or try changing IC501.

Bad Distortion

Check pin#2 of IC501 and confirm that proper DC level and AC waveform.
If the distortion is on only right side, check all above (No H Deflection).
Otherwise, refer to the Troubleshooting of next section (H Lin and Ringing Correction).

2. H Linearity and Raster/Distortion Ringing Correction Circuit

This section includes HLC Control circuit, S cap switching and HLC/S-Cap Damping circuits. These circuits are placed
directly on the cool side of DY which is in series with deflection current line. H Centering circuit will be explained in
next section.

HLC Balance Control and HLC Damping

HLC (L508) effectiveness is changed by LCT (T506) for each fH since T506 and L508 are in parallel. LCT is the Cross
Transformer that can change its inductance accordingly to the DC current of the secondary side. The current of the
secondary side is controlled by the DAC output of Micro (IC901 - pin 4) through Q519. It can be changed by the register
"HLIN_BAL_LOFH", "HLIN_BAL_MDFH" and "HLIN_BAL_HIFH". D505, C581 and R577 make up the damping
circuit to avoid Raster Ringing (mainly on the left side of the picture) caused by HLC, DY and S-caps.

S-Cap switching and S-cap Damping

H Def current is distorted by resonance between S-Cap and DY to correct the linearity. Since the resonance frequency
has to be changed for each fH, S-Cap switching is controlled by MICRO
S-Cap Switch - FETs (Q512, Q513, Q514, Q515, Q516) are "On" when its gate is Hi(5V) and that moment, drain voltage
should be grounded (0V).

L506, R578 and C573 is damping circuit to avoid Distortion Ringing (mainly on top of the picture) caused by S-caps and
H Control loop gain. L505, R575 and C572 is also the same purpose as above but only works when Q514 (Switch for the
Biggest S-Cap) is On.

Troubleshooting

See attached FLOW CHART and confirm if its really H lin issue.

Bad Linearity

Confirm that Raster is approximately in the center of the Bezel. If not, refer to next section (Raster Centering Circuit).
Check S-cap switches (Q512, 513, 514, 515, 516, HLC switch (Q519)) and confirm that H Linearity changes propor­tional to the value of S-Cap DAC. Confirm that H.LIN BAL changes by the register value of "HLIN_BAL_LOFH",
"HLIN_BAL_MDFH" and "HLIN_BAL_HIFH". If not working, check Q519, C508 or T506.

Bad Top Distortion/ Left side Raster Ringing

Check damping circuits explained above.

3. H. Raster Centering Circuit

Overview

H center circuit is changed from D99 type in which the Power OP-Amp is used

H Center Circuit

H Centering is changed by rotating RV502 to change the current through HCC (L510). Micro is no longer controlled.

Troubleshooting

See attached FLOW CHART and confirm if its really H Center Circuit issue.

No Raster Centering Control

Check R526, R529 and L510 first. Then, check D530, and D531. If these parts are good, check RV502.

- 14 -

#1, 2 PIN

Rotation Coil (CN701)

R563

R562

Rotation/Vertical Key Circuit

STBY

5V

R558

+15V

IC502

C549

5

V+

1

+

V-

-

2

3

4

R559

R560

C547

ROTATION

3

IC901

R566

-15V

C513

4. Rotation Circuit

Rotation is a PWM waveform at approximately 125kHz measuring 5Vp-p at pin #3 of the micorprocessor IC901. Then
filtered by R560 and C547 combination. The DC current is output by powered OP-amp (IC502). The output current from
pin #4 of IC502 flows through R563 and the rotation coil and returns to ground through R566. The feedback is sensed at
R566 and sent back to the amplifier through R562.

No Rotation Control

Check the waveform pin #3 of microprocessor IC901 if it is 5Vp-p PWM and approximately 125kHz. Otherwise, check
around IC502.

5. Dynamic Focus Circuit

Overview

Both H and V Dynamic Focus are combined through DFT (T503).

H DF

Horizontal Parabola is injected into the secondary side of the focus transformer (DFT:T503). In order to keep the amount
of parabola constant over the horizontal frequency range the values of the AC coupling capacitors are changed by the
transistors, which switch the s-caps. This signal is amplified by the turns-ratio to the primary side of the transformer.

V DF

V DF waveform is buffered by Q505 and amplified by Q504 to about 130Vp-p. VDF is controlled by Jungle IC902 pin #12.
300v Vcc is made by FBT through D515. This voltage is also used for HV Protector.

Troubleshooting

See attached FLOW CHART and confirm if it is really a DF issue.

Bad H DF

Check H. Linearity. If there is no problem, change T503 (DFT).

Bad V DF

Confirm that waveform is around 1Vp-p from Jungle pin 12 of IC902. If its more than 2.0Vp-p, change Jungle IC902.
Check 300v from FBT.

- 15 -

+
Y

O

D

T

H

Dynamic Focus Circuit

7

0

7

0

5

1

R

p

1

V

0

8

k

0

5

1

2

C

2

H

6

m

0

2

5

.

L

3
5

&

1
0

2

9

5

C

,

I

1
5

M

,

O

0

R

5

F

,
9
4

S
N
I
P

0

C

1

C

5

H

L

7

8

1

V
2
1

5

6

R

2

6

U

2
5

0

0

R

2

3

L

5

N

D

1

1

0

D

3

P

k

9

I

7

8

H

.

5

C

4

R

:

1
9
5
R

5

W

T

0

E

S

5

N

H

T

5

4

S
P

U
0

1

K
A

1

7

2

3

5

0

Q

1
A
S
2

D
T
5

2

2

1

-

5

9

D

1
1

6

S

1

S

5

1

R

W

0

N

4

5

R

/

1

:

1

3

4

2

9

2

3

2

L

5

5
R

N

D

W

1

S

D

P

0

C

k

9

-

2

5

N

2

R

R
:

1

7

T

0

1

P

5

.

:

0

C

W

0

N

4

5

R

/

1

:

1

2

W

0

9

4

5

5

/

1

R

1

5

1

E

W

0

0

0

2

T

7

0

5

/

1

4

N

V

1

R

E
C

H

W

0

2

7

/

4

1

3
0
0
P
L
C

N
R
:

2

7

9

V

P

4

0

2

4

P

0

5

0

1

:

.

#

C

4

0

0

9

N

C

I

I

P

N
I
L
H

7

5

V

P

4

0

2

P

0

5

0

:

.

C

4

0

V

3

1

P

0

2

.

P

5

5

0

:

2

C

V

7

6

P

1

0

2

P

5

.

5

:

2

0

C

P
P
:

V
0

8

0

6

4

5
C

7
4
0
.

0
H
m

D

5

W

0

2

R

7

2

0

.

P

5

/

1

2

F

R

1

:

5
0
5
L

V

2

4

P

8

0

1

P

5

.

5

:

0

2

C

5

P

k

8

I

2

2

H

P

.

5

C

1

6

I

2

R

:

0

0

H

.

5

C

0

C

:

A
1

9

1

W

1

6

T

W

3

0

C

E

5

L

N

T

6

7

S

W

R

3

:

8

C

W

0

L

E

5

N

H

L

U
0

5

2

0

L

5

N

D

1
D

O
T

0

1

­Y
D

H

S

5

3

Q

C
S
2

5

P
I
H
C
:
B

1
.

3

0

9
0
5
C

2

1

V
2
1

B

P

k

1

6

I

7

8

H

5

.

C

6

R

:

4

N

9

1

R

3

5

:

R

k

5

k

6

N

N

0

6

0

0

R

2

5
R

­V
0
7
2

E
T

8

5

0

5

5

3

D

S
S
1

V
2
1

2
1
#

N
I
P

R

3

3

5

:

:

3

3

R

R
Q

P

-

M

4

A

A

0

1

5

4

F

Q

9

D

3

.

C

V
S
2

2
0

V.DF

9
C
I

3

V

2

7

7

0

k

N

.

3

5

5

W

8

0

S

C

7

2

0

R

5

/

1

:

1

R

6
3

V

5

5

R

Y
B
T
S

3
3
5
R

2

V

1

P

8

0

3

P

0

5

5

:

.

2

C

0

D

5

R

k

2

P

1

5

F

R

:

P
P
:

V
0
5
2

5
1

P

.

P

0

:

0

V

3

0

5

5

C

2

8
6
0
.
0

1

V

2

7

1

2

0

7

.

1

5

5

5

4

5

R

2

C

C

A
T

1

-

1

0

5

4

D

L
N
1
D

2

7

1

.

5

4

R

3

4

7

8

p

V

4

0

0

0

B

3

0

5

3

5

C

5

k

0

0

5

1

R

P

k

2

1

C

0

0

0

-

0

5

5

N

2

R

C

R
:

1
0
5
R

R

6

2

5

2

5

:

R

E
G

2

N

3

6

A

S

3

1

H

3

5

C

K

Q

S

P

2

A
C

D
R

k

P

1

F
:

5

k

N

3

6

R

5

5

:

R

D
R

k

P

1

F
:

3

k

2

6

5

5

R

4

k

N

2

6

R

5

5

:

R

D
R

k

P

1

F
:

5

k

1

1

5
R

3
0

5
C

0
1

0
0
1

S

P

1

8

I

0

3

H

.

5

C

0

C

:
B

0

S

E
G

2

N

S

3

A

5

3

H

1

3

C

5

K

Q

S

P

2

A
C

S

P

1

6

I

0

3

H

.

5

C

0

C

:
B

1

S

N
R
:

E
G
N

8

S

A

9

2

H

0

1

C

2

5

K

Q

P

S
2

A
C

P

S

1

0

I

0

2

H

.

5

C

0

C

:
B

2

S

E
G

S

8

N

9

3

A

0

1

H

2

5

C

K

Q

S

P

2

A
C

S

P

1

5

I

0

1

H

.

5

C

0

C

:
B

9

M

1

1

5
R

S

4
1
5
Q

P

1

2

I

0

1

H

.

5

C

0

C

:
B

D
R

7

P

0

F

5

:

C

1

2

1

F

V

7

p

k

5

0

2

1

C

5

V

p

0

k

0

5

1

2

C

k

7

N

7

0

R

.

5

:

P

2

R

1

I

0

H

.

C

0

:
B

7

R

3

5

E

0

0

F

1

5

F

A

Q

U

S

B

2

P

3

C

k

0

-

0

5

N

1

R

R
:

5

T

3

S

1

B

#

F

N

O

I

T

P

E
G

8

N

9

A

0

H

2

C
K
S

P
2

A

C

)

S

8

5

3

1

5

(

R

W
J

4

S

8

V

1

0

.

0

0

4

T

3

F

0

D

5

:

T

- 16 -

6. High Voltage Protect Circuit

This circuit generates the High Voltage supply for the anode. It consists of a high voltage driver and regulator similar to a
switching power supply function. In addition, there are High Voltage and Beam Current protection circuits. All those
circuits are similar to D99 chassis circuits.

High Voltage Regulation and Output Circuit

The HV Drive pulse is generated by IC501 and synchronized with Horizontal drive pulse. It is supplied to the Gate of Q510
the HV Out FET.

The HV Out Pulse approximately 700V, is generated by Q510 switching with the peak voltage being controlled by the
switching duty of Q503 (B+ chopper). Internal resistors and R540 and RV501 divide HV generated in the FBT. Since this
voltage is the feedback for HV Regulation control. Adjusting RV501 will result in changing the HV Regulation level(= HV
level). HV Feedback voltage is returned to IC501 at pin#12 to be compared with an internal reference voltage of IC501 at
pin#13. According to this feedback level, IC501 changes the pulse duty cycle. This pulse is felt at pin #18 of IC501 thereby
controlling the output of B+ chopper drive Q503.

G1 Voltage (-33Vdc)

D510 and C528 through R532 rectify -57Vdc developed by a -57V winding of FBT. It is then regulated by D503 and C533
to be -33Vdc typ through R539. -33Vdc is supplied through R570 to the A Board via CN510.

HV Protect Circuit

HV Protect circuit will be activated by the Microprocessor when the signal at HV DET, Microprocessor pins#18 reaches a
+5vdc level. HV DET indicates the level of the primary current developed by the 270V winding of the FBT through R543,

D515.

Beam Current Protect

Beam Current Protect will be activated when ABL DET at microprocessor pin#16 reaches a level of 0V when operating in
main mode. ABL DET level is corresponding to the Beam Current which is supplied to FBT through R596, R550 and R548.
The voltage current relationship is inversely proportional Voltage (down) Current (up).

Troubleshooting Hints

See attached FLOW CHART to confirm if is really an HV/Protect Circuit issue.

No HV / No Power

Perform basic checks of Q510 and Q503 first. If both Q510 and Q503 were not broken, check the HV Drive pulse at the
gate of Q503. If no pulse, check R534 and D509. Otherwise, check R520, D504 or try changing IC501.

No G1 Voltage

Check R532, D503 and D510

Protect Malfunction

To see if HV Prot or ABL Prot are suspect check the Shutdown Log data at the Shutdown Log register. Refer to Shutdown
Log Table below.
When an HV Shutdown is indicated, check R917, R921, R543, D515 and D517 or, replace T501 (FBT).
Where ABL Shutdown is indicated, check the voltage T901 pin#11.
If it is higher than 0.5v immediately prior to shutdown. Should the voltage reach and remain at the 0 volt level, even after
the first 2.0 seconds of Power On, check D514 or check White Balance.

SHUTDOWN LOG TABLE

Bit Register value Shutdown Mode Comment

bit7 128 N/A N/A
bit6 64 N/A N/A
bit5 32 S Cap Shutdown Explained later
bit4 16 ABL Shutdown Hardware Controlled
bit3 8 HV Over Hardware Controlled
bit2 4 HV U Shutdown Not Used
bit1 2 No Vertical Scan Explained later
bit0 1 No H Scan Explained later

- 17 -

"

2

K

1

C

#

A
B

N

D

I

E

P

E
F

1
0

V

5

H
"

C
I

P
I

p

6

H

0

5

C

2

5

:

2

C

H
C

V

1

9

8

k

6

7

5

4

R

1

N

k

4

R

1

5

:

R

0
4
5
R

4
3
5
C

V
H

131

k

4

0

0

3

0

4

0

.

5

7

5

0

1

C

2

R

1

k

0

0

5

0

V

1

R

k

N

0

R

0

:

2

7

M

9

2

5

.

R

2

2

N

k

4

R

1

5

3

:

V

R

3

0

0

0

.

1

0

2

V

2

2

0

3

.

0

5

0

1

C

6

T

1

W

B

0

E

F

5

N

:

T

T

T

U

U
O

O

F

F
D

D
&
H

H

A

V

D

I

F

A

V

E

K

L

T

L

R

B

C

1
0
5
G

1
V
F

S

V

5
1

4
1

S

V
2
1

2
V
F

6
1
#

6

k

N

2

9

R

5

.

:

1

R

k

0

N

2

5

R

.

5

:

1

R

8

k

N

2

4

R

.

5

:

R

1

1

N

0

I

9

P

C

T

I

E
D

L
B
A

1

7

4

.

5

4

C

P

5

C

k

4

-

7

5

N

4

R

R
:

6

k

N

4

R

3

5

3

5
3
5
C

1
1

:

R

1

T
P

.
0

:

2

4

8

1

S

5

S

D

H

2
1

2

P
F

T

0

0

U

8

1

O

B

5

N

Q

V

4

H

P
T
S

0
2
5

p

6

V

0

2

0

0

5

0

2

5

C

2

0

S

W

2

3

R

3

8

5

:

R

1

S

W

2

6

R

3

8

5

:

R

1
3
5
R

3
0
5
B
F

.

9

G

3

4

E

0

4

R

5

J

S

Q

S

V

2

H

2

7

2

7

4

/

V

5

.

1

R

0

0
8
1

4
2
5
C

R

S
R
:

W
3

2

2

0

8

5

1

L
0
5
L

0

3

4

1

L

5

N

0

D

1
D

1

V

7
2

0

0
5

5

.

2

C

0

D

4

9

0

R

3

0

0

P

5

5

1

F

7

R

k

D

:

2

0

5

1

R

V

3

0

3

0
2

9
1
#

N
I
P

E
V
I
R
D

V
H

1

7

p

9

P

V

0

1

P

k

0

5

:

2

2

C

1

S

1
T

-

4

A

0

2

5

1

D

D
C
N

4

k

N

7

2

5

.

D

0

R

2

R

0

P

1

F
:

2
0

0

5
B
F

1
0
5

C
I

D

3

7

R

4

.

P

5

4

F

R

:

2

­V
0
7
2

7

k

N

4

0

R

5

2

:

R

2

5

k

N

9

0

R

5

2

:

R

2

9
1
#

N

1

I
P

E
V
I
R
D

V
H

E

0

T
2

5

7

0

1

-

5

C

3

D

I

3
T
Z
H

2

N

k

5

R

6

5

:

5

R

8
1
#

1

N

0

I

9

P

C

T

I
E
D

V
H

4

6

2
3
5
R

U
0

0

4

1

L

5

N

D

1
D

9
3
5

E

R

T
2

3

0

0

-

5

3

D

3
T

1

Z

P

H

T

5

0

1

1

5

-

D

4
3
A
R
E

V

0

1

4

0

0

5

.

3

C

0

6

2

V

0

4

0

1

5

5

C

0

k

9

N

N

k

1

1

4

R

R

2

5

.

5

:

:

6

R

9

R

1

4

T

0

4

P

.

5

:

0

C

3

D

2

R

.

P

2

F
:

1

V

8

T

0

2

0

P

.

0

5

:

2

C

0

N

k

R

0

:

1

3

0

V

3

.

0

5

1

5

C

8

5

E

W

0

G

k

2

7

R

0

/

5

U

1

1

R

S
:

0

9

1

D

3

R

#

A
O

N

B

I
P

A

1

O

0

T

0
J

1
G

(BOARD)

D

17VC CHASSIS HV/PROTECTOR CIRCUIT

- 18 -

+15V

R412

C411

C404

2

IC 701

(CONV)

5

Vref

R410

0

7

C409

R409

IC 902

(Jungle)

8

R406

VSAW

C410

Vertical Deflection Circuit

6

C403 D401

IC401

Flyback Generator

3

+

-

V-

V+

R413

R401 C402

541

LVDY

LA78040

RL

V-DY through CN501

-15V

R402

C401

R404

0

C406

D-BOARD

R405R403

0

- 19 -

G1, Heater and Focus Voltages from D Board

Front Input

Video

Process

D/A Conv

RGB Cathode Drv

D/A Level

J

0

0

1

CRT

2

I

C Communication

H and V Retrace

OSD Generation

Cutoff

Voltage

Cutoff

G2 Voltage

From

FBT

17VC Chassis A Board Block Diagram

7. Protection Circuitry Overview

Overview

The 17VC chassis was developed with protection circuits other than HV/ABL.These protection circuits are controlled by
Microprocessor (IC901); All of these circuits are similar to the D99 Chassis.

 S Cap Shutdown: Activates when S-Cap Switch in FET are broken.
 V Scan Shutdown: Activates when Vertical Deflection signal is absent or of insufficient level or of a distorted nature.
 H Scan Shutdown: Activates when Horizontal Deflection signal is absent or of insufficient level or of a distorted nature.

Troubleshooting Hints

S Cap Switch Shutdown

In the event of failure of any S-Cap Switching FETs, and "POWER_SW" or AC Power Switch was turned off/on, the
microprocessor detects FET Gate damage and goes into shutdown mode. For these conditions, refer to the section of H
Linearity Circuit.

Vertical Scan Shutdown

If the V FLY feedback at pin #19 the Microprocessor doesn't get pulse around 1.5 second, a Shutdown will be initiated.
Power Supply problems may also produce a similar type failure. For these conditions, refer to the V Deflection Circuit
or the Power Supply section.

Horizontal Scan Shutdown

If the H FLY feedback at pin #32 of the Microprocessor doesn't get pulse around 500mSec, Shutdown will be initiated.
Some power Supply problems may also produce a similar type failure. For these conditions, refer to the H Deflection
Circuit or Power Supply sections.

8. Vertical Deflection Circuit

Theory of Operation

The negative input of amplifier IC401 is driven by VSAW signal generated by Jungle IC902 pin #8. The positive input of the
amplifier is Vref Signal generated by IC701 (Convergence IC) pin #5. VSAW is centered on 5. 0V, and sawtooth waveform
that controls VSIZE. Vref is a reference that is compared to VSAW at IC401. VCENTER is controlled by the shift of

- 20 -

Video Select and RGB Process Functions

10

8

9

11

IC004

IC002

10

13

+80V

6

D104

5

3

1

C306

D105

0

+B

11

7

8

9

R

G

C206

B

C106

CRT

D106

D206

D306

Video Input (0.7Vpp)

Board

From N

From IC003

R

G

B

2

I

C Data

2

C CLK

I

CBLK

BPCLP

R_OSD

B_OSD

B_OSD

OSD_BLK

18

11

1

2

12

15

14

13

17

+5V

9

7

IC001

+12V

16,22,298

+12V

20

24

27

D/A

Cutoff

Control

5

4

3

R

G

B

+12V

2

R

G

B

3

4

5

VSAW. IC401 serves as a transconductance amplifier (it amplifies a low level voltage into a high level current) for VSAW
and the DC difference between VSAW and Vref. The current gnerated by IC401 is feed to the Vertical Deflection Coil. At
the return point of the Vertical Deflection Coil the current flows through R403 and R405 which generates a voltage across
them which is feed back to the amplifier via R404.
V FLY is generated by flyback pulse generated at pin 3 of IC401. If the flyback generation at IC401 does not work, then the
monitor will go into shutdown as a V scan failure by the microprocessor after wait approximately 1.5 sec without VFLY.

Troubleshooting Hints

Vertical Scan Failure

The first step is to check the shutdown log of the monitor and make sure the microprocessor has detected a loss of VFLY.
Once this has been verified the output of IC401 should be checked. If a normal output exists after the "POWER_SW" is
turned on but the monitor still shuts down then the VFB detection circuit is malfunctioning. If no output exists signal
tracing should begin at IC902 pin #8 (VSAW) and IC701 pin 5 (Vref). In shutdown mode both of these levels should be

5.0V DC. If the "POWER_SW" is turned on a sawtooth waveform of about 1Vpk-pk should appear on VSAW while DCC
stays at 5.0V this should last about 1.5 seconds until a loss of VFLY is detected and the monitor shuts down again. If the
signals make it this far, the problem is likely in the IC401 area.

VIDEO "A" BOARD ELECTRICAL CIRCUIT

The Main function of the A Board is to receive incoming video signals and then process them into the RGB video drives
necessary for proper CRT biasing. The input signals (RGB) are received with the conventional 15 D-sub connector. The
RGB signals (0.7Vpp) are sent to the preamplifier (IC001) where they are amplified with Contrast gain and Brightness
offset. Next they are sent to the Video Driver for final amplication to drive the cathodes. IC003 is the On Screen Display
(OSD) generator. OSD mixing is performed in IC001. Additional functionalities of the A Board include processing of all
the CRT cathodes operating voltages; heater, G2, cathode DC bias, and focus.

 Sync on Green Buffering.
 RGB video signal amplification and adjustment according to white balance requirements, contrast and brightness

settings.
 On Screen Display mixing.
 D/A conversion for RGB CRT cathode cutoff levels control.

- 21 -

SDA(MOSI)

SCL(SCK)

SS

VFLB

RP

VCO

HFLB

DD(A

V

SS(A

V

V

DD

V

SS

Block Diagram IC003 OSD

7

DISPLAY

MEMORY

CONTROL

REGISTERS

7

8

6

MCLK

VPOL

10

CHS

VERD

CH

3

2

5

HPOL

4

)

1

)

16

8

6

DATA

RECEIVER

MBUS/SPI

RFG

BUS ARBITRATION

LOGIC

NROW

VERTICAL

CONTROL

CIRCUIT

R

K

L

O

C

H

M

D

HORIZONTAL

CONTROL

and PLL

SC CCLK

W

A

D

54

D

R

BACKGROUND

GENERATOR

8 DATA

9ADR

9 ADDRC

32 Y

R4

7

HORD

X32B

W

WCOLOUR

and CONTROL

and DATA

MANAGEMENT

RDATA

4

LP

3

15

Z

8

ROW

BUFFER

CRADDR

CHARACTER ROMS

HIGH RESOLUTION FONT 12 X 18

CHAR

12 BITS SHIFT

REGISTERS

E

N

C

E

N

_

A

D

N

S

I

O

M

U

L

COLOUR ENCODER

15 14 13 12 11

R

B

G

HORD

8

VERD

6

CH

OSD_EN

SHADOW

BSEN

X32B

VPOL

HPOL

54

WADDR

WCOLOUR

15

and

CONTROL

32

13

CCOLOURS

and SELECT

CHS

CWS

6

12

CWS

BSEN

SHADOW

E

G

D

E

CCOLOURS

K

and SELECT

C

A

L

B

G

K

B

F

13

T

N
I

GND

Block Diagram IC004 Cut-off Module

Video signal (R)

12 V

2

Vref

1

+B voltage

11

3

R-Cont in

R-bias out

7

G

b

l

o

c

k

Similar to R block

CRT cathode (R)

B

b

l

o

c

k

- 22 -

1. RGB Signal Processing (A Board)

RGB Signal Amplifiers

RGB video signals are amplified by IC001. Here the individual Sub Contrasts, Brightness offsets, and Contrast gain levels
are set by the Microprocessor via I2 C control. The OSD RGB video signals from IC003 are mixed into the main video
channels inside IC001. IC002 provides a final amplifier stage for the RGB video signals. This video driver is internally set
to a gain of 14. Therefore at the output pins of IC002 (Pin1, 3 & 5) the waveform is inverted with typical drives levels on
the order of 45Vpp. The Video Driver IC002 drives the CRT cathodes via AC coupling.

RGB Cathode Cutoff Amplifiers

The Red cathode DC cutoff level is amplified by IC004. It is controlled by the D/A output of IC001. The Red cutoff level
is clamped by discharging C106 via D106. The Green and Blue cathode Cutoff levels are clamped in a similar fashion. The
individual cathode cutoff levels are set for white balance by the Microprocessor via I2C communication with IC001.

Troubleshooting Hints

1) If the screen is blank with no output check:

 Video signals with proper cutoff levels are provided to the CRT cathodes.
 Supply voltages are at the appropriate levels and locations starting at CN304.
 Heater voltage is correct and present at the heater cathode.
 Diode shorts at the cathodes.
 There is I

2) If the screen is lighted with no video check:

 Control, blanking and clamp signals to IC001, IC002.
 +5V, +12V, and +80V to these circuits.
 For shorted diodes on the IC002 outputs.

2

C communication to IC001.

3) If colors are wrong or missing and white balance cannot be adjusted check:

 Each individual color signal path comparing DC offset and peak to peak signal levels to each other to determine

if there is any single amplifier at fault.
 For shorted diodes on the IC002 outputs.
 G1 level at the cathode (-33V)

2. On Screen Display Functions

On Screen Display(OSD)

IC003 is the On Screen Display character and graphic generator. It provides RGB and Fast Blanking data to IC001 for
mixing with the main video channels when required. Outputs voltages are two dimensional, either 0V or 5V. IC003 is
controlled by the Microprocessor via the I2C bus. The sync timings necessary are H Retrace and V Retrace.

Troubleshooting Hints

1) No OSD is displayed, check:

 RGB and Fast Blanking inputs to IC001. If there are no signals then IC003 may be at fault.
 That +5V is supplied to IC003
 V FLB and H FLB signals are at pins 10 and 5 of IC003 respectfully.
 That there is I2C communication to IC003.

3. G2

Troubleshooting Hints

1) If picture is black, check:

 G2 level at the cathode using HV probe (typically 350V ~ 750V).
 Input to G2 amp, Pin 5 of IC005.
 Heater voltage at the cathode.
 +12V, +5V, and G2 voltage coming from D board.

4. Display Data Channel (DDC) Circuit

DDC2B allows the display to inform the host computer of it's identity and capability. IC906, which has memory and I2C bus
serial communication capability, is a device for DDC2B. Pin 5 and 6 of IC906 are prepared for SDA (I2C data) and SCL
(I2C clock). EDID (Extended Display Identification Data) consists of 128 bytes of data containing the display's identity and

- 23 -

capability. This is written into the memory of IC906. The DDC compatible host computer reads the EDID using pins 12

A

and 15 of the VGA connector (see the table below regarding the contents of EDID and the VGA connector).

DDC2Bi allows the display to communicate more detailed data to the graphic host computer. IC901 is a micro-controller,
which contains DDC2Bi and I

2

C bus serial communication capability. Pins 34 and 35 of IC901 are prepared for SDA (I2C

data) and SCL (I2C clock). These are connected to pins 12 and 15 of the VGA connector shared with IC906

Troubleshooting Hints

1. If an error occurs in the DDC communication, the DDC compatible host computer indicates "unknown monitor", or the
available resolution will be minimized. Watch the pulses on the SDA and SCL to check to see if the DDC communica­tion succeeds. Knowledge of I2C bus serial communication is required to distinguish the error.

DDC Data Format and VGA Connector Allocations

Basic EDID consists of 128 bytes

Number Description Pin No.

8 Bytes Header 1 RED Video 11 Option

10 Bytes Vender/Product Identification 2 GREEN Video 12 Data (SDA)

2 Bytes EDID Version/Revision 3 BLUE Video 13 H SYNC

5 Bytes Basic Display Parameters/Features 4 Option 14 V SYNC

10 Bytes Color Characteristics 5 Return 15 Clock (SCL)

3 Bytes Established Timings 6 Red Return

16 Bytes Standard Timings 7 Green Return

72 Bytes Detailed Timing Description 8 Blue Return

1 Byte Extension Flag 9 Option +5V

1 Byte Checksum 10 Sync Return

15 pin VGA type connector

ssignment Pin No. Assignment

U BOARD: AUDIO CIRCUIT

IC1701 is the Audio Amplifier IC. It receives audio left and right signals through the audio input jack (J1702) and outputs
the amplified signals to the mono speaker and the stereo headphone jack (J1701). The amplitude level is controlled by
RV1701.

J1701 has a mechanical switch on it. If the headphone jack is connected, the signal line of the speaker is disconnected
(headphone = on; speaker = off). If the headphone jack is not connected, the output signal is provided to the speaker
(headphone = off; speaker = on).

IC1702 is a voltage regulator with a switch. It receives +6.5V from the stand-by power supply circuit and outputs +5V to
IV1701. When the monitor is in active off mode, IC1702 stops supplying VCC to IC1701 (audio function deactivated,
controlled by Micro, IC901).

Audio Circuit Block Diagram

2

0

7

1

C

I

E

G

A

T

L

O

V

R

O

T

A

L

U

E

G

R

V

+

V

5

.

+

6

W

S

R

E

W

P

O

Y

B

D

E

L

L

O

R

T

N

O

C

1

9

0

C

I

2

0

7

1

J

M

O

R

F

A

N

I

I

O

D

U

5

R

E

K

A

E

P

S

6

,

4

6

,

1

2

1

,

1

0

7

1

C

I

P

M

A

O

I

D

U

A

9

E

N

O

H

P

D

E

A

H

1

4

,

7

1

0

7

1

V

R

N

I

A

G

L

O

R

T

N

O

C

- 24 -

System Block Diagram

IN VIDEO

MAIN
AC

POWER SW

IN SYNC

DISPLAY DATA COMM BUS

JIG

I/O(RS232C)

D BOARD

HEATER

POWER SUPPLY

DC POWER

2

I

Deflection

PS Mode

(DDC)

C-BUS

SYNC PROC. &

CONTROL

VIDEO BLOCK

OSD

A-BOARD

Sync

-33V

FOCUS

BLOCK

FBT

I/O

RGB VIDEO

FOCUS/G2/G1
HEATER

STATIC/

DYNAMIC

FOCUS

G2

DEFLECTION

I/O

H & V

D.CONV

HV

H/V

DEF.

TILT

USER
CONT

H

BOARD

Alignment jig

(fac to ry,s er vic e)

PC

(Hos t com pu ter)

DDC

Digital Control Communication Diagram

VIDEO BOARD

EEPROM

IC905

I2C BUS

Micro

processor

IC1001

I2C-BUS

EEPROM

DDC IC

IC906

User conrol/

Power sw

IC905

JUNGLE IC

IC902

CONVERGENCE IC

A BOARD

IC701

Pre-AMP

IC0 0 1

OSD

IC0 0 3

BIAS

DRIVE

CONTRAST

BRIGHT

Info rm a tio n for US E R

SIZE,CENT

GEOM (PIN,KEY...)

CONV.(STAT,DYNAMIC)

D BO ARD

- 25 -

GENERAL TROUBLESHOOTING

Input crosshatch from generator

No Picture

Missing Color or Abnormal Color

Visible Retrace or Visible Raster

Mis-convergence

Poor Focus

A

B

C

D

E

Unsynchronized Image

Abnormal Geometry

Abnormal Image Size

Shutdown

No Communication

F

G

H

I

J

Other Trouble

See Manager

- 26 -

NO PICTURE

A

Is amber

power LED

blinking?

No

Is

amber LED

on?

No

Is

green

power LED

on?

Yes

Yes

I

Yes

Check the video

cable connection

No

Press power switch;

if LED does not turn

on, repair power supply (I)

Does

A-Board make proper

contact with

CRT gun?

Yes

Check heater, G2, red, green

and blue cathode voltage levels.

Repair video (12) if needed

Done

- 27 -

No

Press A Board carefully

to make proper contact with

CRT gun

No

Can

you get

picture?

Yes

MISSING COLOR

B

Check signal

generator &

cable

12

(See Parts Level Board

Repair Section)

Check IC004,

IC001 pins 3,

4, 5 and +B

voltage

No

No

No

Are

proper video

levels present

on CN302 pins

2, 4 & 6?

Ye s

Are

proper AC

voltages present on

all cathodes?

Ye s

Are

proper DC

voltages present

on all

cathodes?

Check CN301

and FBT

No

Ye s

Is

G2 voltage

correct?

Ye s

Change the

CRT

Done

- 28 -

VISIBLE RETRACE

C

Check white balance

adjustment

Check CN301

and FBT

Check

CBLK

signal at

IC901 pin

46

Check IC001

and related

components

No

No

No

Is

G2 voltage

correct?

Ye s

Is

blanking pulse

present on pin 18

of IC001 on

A-Board?

Ye s

Is

blanking pedestal

present in the waveforms

at pins 20, 24 &

27 of IC001?

Check IC002

and

IC004

No

Ye s

Is

blanking pulse

present on all

cathodes?

Ye s

Done

- 29 -

MISCONVERGENCE

D

Reset using

front panel control

Try adjusting convergence

using front panel controls

Ye s

Try adjusting convergence

using DAS

Is the convergence

within spec?

Yes

No

No

readjust convergence

Is the convergence

now within spec?

Check the convergence
circuit (IC701 & IC702

& IC703)

Change DY and

Is

convergence

within spec now?

Ye s

Ye s

Is the convergence circuit

(IC701, IC702, IC703)

OK?

Done

No

Repair &

adjust

No

Change CRT &

readjust convergence

Done

- 30 -

POOR FOCUS

E

Adjust

focusVRs

Age monitor
and check for
focus change

11

Ye s

No

Improved

focus?

No

Check focus leads

from FBT to CRT

socket

Check CRT socket

Is dynamic focus

circuit OK?

(See Parts Level Board

Repair Section)

Ye s

Replace CRT

and verify

focus

Done

- 31 -

UNSYNCHRONIZED IMAGE

F

Check input

signals CN903

pins 6 and 7 and

CN302 pin 4

Check video

cable

Check IC001

and related

components

Check wire

dressing and

connections

No

No

No

Are signals

correct?

Ye s

Signal at CN309

pin 8 OK?

Ye s

Signal at CN903

pin 8 OK?

Ye s

Check circuits on

D-board (IC901

and IC902)

Done

- 32 -

ABNORMAL GEOMETRIC DISTORTION

G

Download

factory settings

Identify distortion

problem and repair

(See Board Level Repair

Section)

No

Is geometric

distortion

correct?

Ye s

Done

- 33 -

ABNORMAL IMAGE SIZE

H

With user controls

adjust picture size

5

(See Parts Level Board

Repair Section)

4 or 5

(See Parts Level Board

Repair Section)

No

Ye s

Horizontal size

adjustment OK?

Ye s

Vertical size

adjustment OK?

Ye s

Adjust monitor

Done

- 34 -

SHUT DOWN

I

Check power

supply

Check horizontal, vertical

deflection system and

check power supply

secondary voltages

Check high

voltage system

No

Ye s

Ye s

Is amber

LED blinking?

Ye s

Check shutdown

log in IC901

Scan failure?

No

High voltage

failure?

10

(See Parts Level Board

Repair Section)

No

No

ABL OK?

Ye s

Set factory settings

inside IC901

Done

- 35 -

NO COMMUNICATION

J

Correct

connection

Correct settings
and connections

Check Connector

and power supply

No

No

No

Are connections

to monitor OK?

Ye s

Are computer

settings and

connections OK?

Ye s

Is 5 volts present

at CN901 pin 2?

Ye s

Check IC901 and

related components

Done

- 36 -

PARTS LEVEL BOARD REPAIR

Parts Level Board Repair

(1) Power Supply

(2) Horizontal Deflection

(3) High Voltage

(4) Vertical Deflection

(5) Horizontal Size

(6) Horizontal Center

(7) Key and Pin

(8) Key and Pin Balance

(9) Rotation

(10) ABL

(11) Dynamic Focus

(12) Video

(13) Convergence

(14) USB/Audio Power Supply

(15) Audio

- 37 -

Check F601, D601,

VA601, R600, TH600,

Q602, R651, IC610

No

Check F601

and D601

Is C610 DC

rail voltage correct?

POWER SUPPLY

1

D608, R605, R614,

R657, R654, R623, R624,

R612, R603, C650, and

Are F601,

IC601 OK?

No

Replace parts,

verify voltages

Check R627, Q503

Q507, Q510, Q520,

and video board.

Check for overload

on IC607

Check IC602, IC603,
D605, C650, Q503, Q507,
Q510, Q520, Q604, R614,

R623, R624, R627, R654,

R657, C650. Check for

overload on IC607. Check

front panel power button

Replace Q602,
Check F601, C650,
IC601, D608, R603,

R605, R612, R614,
R623, R624, R654,

and R657

Ye s

Ye s

No

Ye s

Does power

supply make

chirping noise?

No

Tries to start?

No

Is Q602 OK?

Ye s

Ye s

Check secondary diodes,

R627, IC501, IC901, IC902,

IC605, IC401, IC607, IC608

Operating?

Ye s

Verify voltages and

adjust monitor

No

OK, replace D board

Check A board; if

Check D623, D625,

C614, R602, R613,
R615, R616, R693,

and S602

No

Is IC601

pin 14 > 2.8V?

Ye s

Done

- 38 -

HORIZONTAL DEFLECTION

2

Check IC901 and

related components

Check IC902 and

related components

Check Q501,

Q502 & R504

Replace and check

related circuitry

No

No

No

No

Is IC901 pin 27

output OK?

(H-USYNC)

Ye s

Is IC902 pin 17

output OK?

(H. Out)

Ye s

Is Q501 emitter

output OK?

Ye s

Is Q511 OK?

Replace and check

related circuitry

Replace and check

related circuitry

No

No

Ye s

Is T504 and FPRDs OK?

Ye s

Is Q507 OK?

Ye s

3

- 39 -

HIGH VOLTAGE

3

Replace Q503,

D509 and check

related components

Check Q510,

Q503 and related

components

Check IC501

and

related components

No

No

No

Is Q503 OK?

Ye s

Are Q510, Q503

and related

components OK?

Ye s

Is IC501 pins 18

&19 output

OK?

Resolder if necessary

No

Ye s

Is soldering or

mount around

RV501, C532 OK?

Ye s

Change FBT, verify

operation and
adjust monitor

Done

- 40 -

VERTICAL DEFLECTION

4

Check R412, R413

and power supply

Check IC902

& IC701

Verify IC401

and verify

No

No

No

Are IC401 pins 2

(+15V) and 4

(VSAW), IC701 pin 5

(VrefOut) & IC401 pin 3

Is IC401 OK?

(-15V) OK?

Ye s

Are

IC902 pin 8

waveforms

OK?

Ye s

Change DY

Adjust

monitor

Done

- 41 -

Ye s

HORIZONTAL SIZE

5

Check if IC501,

Q503 & Q510

OK

Check Q520 and

check related

components

Check IC902

Ye s

No

No

Are horizontal and
vertical size large?

No

Is Q520 OK?

Ye s

Is IC902 pin 9

(E/W) output OK?

Ye s

Repair H. Lin/ringing

correction circuit

Check IC501 and

related components

No

No

Is H Linearity OK?

Ye s

Is IC501 pins 18 & 19

output normal?

(Q503 Drive)

Ye s

Check T505 and

related components

Done

- 42 -

HORIZONTAL CENTER

6

Replace R526, R529

and check L510

Replace D530

and D531

No

No

Are

R526 and R529

OK?

Ye s

Are

D530 and D531

OK?

Ye s

Check L510

Done

- 43 -

KEY AND PIN

7

Check IC902

Check IC501 and

related components

No

No

IC902 pin 9 (E/W)

outputs normal?

Yes

Are IC501 and

related components

OK?

Yes

Check Q520 and

related components

Done

- 44 -

KEY AND PIN BALANCE

8

Check IC901

No

Check if

IC902 pin 18

output OK?

Yes

Check related circuit

components; fix

and adjust monitor

Done

- 45 -

ROTATION

9

Check for shorts,
check power supply
and check IC502

Replace IC502 and

adjust monitor

No

+15V and -15V

Normal?

Ye s

No

IC502 OK?

Ye s

Check rotation coil

and connections

Done

- 46 -

ABL FAILURE

10

Check IC901

ABL register

settings

Readjust

and verify

Check high

voltage circuits

Check IC901,

FBT and related

components

Replace CRT
and verify ABL

No

No

No

No

Is white balance
adjustment OK?

Ye s

Is anode voltage correct?

(26 KV)

Ye s

Is IC901 pin

input voltage OK?

(ABL)

Ye s Ye s

Is CRT OK?

Ye s

Check

if R546,

R545 and FBT

related circuit

OK?

No

Replace parts

& verify

Ye s

Replace D board

and verify

Done

- 47 -

DYNAMIC FOCUS

11

Check IC902

Replace and

adjust monitor

Replace and

adjust monitor

No

No

No

Is IC902 pin 12

output normal?

(V. Focus)

Ye s

Are Q504, Q505 and

related components

OK?

Ye s

Are T503 and related

components OK?

Ye s

Check connection

to FBT and

to Video board

Done

- 48 -

VIDEO

12

Check connector

CN309,

IC901 & +5V

Check
signal in

Check IC001

and
HV

Replace parts

& verify

No

No

No

No

Check if

2

I

C bus pins

1 & 2 of IC001

OK?

Check if

CN302 pins 2, 4

& 6 OK?

Ye s

Check if
IC001 pins 20,
24 and 27 OK?

Ye s

Check if IC002

pins 1, 3 & 5

OK?

Check IC004

and +B

Check CN301

and FBT

No

No

Ye s

Are cathode

DC levels correct?

Ye s

Is G2 voltage correct?

Ye s

Change CRT

Done

- 49 -

CONVERGENCE

13

"CONV_SW" REGISTER

Change

to "7" and

adjust monitor

Check IC701,
IC605 outputs

and +15V

power supply

Check IC702

and IC703

+15V & -15V

line power supply

No

No

No

Check "CONV_SW"

Register is "7"

Ye s

Check if

IC701 outputs

pins 8, 9, 6 and 7

are OK?

Ye s

Check

if IC702 outpins 1,

6, and IC703 output pins

2 and 8 are OK?

Ye s

Replace connector

and related

components

No

Ye s

Check

CN701 connector

if OK?

Ye s

Replace

DY and verify

if OK?

No

Change CRT

Done

- 50 -

Check F601, D601,

VA601, R600, TH600,

Q602 and see Power

Flow Chart (pg. 38)

R651, IC610 and C677

USB/AUDIO POWER SUPPLY

14

Check F601 and D601

No

Is C610/D635

Anode DC Rail

voltage correct?

Ye s

Check R651, IC610

and the front panel

power button

Remove CN605

and check USB

or Audio Circuit

Replace parts and

verify 6.5V output.

No

No

No

Does IC610

try to start?

Ye s

Is Load OK?

Ye s

Are C670,

C672, C673, C675, C676,

D633, D634, D635, D636, IC611,

PH601, R630, R631, R632,

R639 & R641

OK?

Ye s

Replace D Board

No

Operating?

Ye s

Verify 6.5V output with

0 Amp - 2 Amp load

Done

- 51 -

AUDIO

15

Check audio signal

source and cable

Check IC1702

and CN1701

Check IC1701

and related

components

No

No

No

Are proper

audio levels present

on J1702?

Ye s

Is VCC

supplied to

IC1701?

Ye s

Are proper audio

levels present on IC1701 pins

9, 12 and 16?

Ye s

Change Speaker

Done

- 52 -

- 53 -

9-978-878-02

Sony Corporation

Sony Technology Center

Technical Services

Service Promotion Department

- 54 -

English

2001BJ7415-1

Printed in USA

© 2001.3