atc113 training manual

8/12/2019 ATC113 Training Manual

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ATC113 TechnicalTraining Manual

VPORT



Page 1

Guide Plus+® is a registered trademark of Gemstar Development Corporation.

SAFETY INFORMATION

CAUTIONSafety information is contained in the appropriate Thomson multimedia Service Data. All product safety

requirements must be complied with prior to returning the instrument to the consumer. Servicers who

defeat safety features or fail to perform safety checks may be liable for any resulting damages and may

expose themselves and others to possible injury.

All integrated circuits, all surface mounted devices, and many other semi-

conductors are electrostatically sensitive and therefore require special

handling techniques.

First Edition - First Printing

Copyright 2002 Thomson multimedia Inc.

Trademark(s)® Registered Marca(s) Registrada(s)

Printed in U.S.A.

Prepared by

Thomson multimedia Inc.

Technical Training Department, INH905

PO Box 1976

Indianapolis, Indiana 46206 U.S.A.

This publication is intended to aid the technician in servicing the ATC113 television chassis. It will

explain the basic theory of operation. The manual covers power supply, Gem4 system control, and

YPrPb signal processing along with practical troubleshooting tips and suggestions. It is designed to

assist the technician in becoming familiar with chassis operation, increase confidence and improveoverall efficiency in servicing the product.

Note: This publication is intended to be used only as a training aid. It is not meant to replace service

data. TCE Electronic Service Information for this chassis contains specific information about parts,

safety and alignment procedures and must be consulted before performing any service. The informa-

tion in this manual is as accurate as possible at the time of publication. Circuit designs and drawings

are subject to change without notice.

FOREWORD



Page 2

Contents

FOREWORD ........................................................................................................ 1SAFETY INFORMATION CAUTION................................................................... 1

ATC113 INTRODUCTION ...................................................................................3ATC113 OVERVIEW............................................................................................4

GEMSTAR 4 AND SYSTEM CONTROL ............................................................6TROUBLESHOOTING THE GEM4 .................................................................... 7START-UP AND SHUTDOWN ............................................................................ 7

ATC113 Y PR PB PATH ...................................................................................... 8I/O MODULE TROUBLESHOOTING ................................................................8)

ATC113 POWER SUPPLY ..................................................................................9POWER SUPPLY OPERATION........................................................................10

KEY POINTS ABOUT THE ATC113 POWER SUPPLY .................................. 11POWER SUPPLY TROUBLESHOOTING TIPS ..............................................12



Page 3

ATC113 Introduction

Thomson’s latest TV chassis that will replace the CTC203 is the ATC113. This training

course will cover the ATC113 and its differences to the CTC203. First a general “Overview”

of key circuits of the ATC113 is covered followed by Gemstar 4 and troubleshooting the

GEM4. After the GEM4, this course will take the technician through the Y Pr Pb signal path

and I/O module troubleshooting followed by power supply and its operation. This course

ends with key points about the power supply and power supply troubleshooting tips. Upon

completion of this training course the service technician who is familiar with the CTC203

will be able to troubleshoot the ATC113 chassis.

The ATC113 is based on the CTC203 with minor changes. Aside from the obvious change

of the chassis numbering CTC to ATC, component numbering is the major change with

minor changes in the I/O and main chassis.

The changes that may or may not be covered in detail in this training course are:• All in one chip has changed to provide:

b. YPrPb inputs.

c. CRT Automatic Cut-Off Bias (ACB)d. Black level stretch.

e. 3.58 MHz output to synchronize a digital comb filter

f. Built-in horizontal oscillator without external resonator or alignment

g. Scan Velocity Modulation (SVM) output.• Audio amplifier is changed to increase audio power to 2 watts per channel.

• Audio BTSC stereo decoder IA01 is changed.

• Fly-back Transformer is changed to boost High Voltage by 1-2kV for improved

picture performance.

• ACRT driver IC is used to replace discrete components and improve video

performance.

In addition, the ATC113 has different I/O modules:I/O MODULE WITH V-PORT:

• This module will allow connection to the X-BOX via the 24-Way X-link cable, using

1H YPrPb and L/R signals from the X-BOX. Additional audio & video switch ICs will

be required to switch between X-BOX YPrPb and component YPrPb inputs.

I/O MODULE WITH PIP

• May or may not have V-Port connector.

I/O MODULE WITH COMB FILTER

• May or may not have PIP

BASIC I/O MODULE• No PIP or V-Port connector.

Audio and video switching IC (IY01) provides I2C bus communication and multi- A/V input

switching. All A/V switching is done on the I/O board.

The power supply and deflection circuits have stayed pretty much the same with only minor

changes.



Page 4

U26401

Gemstar 4

J 2 6 4 0 3

J 2 6 4 0 4

IV01Def. A/V

Processor

HorizontalOutputTL02

LL05IHVT

Vertical

OutputIF01

HYoke

V Yoke

AudioIA01

AudioOutput

IA03

EEPROMIR02

Stby I2C

EEPROMEnable

RGB

WBA

R/L Audio

Tuner

Video

IR out

FPA

Run I2C

OSD/FS

H/V Sync

IF

Run I2C

R/LAudTV

YPrPb Input

A/V Input

S-Video Input

Audio Input= CBA

= Chassis

PIP Tuner

IY03

IY01A/V

Sw

I/O & PIP CBA

6,7

34

38

14,15,16

4

ATC113 Overview

The ATC113 can be divided up into 3 main circuit areas: main chassis, Gemstar 4 module

and the I/O module. Major circuits on the main chassis are: Tuner, video processor,

horizontal output, vertical output, audio processing, audio output, and the EEPROM.

The main tuner processes NTSC RF signals and outputs IF to the video processor IV01

pins 6,7. TV Video is sent to the I/O for processing and is returned as Y Pr Pb from the IO

module. The Y Pr Pb signal is further processed by IV01 and output as RGB on pins 14,

15, and 16.

Audio comes out of IV01 as wide band audio on pin 4. The WBA signal is sent to IA01 for

processing into left and right audio signals. The audio processor decodes the stereo signal

and provides tone, volume, and balance adjustments to the audio signal. The audio

output is the final amp for speaker drive.

IV01 pin 34 is horizontal drive signal. This signal is further processed by the horizontal

output and used to drive the IHVT and the horizontal windings of the yoke.

Vertical output on pin 38 provides drive for the vertical output (IF01). IF01 is used to drivethe vertical windings of the yoke.

The EEPROM stores chassis alignment information and user settings. The alignments are

accessed using Chipper Check or front panel keys. Alignment and service menu access is

the same as the CTC203. For details on alignments, see the ATC113 ESI service data.



Page 5

There are three I2C busses in the ATC113 chassis, standby, run, and Gemstar. The

Standby bus is connected to the EEPROM (IR02). The Gemstar bus is internal to the

Gemstar module only and is used to communicate internal of the Gemstar module. The

run bus is connected to the remainder of the I2C devices: tuner, IV01, IA01, and I/O

module and provides communication throughout the chassis.

The Gemstar 4 module is the system control for the ATC113. It provides Gemstar guide

information processing and user input processing. The keyboard and IR commands are

processed by the Gemstar module and communicated to the chassis via I2C bus.

There are five I/O modules. Depending on inputs and features, these modules range from

a basic module with limited features to full feature module with PIP, V-port, and Y Pr Pb

inputs.

Most of the audio and video switching is done on the I/O by IY01. The comb/PIP processor

(IY03) provides PIP and Y/C switching / processing.



Page 7

Troubleshooting the Gem4

1. With AC power applied to the set.

2. Check BR104-14 for +5.2VE

3. Voltage incorrect or missing, troubleshoot STBY power supply4. Check BR103-10 and 12 (Clock & Data) for +5.0Vdc and 5Vp-p signal.

5. Signal present all the time troubleshoot main chassis and IR02.

6. Check BR104-4, 6, 8, and 10 for proper DC levels. Incorrect DC levels disconnect

BR202 and recheck.

7. Correct DC levels with BR202 disconnected troubleshoot keyboard.

8. Check for signal at BR104-12 and 13 when power button is pressed.

9. Clock and Data signal present when power is pressed troubleshoot the chassis.

10.Not present replace Gemstar module.

Start-up and Shutdown

3 Strikes and You’re Out ShutdownThe below error code table shows the different codes that can be thrown during the 3

strikes shutdown. The error codes can be viewed by accessing the service menu. Param-

eters 1, 2, and 3 are reserved for error codes. When viewing error codes for the first time it

is a good idea to reset all to zero and let the set go through the 3 strikes again. The new

error codes will indicate the first problem detected by the system control during start-up.

Error Code

(Dec) Device Condition

00 No error code thrown

03 U26401 Gemstar Micro 12V Run fault

08 IV01 XRP event detected

09 IV01 Power on reset

11 IY03 F2PIP Power on reset

12 IA01 Stereo Decoder Power on reset

16 U26401 Gemstar Micro Run I2C clock or data clamped at logic state 0

18 U26401 Gemstar Micro Stand-by I2C clock or data clamped at logic state 0

44 IY03 F2PIP No acknowledge from device

176 IA01 Stereo Decoder No acknowledge from device

180 3-Line Comb No acknowledge from device

144 IY01 A/V Switch No acknowledge from device

194 Tuner No acknowledge from device



Page 8

Buffer

26

4

5

GND

3

VCC

OUT

BIAS

1

IY07

Buffer

26

4

5

GND

3

VCC

OUT

BIAS

1

IY09

Buffer

26

4

5

GND

3

VCC

OUT

BIAS

1

IY08

IU01

I/O Board

Chassis

CRT Board

Y

Pr

PbR

G

B

XBoxConnector

Chassis

IV01

BY51

BV101

BY50

3233

16

XBox SW

47

43

44

14

15

16

ClockData

+5VE

Pb

Pr Pr

Pb Y

40 +9VE

IY01

Vcc

Yin

Yout

BY52

7 41

IY03 PIP

1

Y

ATC113 Y Pr Pb Path

The ATC113 is capable of two YPrPb inputs via conventional YPrPb cable and a special

cable connected to the V-Port (X-Box). Both inputs go three switch IC’s, IY09 for the Y

signal, IY07 for the Pr signal, and IY08 for the Pb signal. A voltage from the Gemstar

system control switches the three IC’s. BY51 pin 3 (XBOX SW) goes high approximately

3.1Vdc when the user selects V-Port input. When low, component input is selected. The Y

signal is further switched by IY01 (Audio / Video switch IC) and sent to the PIP processor or

comb filter. After PIP / Comb processing the Y signal along with Pr and Pb signals are sent

to connector BV101 and to the main chassis. All three signals are further processed by

IV01 and output as RGB to the CRT driver IU01.

I/O Module Troubleshooting

NOTE: Without the I/O module connected to the chassis the set will go through the 3-

strikes and you’re out shutdown.

The different I/O modules are board level troubleshooting. By checking the signals and

voltages to and from the I/O one can isolate down to board level. There are no set

procedures for this type of troubleshooting. Checking all signals and voltages on all

connectors is the only way to troubleshoot the I/O module. See service data for signal and

voltage requirements of each I/O.



Page 9

13

4 2

HOT COLD

HOT

COLD

HOT COLD

LP03

IP01

156VDCRaw B+

3

2

1

120VAC

FP01

5A

TP08

TP20

TP23

TP22

DP06

47V

DP22

DP31

DP26

DP40

CP08

DP80

DP63

DP75

CP23

IP50

DP30

16V

To DeGaussCircuit

DP01

RP20

RP31

RP21

RP23

RP27

RP28

RP30

RP25RP38

5

9

8

3

RP531

RegB+UB

TP552

TP553

DP57

RP52

RP559

CP550

RP56

RP558

RP54

+16VE

RP555 RP553RP53

CP24

ScanSupply

16

14

15

13

10

11

12

NC

Reg B+UB

-12VE

LP02

ShuntReg

CP80

CP64

CP76

4

3

2 1

+33VE

RP556

RP05

RP06

DP85

ATC113 Power Supply

The standby supply is a high power, ZVS (Z ero V oltage S witching) supply that minimizes

switching losses and radiated noise. ZVS refers to the ability of the supply causing thevoltage across the principal power output device, to reduce to near zero before the device

is switched on. Yet it has a slow enough time lag to allow the device to switch off

completely before any appreciable voltage is present across the device.

The MOSFET (TP20) begins conducting current when the gate voltage reaches the proper

turn on point. From that time, output current rises linearly due to the inductance of the

output transformer. However, once the gate voltage goes high, the drain voltage decreases



Page 10

almost to zero volts. This eliminates much of the heat dissipation normally required of an

output device.

By reducing the switching losses to almost zero, the efficiency of the power supply is

greatly increased and the limiting of the switching voltages causes a substantial reduction

of switching noise.

Power Supply Operation

When AC is applied, DP01 converts the AC to approximately 156Vdc that is filtered by

CP08.

This “Raw B+” has two paths. First is through the transformer LP03 to the drain of TP20.

Second is through a series of resistors (RP27, 23, and 21) to the gate of TP20. As you

might guess this path is the start voltage for TP20.

With both drain and gate voltage TP20 conducts pulling the drain voltage to near zero,

collapsing the energy stored in LP03 winding pins 3, 8. This collapse causes voltage to beinduced into the secondary windings of LP03.

The winding on LP03 pins 9 and 5 is the secondary winding used for TP20 gate drive and

bias for TP22 and TP23. The pulse from this winding is sent to the anode and cathode of

DP26 and DP40 respectively. The positive bias is for the oscillator control circuit of TP22

and TP23. The negative bias is for IP01 and regulation. The un-rectified pulse provides

initial gate drive of TP20 via RP38, CP23, RP23, and RP21.

Oscillation occurs as TP20 turns on and off. TP22 and TP23 function as a latch circuit to

turn off TP20. As TP20 conducts, current is pulled through RP20. At some point the voltage

across RP20 increases till TP22 turns on. TP22 turns on pulling the base of TP23 lower turning on TP23. With TP23 on, TP20 is turned off removing the voltage developed across

RP20 turning off TP22 and so on. The re-supply pulse and B+ through RP27 start the cycle

all over again.

Feedback is used to control the on time of TP20. The longer TP20 stays on, the more

current is developed in LP03. There are two feedback paths from the secondary side, the

+16V and the REG B+. Both voltages are required for proper regulation and run of the

power supply. IP50 shunt regulator controls the voltage across IP01 pins 1 and 2. As Reg

B+ goes up, IP50 becomes more resistive or open turning off IP01.

IP01 is used to couple the secondary to the primary. As the transistor in IP01 turns on

more, the less negative pin 4 becomes. This causes DP20’s emitter voltage to be more

positive. A more positive voltage on the emitter of TP22 means that the base voltage needs

to be more positive for it to turn on, there for TP20 stays on longer.



Page 11

Key points about the ATC113 ZVS power supply:• Stand-by operating frequency of 60 to 65KHz.

• RP20 over current protection.• DP30 over voltage protection.• TP552 and TP553 used for run mode current increase.•

If TP20 fails replace all active components on primary side.• Run operating frequency of 40 to 50KHz.

13

4 2

HOT COLD

HOT

COLD

HOT COLD

LP03

IP01

156VDCRaw B+

3

2

1

120VAC

FP01

5A

TP08

TP20

TP23

TP22

DP06

47V

DP22

DP31

DP26

DP40

CP08

DP80

DP63

DP75

CP23

IP50

DP30

16V

To DeGaussCircuit

DP01

RP20

RP31

RP21

RP23

RP27

RP28

RP30

RP25RP38

5

9

8

3

RP531

RegB+UB

TP552

TP553

DP57

RP52

RP559

CP550

RP56

RP558

RP54

+16VE

RP555 RP553RP53

CP24

ScanSupply

16

14

15

13

10

11

12

NC

Reg B+UB

-12VE

LP02

ShuntReg

CP80

CP64

CP76

4

3

2 1

+33VE

RP556

RP05

RP06

DP85



Page 12

Power Supply Troubleshooting Tips

NOTE: Voltage readings taken at 90VAC input using a Vari-AC.

Regulation Problem:

IP01 (Photo-Coupler) can be by-passed by shorting pins 1 and 2 of IP01, and connecting a

10K potentiometer across pins 3 and 4. With the potentiometer set to 10K the Reg B+ is

aprox. +140Vdc. At 7.5K the Reg B+ was aprox. +100Vdc.

IP50 can also be checked with the same setup as in IP01. As the Reg B+ goes up IP50

conducts. Monitoring pin 3 of IP50 and with Reg B+ at +100Vdc pin 3 is aporx. +12.5Vdc.

As Reg B+ goes up IP50 will conduct and pin 3 will drop to +1.8Vdc. By using the 10K

potentiometer one can vary the Reg B+ and check all functions of feedback control.

Start-up Problem:

Unsolder the Drain of TP20 and turn on the Vari-AC. The gate voltage of TP20 should

measure +11.5Vdc. Anything less check for loads in the star-up circuit. Anything more

check for an open in OSC circuit and DP06 circuit.

Check for shorts on the secondary of LP03. Excessive load on the power supply will cause

it to shutdown and pulse.

atc113 training manual

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