COLOUR TELEVISION TRAINING MANUAL - C&C …cncms.com.au/SANYO-SMs/Consumer-Electronics/CRT...COLOUR TELEVISION TRAINING MANUAL I FILE NO. c-?/Ps60-uo / Chassis Series ACI-A ACI-B ACI-C

COLOUR TELEVISIONTRAINING MANUAL

I FILE NO. c-?/Ps60-uo /

Chassis Series ACI-AACI-BACI-C

CIRCUIT DESCRIPTIONBLOCK DIAGRAM OF /~S

TROUBLE SHOOTING

I

REFERENCE NO. T1520009

i

Table of Contents

1.

2.

3.

4.

5.6.7.8.

1.

2.3.4.5.

1.

2.3.4.5.6.7.8.

Part 1 Chassis Description

Chassis Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3CPU. ......................................................................................&-18

2.1 A. DKeyldentification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...62.2 Option Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...7.92.3 Power On/ Standby . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lO2.4 Power Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..ll2.5 Band Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l22.6 Am . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l3.l42-7 TV/AV switch Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l52.8 Analogue Controls Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l5.l62-9 System Switch Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l7.l82-10 H/Vpulse input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..l9

IF/Video/Chroma/Deflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-213-1 lFstage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..2O3-2 Mdeo/Chroma stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..2l

3-3 Deflection Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..2l

System Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22-234-1 Sound Carrier Trap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...224.2 SIFFiltering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...23

Audio Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Vertical Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Horizontal Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Power Consumption Saving Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Part 2 Block Diagram of K%

LA7687 cl F/Video/Chroma/Deflection> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28LC89950 <1 H Delay line> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29LA7642 <SECAM Decoder> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29LA7837 cVertical Output> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30LA4285, LA4287 cAudio Output> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Part 3 Trouble Shooting Chart

Common start point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Dead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33-35No picture/No sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36-37Uo picture-sound OK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38No sound-picture OK .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39No colour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Aoncorrect colour phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .AlUo vertical deflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A2Uo on-screen display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A3

-2-

.

Training Manual AC 1 Chassis

Part 1 Chassis Description

1. Chassis SummaryThe following figure shows a basic block diagram of the AC1 chassis. This chassis is con-structed by the following ICS;

LC864508, IC801, for the CPU (system control circuit) for AC I -A chassisLC864512, IC801, for the CPU (system control circuit) for AC1 -B chassisLC864516, IC801, for the CPU (system control circuit) for AC1 -C chassisLA7687, IC201, for the IF, video, chroma de-modulation and deflection circuit

L

LC89950, IC271, for the 1H delay line circuitLA7642, IC280, for the SECAM decoder circuitLA7837, IC501, for the vertical deflection output circuitLA4287, ICOO1, for the audio output circuit, for AC1 -B chassisLA4285, ICOO1, for the audio output circuit, for AC1 -A and AC1 -C chassisST24C02AB, etc., IC802, for the control memory IC

...... ........52n-m

1- %..s:=~=~~ISASSEX

1 AUDIOIN

ESTERNM AUDIOIN ..

t—.

All LFOWR SUPWYCIRCUIT

—

-3-Training Manual AC 1Chassis

i

2 CPU (System Control)

The following figure shows a block diagram of the CPU peripheral circuit.

—.— .—-— -—. — -—-— -—-— -- —-— -—-— ,,,,,,

IiL

,,,,,

I

2C/3co

“Eo

TMlIIOalmZz$?t%C-JOIN+

i–.– -il.–.–.–.-.i

u-’N’

i—-—-—-—-—-—-—- l, f—-—-lr-—-— -

I

cum I:m

3.2cml

r%Gx—

IIiiiiiiii.J

,-–; di - nCe

&a)

r%.—-—.JI u

L._-—-—.—.—.—-—-_-—; L.—.—. —-— .—. J

-4-Training Manual ACl Chassis

The following table shows pin descriptions of the CPU for AC1-A, AC1-B and ACI-C,

L

L

Pin Description Pin Description—

1 Inhibit output & Option switch 27 Red signal output for OSD(AC1 -A) 28 Green signal output for OSDBass expander switch output & 29 Blue signal output for OSDOption switch (AC I -B, AC1 -C) 30 Blanking signal output for OSD

2 12Cbus SDA line 31 Not used3 12Cbus SCL line 32 Not used (AC1 -A, AC1 -B)4 AV/SECAM switch output AV1/AV2 switch output (AC1 -C)5 Option switch (Tuner type) 33 Not used (AC1 -A, AC1 -B)6 Option switch (No. of positions) Ignore input (AC1 -C)

(AC1 -A) 34 Not used (AC1 -A)Option switch (Blue back on/off) System switch output-VIF.M (AC1 -B,(AC1-B) AC1 -C)Option switch (No. of positions& AV 35 AFT defeat switch outputmodes) (AC1 -C) 36 Band switch output 1-VHF Low

7 Power& option switch (RC status) 37 Band switch output 2-VHF High8 Tuning voltage output 38 Band switch output 3-UHF9 GND (Digital) 39 Volume control output

10 Oscillator input for CPU 40 TV/AV switch output(TV:Low)11 Oscillator output for CPU 41 Power error detection input12 +5 power supply (Digital) 42 Sync identification input(No sync: Hi)13 AFT-S signal input 43 Colour killer input14 Key scan input (DC) 2 44 RC signal input15 Key scan input (DC) 1 45 SECAM killer input16 Option switch (Colour system) 46 IF identification input17 Reset pulse input 47 Not used (AC1 -A, AC1 -B)18 Oscillator input for OSD AV1 Start function input(ACl -C)19 Oscillator output for OSD 48 Option switch (No.of positions)20 Charge pump output (AC1 -A)21 +5 power supply (Analogue) Not used (AC1-B)22 GND (Analogue) Option switch (No of positions & AV23 Data-Analogue bus line modes) & AV2 Start function24 Address-Analogue bus line input(AC1-C)25 Vertical pulse input 49 SIF system output-DK & option SW.26 Horizontal pulse input 50 SIF system output-1 & option SW.

51 SIF system output-BG & option SW.52 SIF system output-M & option SW.

“-s-training Manual ACIChassis

2-1 A-D Key Identification Circuit

The key identification circuit used in this chassis uses a switched resistive ladder network ina A-D conversion circuit to generate and send a voltage to the CPU when a key is pressed.The CPU uses this voltage to determine which key was pressed. This resistive circuit elimi-nates the need for encoder/decoder devices, simplifying design and adding to the reliabilityof the TV.The table shows the voltages input to CPU pin 14 and 15, when a given key is pressed.

CPU

15

14 L

3-K1 5“ ~+—

~:j

27k K2 & 27k

10k &3 !W10k

5.6k & KJ 5.6k

3.9k ~ K~ 3.9k

2.2k ~ K~3 2.2k

2.7k K7 K~42.7k

0.27k 0.27k

lrwut voltaqe to pin 15

—7+

Intro It vnltarie to nin 14.----- --..-=- .- . ... . .

1KeK1K2K3K4K5K6K7

OFF

● Range of voltage0.5V-1.1 Vl.l V- 1.7V1.7V - 2.3V2.3V - 3.OV3.OU - 3.6V3.6V - 4.2V

more than 4.2VLess than 0.5V

FunctionPosition UpPostion UpPosition DownLevel UpLevel DownUndefinedUndefinedNo Key pressed

-tKeK8K9KI OK11K12K13K14

OFF

* Range of voltage0.5V-1.1 VI.lv- 1.7V1.7V - 2.3V2.3V - 3.OV3.OV - 3.6V3.6V - 4.2V

more than 4.2VLess than 0.5V

Function-rvlAvTVIAVSIF SystemColour SystemUndefinedPresetFunctionNo Key pressed

4

.

“ When the supply voltage is 5.OV.

-6-Training Manual AC 1 Chassis

L

.

L

2-2 Option switches

This chassis uses the option function switches to determine several different specificationsof the TV set.The CPU determines the specification of TV by detecting the voltage level on option switch-es pins, pins, 1, 5, 6, 7, 16,49 to 52.Following table shows the option functions and assigned pins of the CPU for each chassis.

Option functions &lcl-A AC1-B AC1-C

Inhibit pin 1 nla nla

Bass expander nla pin 1 pin 1Type of tuner pin 5 pin 5 pin 5

No.s of positions pins 6,48 nfa nlaNo.s of positions & AV modes nla nla pins 6, 48RC status pin 7 nla nlaBlue back in TV mode nla pin 6 nla

Colour system pin 16 pin 16 pin16

SIF system pins 49-52 pins 49-52 pins 49-52

* n/a = not available

Inhibit function (AC1-A chassis)

Buss

CPU

10

1‘9

expander function ( AC1-B and AC1-C

IN.SW Specificationoff w/o Inhibit functionon w/ Inhibit function

chassis)

CPU

RxEX.SW Specification

off w/o Bass expander function

1‘9

on w/ Bass expander function

Type of tuner

CPU

10TU.SW Specification

off Normal tuner

5‘Y

on CATV channel or hyper tuner

-7-Training Manual AC I Chassis

i

Numbers of programme positions (AC1-A chassis)

9CPU , 5“

k“10k

10kPOS2 Sw

6

48poa

Posl Sw‘ off

onoffon

POS2 Sw Specificationoff 60 programme positionsoff 30 programme positionson 100 programme positionson 100 programme positions

Numbers of programme positions and AV modes (AC1-C chassis)

CPU

6

48$%A5“

10k10k

POS2 Sw

poa

Remote control status (AC1-A chassis)

CPU

Rx

7‘9

Blue Back function in TV mode (AC1-B chassis)

CPU

Posl Swoff

on

off

on

on

off

off

Specification60 programme positions1 AV mode100 programme positions1 AV mode100 programme positions2 AV modes100 programme positions2 AV modes

RC SW. Specificationoff w/o remote control functionon w/ remote control function

BL.SW I Specificationoff w/ Blue back function in TV modeon w/o Blue back function in TV mode

-8-Training Manual AC1 Chassis

Colour system

CPU

J-1

5V

Rx

16

10k

SIF system

Pin16 Rx Specificationmore 4.53V 0.15K Not used3.9V-4.53V 1.8k Not used3.28V-3.9V 3.9k Not used2.66V-3.28V 6.8k China, Indonesia(ACl-B/C)2.03V-2.66V 12k Multi-system(AC l-B/C)1.41V-2.03V 18k 3 system0.78V-I .41V 33k VMT systemO.15V-O.78V 10Ok PAL systemless O.15V Open PAL system

● When the supply voltage is 5.OV.

I J711.sw BG.SW I.sw DK.SW Specification

off off off off Multi-systemoff off on off Pxoff off on on Indonesia 1on off off off 3 system (ACI -A)

on off on off East Europe

off on off off China 1off on on off China 2

on on off off China 3 (ACI-A)

off in on on Indonesia 2

on on on on No system (AC1 -A)


ii

2-3 Power/ stand-by circuit

O Power On/stand-byThe power on/stand-by signal is output from pin 7 of the CPU.When the stand-by mode is selected the voltage of pin 7 changes from Hi(5V) to Low(OV)to turn off Q682. Q682 turning off causes Q683 and Q684 to turn off. +24V supply for ver-tical and horizontal output circuit, +7.8V supply for lF/Video/Chroma circuit and +12V fortuner circuit are all cut off, resulting in the TV set going into the stand-by mode.When the TV is switched back into the power on mode, Q683 and Q684 are turned onand the relevant voltages are supplied back to each circuit.

, -.,-.,-.,-. . . . ..Q683● mmmmmmm. mmm mm.

. .

. .

.

. .

. .

. .

. .

. .

. .

. .

. .

: supply :

.:........ ...........................................

R68115k

7 AAA

7

5v --------

Power Ont

““sEd’by-””-”’”o’ ~

Q682

CPU

-1o-Traming Manual AC I Chassis

ii

2-4 Protection circuitL

This chassis employs two kinds of protection circuit, one controlled by software through theCPU and the other by hardware.

L

Protection circuit (software)

The protection circuit is provided to disable the operation of the TV set in case of a circuitmalfunction.When an abnormality occurs during TV reception it causes pin 41 of the CPU to go con-tinually Low (less than 0.8V) for about one second. The CPU detects that this hasoccurred and outputs the signal to cut off Q683 and Q684.

Protection circuit (hardware)

When a power failure is detected by diodes D643, D644 and D645, this protection circuitoperates causing the power oscillation to stop.If one of the above diodes is turned on, the voltage of Q631 -emitter decreases, and itturns on completely. Photo-coupler D615 is driven by this and generates a current whichdrives Q612 on. As a result, the operation of the power oscillation circuit is stopped.Under normal circumstances these parts, D615, Q631, D641, R635, R636, VR631 areoperating as the error detection and regulation circuit for +130V power supply.

D445 Heater

D201 ,5V

D492

I

180V, -.,-.,-.! -. 0-.., =a

i..■

✎

■

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

✎

Power

supplycircuit

● mmmmmmmmmmmmmd. .

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

. (

.

.

.

.

.

.

.

.

.

.

(2683t! Vert.&Horiz.

;

L1

Jlllll18!o.slllllll.!lL. ...............*@; & output i

- circuit‘j FBT j................

Q684 . “--’ --’--’=-’-J ,.. . . . . . :,,,,,...,,,,,,.,,..,,,,,..%

., -.,-.,-., -- i---. ............... I

+-@ ~- lF/Video/Chroma R

I.- . .- 1-------- ,.1.m-. a-. .-. m-. *-. .

:

i“m-, --}.-,.- ,.-,4

D655 ;

. [ 1/ I.. .. .. ... .. .+... mmmm. mmm. m

CPU

Protect 41

Power 7

R681

. . . . . . . . . . . .. . . . . . . . . . . . . . . ,,. ... as...,,,,.

R635

VR631 ....

Rf=$ :$\ : Poweroscillation

....■

h ADfj41 E)circuit :.

P................*. . . . . . . . . . . ..

130VRegulatorcircuit _ power

15kiAA

operation ~ failuer

Training Manual AC 1Chassis

-11-

i

2-5 Band switching circuit

The band switching control signals are output from pins 36, 37 and 38 of the CPU and fedto the base of Q1 03, Q104 and Q1 05, band switching transistors.The one of these transistors then supplies the drive voltage(+l 2V) to the tuner according tothe output signal from the CPU as shown below table.

Antenna

I._

Tuner

VL

VH

u

Cllo3●

12k

Q104● 12k

Q105● R898

12k

Band Switching Logic

output

Pin36 Pin 37 Pin 38 Q103 Q104 Q105 Selected Band

LH H on off off VHF-Low

HL H off on off VHF-High

HHL off off on UHF

36 VL

37 VH

38 UHF

CPU

-12-Tmining Manual AC1 Chassis

2-6 AFT

This chassis employs two kinds of the AFT circuit, it’s called the Digital AFT and the TraceAFT.The digital AFT operates as the hardware AFT in the tuner circuit. Every channel selection,the CPU reads out the tuning data from the memory and then changes tuning voltage outputfrom pin 8 to obtain the best tuned picture.The trace AFT is to prevent the drifting of receiving condition caused by the temperatureetc. The CPU monitors the AFT S-curve signal input to pin 13 and maintains the correcttuned picture by controlling the output tuning voltage.

. Digital An(1)

‘w (2)

(3)

(4)

The CPU outputs tuning voltage(Start value) which is subtracted with the step as table-1from the stored tuning voltage data in the memory and waits for 240ms.II* When the AFT voltage is less than 1.5V, go to step (4).

III* Other than the above, go to step (2).

Increase the tuning voltage along with table-2a until the AFT voltage reaches less than1.5V. Go to next step.Decrease the tuning voltage along with table-2b until the AFT voltage reaches more than2.OV. Go to next step.The CPU judges that the sync. signal is existing or not by detecting the voltage on pin46,If the CPU detects a low voltage on pin 46, go to step (2).

If the CPU detects a high(5V) voltage on pin 46, complete the digital AFT operation and

go to the Trace AFT stage.

Trace AmAfter completing the digital AFT operation, the CPU switches to the trace AFT mode.(1)

(2)

‘L (3)

If the AFT v;ltage ii more than 3.OV and the IF ident. signal is detected, the CPUincreases the tuning voltage along with table-3.If the AFT voltage is less than 2.OV and the IF ident. signal is detected, the CPUdecreases the tuning voltage along with table-3.In the preset mode and fine tuning mode, this function does not operate.

‘“L

Tablel Substructed steps Table-3 Tuning spesd of Trace AFT

~=

Table-2 Tuning apeed of digital AFT(a) High spead (steps/10msec.)

~

(b) Mid spead (steps/10msec.)

~


Tuning

CPU IC201

Tuner lF&VIDEO

Q184IF IDENT IN

TU ‘ 8 46 w 2 IF IDENTTUNING OUT R858

150

R177120k

R176 I7 AFT

39kJ? %::

AFTIN 13 4

F l\

RI 75

J? $:”82k

Input Signal

Pin 13 AFT S-Curveof IC801 Input

Pin 8of IC801

Pin 46of IC801

Tuning Voltage

3.5V

3.OV

-,:! 2.OV!,, A

IF Ident.Signal Input

‘ Tuned point

Input Voltage Level of Pin 13 Judgement

LL(OV-1.5V) Tuning Voltage Down

L (1.5V-2.OV) Tuning Voltage Down

M (2.O-3.OV) Tuned Centre

H (3. OV-3.5V) Tuning Voltage Up

HH(3.5V-5V) Tuning Voltage Up


2-7 TV/AV switching circuit

The TV/AV switching signal output from pin 40 of the CPU is supplied to pin 4 of ICOO1,audio output, and pin 1 of IC201 to select the internal or external source. The SECAMswitching signal output from pin 4 is sent to pin 1 of IC201. The output of each mode andsystem is shown in the table below.

40TVIAV

CPU

AV/SECA;

L To SECAM ICpin12 I Icool

I AUDIO OUTPUT

R8615.6k

-“45V

R8035.6k

R815 R804680 15k

d?

4 lNT./EXT. SW.

Q016

IC201lV/VIDEO

“1

1 AVISECAMRI 71 SIF INlk

TV I Av I

OUTPUT PAUNTSC SECAM PAUNTSC SECAM

pin 4 Hz L Hz H

Din 40 L L H H

● Hz= High impedance

2-8 Analogue control circuit

The colour saturation, brightness, contrast, tint, and sharpness for picture controls andselection of crystal control are controlled via the analogue bus lines connected from pins 23and 24 of the CPU to pins 18 and 19 of IC201, LA7687. The CPU outputs the data and

L address signals during a vertical retracing period, and the control address and data of crys-tal are represented in 8 bits and data of picture controls are represented in 7 bits.The timing charts and specifications of bus lines are described on next page.The sound volume control is output from pin 39 as 7 bits PWM (Pulse Width Modulation)signal. This signal is applied to the audio output IC as DC control voltage through the filter-ing circuit

IC201lF/VIDEO

CPU

23DATA

\ I

19 DataR219220

24ADDRESS

18 Address

39R218lk

IcoolAUDIO OUTPUT

VOLUME Filteringcircuit

* 5 VOL

-15-Traming Manual AC I Chassis

‘L

i

Output Value(1) Address voltaae (8 bits= 255 steDs)., “. ,,

Control Item Specification ofLA7687

1

Crystal O- O.17V

Brightness 0.77V - 1.OIV

Contrast 1.68V -1 .93V

Colour 2.59V - 2.83V

Sharpness 3.50V - 3.74VTint 4.40V - 5.00V

Reference output

voltage of CPU

O.oiv (02/255)

0.86V (44/255)

1.76V (90/255)

2.67V (136/255)

3.57V (182/255)

4.51V (230/255)

(2) Data voltagea) Crystal (8 bits= 255 steps)

Control Item Specification of Reference output

LA7687 voltage of CPU

PAL4.43 I O - 1.48V 0.04V (02/255)

PAL3.58 1.70V - 2.70V

NTSC3.58 2.90V - 3.90V

NTSC4.43 4.1 Ov - 5.00V

2.20V (112/255)

3.22V (164/255)

5.00V (255/255)

b) Picture control (7 bits=l 27 steps)

Control Item Reference output voltage of CPU

Minimum I Maxmum

BrightnessContrastColourSharpnessTint

0.43V (11/127)

2.48V (63/1 27)

Ov (0/1 27)

0.95V (24/1 27)

1 .22V (31/127)

2.91V (74/1 27)

4.96V (126/1 27)

4.96V (126/127)

3.43V (87/1 27)

3.7V (94/1 27)

Output timing chart1 Field

V-Sync

.-

Address

Data

5V//

//

—I

-16-Training Manual AC] Chassis

ii

2-9 System switch output

The outputs from pins 4,40and 340fthe CPUselect thecolour system and the outputsfrom pins 49 to 52 the SIF system. These outputs drive the colour and SIF system switchingcircuits. The operation of each switching circuit is shown in the table below.

Colour system switching output

Output pins

System Xtal/lD ~oltage(V) 4 40 34

PAL 0- 1.0 HzLL

TV SECAM 0- 1.0 LLL

NTSC4.43 4.0- 5.0 HzLL

NTSC 2.7- 3.6 HzLH

I I PAL ! 0- 1.0 ll-fz I-1*

IIAVSECAM 0- 1.0 HH*

NTSC4.43 4.0 -5.0 Hz H *

I I NTSC I 2.7- 3.6 I HzH*

“ It dependson receivingTV systemHZ= High impedance

SIF system switching output

1. Multi system

SIF system

rAuto

5.5 MHZ

6.OMHZ

6.5MHz

4.5MHZ

Output pins Display

52 51 50 49* HHH S1

LHLL S2

LLHL S3

LLLH S4

HLLL S5

“ The output level of pin 52 in the AUTO mode is determined bythe following condition

~AUTO BAN 50 L

TV . AUTO B/W HPAL 50 or 60 LSECAM 500r60 LNTSC4.43 50 or 60 LNTSC 50 or 60 H

AV It maintains the condition of TV mode.

2. PX system

6.5 MHz LLLH S3

4.5 MHZ HLLL S4

‘ Same condition with Multi-system

3. Indonesia a system

SIF system Output pins Display

52 51 50 49

Auto * HLL S15.5 MHZ LHLL S24.5MHZ HLLL S3

“ Same condition with Multi-system


i

L 3 system


52 51 50 49

Auto LHH H S1

5.5MHZ LHLL S2

6.OMHZ LLHL S3

6.5 MHz LLL H S4

5. a) East Europe systam(ACl -A/B)

S1F system Output pins Display

52 51 50 49

Auto LHL H SI

5.5MHZ LHL L S2

6.5 MHz LLL H S3

b) East Europe system(AC1-C)

S1F system I Output pins I Display

52 51 50 49

Auto LHL H SI

16.5MHz ILLL HI.52 I

5.5 MHZI

LHL L I S3I

6. No system


52 51 50 49

---- LLLL No Display

7. China a svstem

S1F system Output pins Display

52 51 50 49

Auto ● LHH S1

6.5MHz LLLH S2

6.OMHZ LLHL S3

4.5MHZ HLLL S4

8. China b system. SameconditionwithMultisystem

SIF system I Output pins Display

52 51 50 49

Auto ● LLH S1

6.5 MHz LLLH S2

4.5MHZ I HLLL I S3 I‘ Same condition with Multi system

9. China c system


52 51 50 49

Auto LLHH SI

6.5 MHz LLLH S2

6.OMHZ I I H L w?

10. Indonesia b system

Colour system Pin 34

Auto*

PAL L No Display

NTSC4.43 L

NTSC H

-18-Trainitig Manual AC) Chassis

2-10 Horiz./Vert. pulse input

‘.-

The vertical and horizontal pulses from the deflection circuits are input to pins 25 and 26 inorder to synchronise the On Screen Display.The vertical pulse is supplied from pin 20 of IC201 through the buffer and inverter circuit(Q845 and Q837).The horizontal pulse is supplied from pin 4 of the flyback transformer through the invertercircuit Q836.If one of these pulses is not supplied to the CPU, the on-screen display cannot be dis-played.

CPU

H-SYNC. 2f

V-SYNC. 2!

?

Ul_bv 5VR883/ Horiz.

3.3k

JL--l’lHnriz

\

I\

I

Vert.

u. u

Vert

I

T471FBT

IC201lF/Video/Chroma

20 V-DRIVE

V-Dfive pulse to V-OUTPUT IC


-19-

3. lF/Video/Chroma/Deflection

The following figure shows a block diagram of the lF/Video/Chroma/Deflection IC <LA7687>peripheral circuit.

3-1 IF stage

The IF signal output from the tuner is amplified by the pre-amplifier Q1 01, then sent to theSAW(Sutface Acoustic Wave) filter Xl 61. The output signal of the SAW filter Xl 61, is inputto pins 47 and 48. The IF signal thus input to the IC is then amplified by the IF amplifier, andis detected by the video detector with the VCO(Voltage Controlled Oscillation) circuit con-sisted of Xl 71 9,725 MHz oscillator and peripheral resistors, and it is output as a compositevideo signal at pin 8.This composite video signal passes through the 6.0MHZ(l)/6.5MHz( D/K) and 4.5 MHz(M)sound bandpass filtering circuit, and it is input into pin 1 of IC201. In the IC, this sound IFsignal passes through the SIF amplifier, FM detector and audio output circuit, and it is thenoutput from pin 51 as audio drive signal.

IC201X161 lF/VIDEO/CHROMA/DEF.

IC271TUNER Q101

SAWlH DELAYLINE

IF PREAMP.

X1719.725MH

J#o 1---

SIF CARRIER(4.516.016 .5MHZ

............. .................

~i$:MHJ+:.,.,,..,,,,.,,.,.,,,.,.,,,.,.,r

J:,,,,..,,.,,.,..,,.,,.,,.,,.,.~Tr%qE~!4.5/6.0/6.5fvll-tz!x,,.,..,..,. ,.,,..,,,,,.,,,.

+$7-VIDEO-OUT I

EXT. VIDEO-IN .AUDIO-OUT

-ANALOGUE BUS

\\ ..

=-+=+-L‘#

AUDIO

4748

5

1

8

10

14

51

1819

28

il

3f373E3~

33

:5

32

42

41

25

20

23

a 113

5ff

CRT

R-YIG-YIB-Y

\\\A

>

-Y

Q261

X242

~ H-DRIVE

m

~ V-DRIVE

in

-20-Training Manual ACI Chassis

3-2 Video/Chroma stage

“k.

L

The composite video signal output from pin 8 of IC201, passes through the QI 84 and thesound traps X181 (4.5 MHz), Xl 82(6. OMHZ) and Xl 83(6.5MHz) to reject the sound carriercomponents, is then supplied to pin 10. The external video signal from the AV terminal issupplied to pin 14.The video signal input to pin 10 or 14 is separated into the luminance(Y) and chrominance(C) signals in IC201. The chroma signal is divided into R-Y and B-Y colour difference sig-nals, which are demodulated and output from pin 38(B-Y) and 39( R-Y). These signal passthrough the 1H delay line circuit(lC271 ), and are re-input to pins 36(B-Y) and 37( R-Y).These R-Y/B-Y colour difference signals are supplied to the matrix circuit. The G-Y signal isgenerated by this circuit.The external RGB signals for the on-screen display or teletext display are input to pins29(B), 30(G) and 31(R). In the IC, the internal R-Y, G-Y, B-Y signals and the external R, G,B signals are mixed in the selection circuit driven by the blanking signal input to pin 28, andfinally output to pins 33, 34 and 35. The -Y(luminance) signal is output from pin 32.The colour saturation, contrast, brightness, tint and sharpness controls can be controlled bythe CPU in 7 bits digital data through the analogue bus lines on pins 18 and 19.

3-3 Deflection stage

The horizontal oscillator circuit provides a 500kHz ceramic oscillator X361 connected to pin23. The horizontal frequency is determined by dividing the frequency by a 1/32 downcounter. The horizontal drive pulse is sent from pin 25 and drives drive transistor Q431.The flyback pulse applied to pin 26 is performed the phase-shift by integrating circuit con-sisting of VR351 and C351, and used for the horizontal centring adjustment.The vertical sync. is generated by counting down the horizontal oscillation. The vertical drivepulse sent from pin 20 to pin 2 of IC501, vertical output IC<LA7837>.This IC has the automatic selection circuit for vertical sync. signal cycle from 50Hz or 60 Hz.It outputs the result to pin 21. If the IC selects 60 Hz, it outputs the High to the pin.

L


Q. S@Ml switches (AC1-A and Acl-c chassis only)

4-1 Sound Carrier Trap Circuit

When the 4.5 MHz system is selected, the CPU outputs a “High” signal from pin 34. Q181 isturned on and Q182 is turned off. As a result D182/Dl 84 are cut off and D181 is turned on.The composite video signal from pin 8 of IC201 is supplied to the base of QI 83 via the4.5 MHz trap circuit Xl 81 which removes the intercarrier sound content. From Q183 theCVBS video signal is fed to pin 10 of IC201. When other systems are selected the compos-ite video signal is fed through the 5.5 MHz/6 .OMHz trap Xl 82, or the 6.5 MHz trap Xl 83,which remove the respective intercarrier sound contents. The remaining video is fed to pin10 of IC201 via QI 83.This switching is shown in the table below.

10

IC201lF/Video/chrome

8

CPU

344.5 MHZ Sw

Video in .—. —. —. —. —- —- —. —- —-—-—-—-—-—-~~ .\

C21O1

r— L181

IR196220 i

+

/’ -Video out ~’—.—.

Q184

R184680

f1

R18310k $

1X1845.5 MHZ /

lk

2.2k

:R195 ‘ ~)

R188

D182

;C181115, R193,120

j

MJ!D{84

R185680

Xl 82

5!

5.516 .OMHZ

Xl 836.5 MHz

4R18227k

4 Q182

‘=I.XEE J

SIF System Pin 34 Q181 Q182 D181 D182

4.5 MHZ H On off On off

Other L off On off On

-


4-2 SIF Filtering Circuit

The video signal which also contains the SIF signal is output from pin 8 of IC201 and is sup-plied to the base of the buffer transistor Q1 37.The SIF signal output from Q137 is supplied to pin 1 of IC201 through the sound bandpassfiltering circuit. The relevant bandpass filters Xl 34 (4.5 MHz), Xl 33 (5.5 MHz), Xl 32(6.OMHZ), X131 (6.5MHz) are selected according to the output signals from pins 49 to 52 ofthe CPU. The SIF signal is then fed via the relevant bufferQ134 (4.5MHz), Q133 (5.5MHz),Q132 (6.OMHZ), Q131 (6.5MHz) to the SIF input pin 1 of IC201 for de-modulation.

IC201lfNideo/chroma 8

SIF Input 1

-

52

CPU

5C

51

49

Video + Sound Carrier Output h

Sound Carrier4

Q184

SIF Filterina Circuit

SIF Svstem

Auto

5.5 MHZ

6.OMHZ

6.5 MHz

4.5MHZ

1 Q136

Q134 X1344.5 MHZ F

II

() 1111

T T

J

J

Q133 p J

II( + q-r -/+X133 Q135

5 5MHZ

J

Q132

II

4+

q?’ ‘

J

X1326.OMHZ

Q131

“kT”

II

X1316.5 MHz

J

TPin52 Pin51

* H

L H

L L

LL

H L

‘in 50

H

L

H

L

L ITPin49 Q134 Q133

H * On

L Off On

L off offH off off

L On Off TQ132 Q131

On On

off off

On Off

Off On

off off

-f

Training Manuel AC] Chassis

‘ It depends on receiving system,

-23-

5. Audio Output

The internal audio signal from pin 51 of IC201 is supplied to pin 1 of ICOO1, audio output -LA4285, for AC1 -A and AC1 -C, LA4287 for AC1 -B. The external audio signal is supplied to pin3 of ICOO1. Either of audio signals is selected by the Internal/External switching signal inputto pin 4.The selected audio signal passes through the pre-amplifier circuit and the drive circuit into theaudio amplifier. The sound volume control is supplied from pin 39 of the CPU to pin 5 of ICOO1through the digital-analogue converter circuit. The audio amplifier is the SEPP(Single EndedPush Pull) type and the output from pin 9 drives the speaker directly.

IC201lF/VIDEO/CHROMA

b’

Q184 ,...........................

8 : SOUND !; FILTERING :E CIRCUIT :

. ........... .............

SIF Carrier1

3(nFz

w2y

1- 3~ g

I I HEADPHONE

\ I \ ( v

51INT.AUDIO

> 1+4 5

9 SPEAKER

> 3-0

J IcoolAUDIO OUTPUT

EXT.AUDIO-IN

-


i

6. Vertical Output

This chassis employs an LA7837 for the vertical output circuit. It incorporates a built-in rampgenerator circuit, constant vertical height function for 50/60Hz operation and pump-up cir-cuit.The vertical trigger pulse is driven by the negative polarity vertical sync pulse from theIC201. The ramp generator circuit generates the vertical deflection sawtooth waveform. Thesawtooth waveform is generated by charging and discharging the current in C513 connect-ed to pin 6. This ramp signal drives the vertical drive circuit. In the first half of scanning peri-od, a deflecting current is sent from pin 12 and passes through the following path;VCC(24V) + D512 + pin 13 + pin 12 + DY + C515 + R518.

An electric charge is then stored in C515. In the last half of scanning period, the currentpath is; C515 -+ DY + pin 12 + pin ll(GND) + R518.In this way, an increasing sawtooth waveform current flows directly to the DY to performelectron beam deflection. During the first half of the blanking period, the vertical ramp signalsuddenly turns off. Since there is no longer any current flowing into the DY, the magneticfield collapses causing an induced current to flow as flows;DY+ pin 12+ pin 11 +R518-C515+DY.

Once the magnetic field in DY has dissipated, the current path becomes;Vcc+pin 8+pin9+C517+ pin 13~pin 12+ DY+C515+R518

and when the prescribed current value is reached. the vertical drive pulse turns on. Thiscompletes one cycle.VR51 O is for controlling the amount of feedback applied to pin 4 for the vertical size adjust-ment.

IC501VERT. 0UTPUT<LA7837>

IC201lF/VIDEO/DEF.

1234567891011 1213

2(

21

lrl

+~’3

D.Y

V.COIL

VR51OV-SIZE

t

I jR518

.=------------ Curmnl W of firs! half uf scanning *rid

i ~5

—-— Cumntff0w0fh5 thalf0f5cann*@d

Training Manual AC lChassis

-25-

7. Horizontal Output

The horizontal oscillator signal is output from pin 25 of IC201 and used for switching the -drive transistor Q431. This switching signal is current amplified by the drive transformerT431 and drives the output transistor Q432. When Q432 turns ON, an increasing currentflows directly to the DY throughC441/C442 + L441 /R441 + DY + Q432-C + Q432-Eand the deflection occurs during the last half of the scanning period. When Q432 turns OFF,the magnetic field stored in the DY up to that point causes a resonant current to flow intothe capacitors C435 and charges them. The current stored in C435 then flows back to theDY causing an opposite magnetic field to be stored in the DY. This field then collapsesincreasing a current which switches the dumper diode in Q432 ON. The resonance state iscompleted, and an increasing current then flows again directly to the DY through thedumper diode.By this means, the deflection in the first half of the scanning period is performed. WhenQ432 turns ON at the end of the first half of the scanning period, the deflection during thelast half is begun, thus completing one cycle.

IC201lF/VIDEO/DEF.

I Mrl!iI L’.--?c-?c!:L‘p“,=................................'........L44.~...............".‘:25~ R441

JL=12oovp-p

DYQ432r-—-—-—-—-— -—-—-—-—-—.,:””

I T431................... .......... ... ..... .. .. .. ...................... :

~.:. ] : ::—,

I H-DRIvE > —I [’ ........l............<..~ I 1

H COIL

J‘-\ h b1 C441 C442

Q431 R435 C437 ------------Current flow of first half of scanning period

m—-— Current flow of Iaat half of scanning period

.

-26-Training Manuaf AC1 Chassis

8. Power Consumption Saving Circuit

This chassis employs the interval oscillation circuit on the power circuit for saving the con-sumption of power supply circuit during the stand-by modeThe interval oscillation circuit consists of Q685, Q686, D685 and peripheral circuit. Q685and Q686 drives the photo-coupler D615 and oscillation of power circuit according to volt-age level on point (A) in the figure. During power-on mode, the voltage on point (A) isalmost OV and Q685 and Q686 maintain turning-off.When the set switches into stand-by mode, the voltage on point (A) increases about 15V.The voltage which is divided with R688 and R687 is applied to Q685-base and drives Q685and Q686 turning-on. When Q686 turns on, the photo-diode/transistor in D61 5 is completelyturned on, then Q612 is turned on and Q613 is turned off. By this means, the oscillation of

. power circuit stops and the voltage of secondary power supply falls down. Also the voltageof point (A) falls down from 15V gradually.When the voltage on Q685-base is less than voltage of Q685-emitter, Q685 is turned offand then Q686 is off, then D615 and Q612 are turned off. Finally Q613 starts the oscillationand the voltages are supplied to the secondary circuit. By this means, the voltage on point

\ (A) rises up and drives Q685 on again. By repeating the above operation, the power con-sumption in the stand-by mode can be saved.

I h

PD615

R615

L

,

,

-1T611

Q613Q612

Oscillation stage Output stage

Q684

R68410k

To stand-bydrive circuit

hR68922k

Q685

R68810k R687

Q686560k

D6856.2V

Zb

Power-on1

Stand-byI 15V

Voltage deviation

of point@

"""m""""""""""""""""""""."""."'....""."."""""...."l"""""""""""""""""""""""""""""""""""-

.........-

-—-—-—-

“>...... -_

1 Ovla n

Operating period of power circuit


ii

Part 2 Block Diagram of ICS

1. LA7687 <lF/Video/Chroma/Deflection>

HhAV-SWL5ECAM ~

LA7687

i

4.5MHZ

l!!5.5MHZ

1! -.

ID OUT %M-r

An OUT ~

SOUN[TRAP

a-w-l<

3++<

3-ID “9.5MHZ

T

s

.

VIDEOOUT a

~,%

‘ I +%-l bWFIN

Al, s-! l-l-lA

> H tJ3,58MHz“.. . . .5

ACL.+--i i-J

S-SW ()c

3-II-J

S-CHROMA~c

I1

EXT-VIDEOOz,,

Vcc 5V o--

ABL O

KILLER ~=

BUS 1 ()G

HI-J

BUS20z

4---IIJg

V-OUTO

if —

GND—

II11~1 “1 I 1112-1

I I 1 1 1

N

50160HzO

. .

L

,.—

du I

-28-Tmining Manual AC1 Chassis

i

2. Vertical Output <LA7837>

m

r“ ILTHERMAL

VERT.PROTECTION

TRIGGER RAMPGENERATORINPUT

1i

, ~OUTPUT

ONESHOT V-SIZE

MULTI CONTROLSWITCH

4)

/ccl IA

VCC2 1 I \ r

2 3 4 5 ( 7 8 9 10 11 12m%+ g 2

m=3+C1. m~ c 3>~ 0 I

u II ()u @k s J

(

c1VCC2

3.1 H Delay Line <LC89950>

I Vss

B-Y

IN

Vdd

R-YIN

4MHZOUT

~

COMP

4BGP LC89950 14

5CLAMP CCD

I +.1OUTPUT 3

+254.5bii S&G, AMP

A

I I

A

01 02

~%n 4 ‘>LEVEL

AUTO-BIASINCREASER

CLAMP CCD OUTPUT 1254.5bit S&G, AMP

tBGP

8

CLOCK DRIVER,

L 41A

4 BGP. .—

c=BGP 13

DETECTOR ~

12

OUT

I

‘ OUT

PIN

~

Training Manual AC 1Chsssis

VCO IN

-29-

/PC OUT

4. SECAM Decoder <LA7642>

Vcc VIDEO IN KIL OUT AV/SECAM 4.43 MHz IN SC IN 4.43MHz IN

o

~

o 0 Q~

II z ~ ~~o1. 1- — ~0 1 m

2 z J (/2 * 10 > c1

< G S2’‘ +~

> (n u)

16 15 14 13 12

+

11 9

T T +

ACC SW3 + SYSTEM[,1

SN2

‘“=

PULSE

DET.1

I I I I I

I t +BELIJEQU BELIJEQU Swl LIMADJ FILTER 4

LA7642 i

KILLERPLLDET. Vco CLAMP

1

m--i

IDKIL

IDI

FIL

1 2 3[ 4 ‘5 6! 7], ,. 1 . . I LI . I

5. Audio Output <LA4285, LA4287>

LA4285

4---

I

-

p!cc 4 I GND ] NF I I GND

7 6 5 4 3 2 1

Vcc_ INT. AUDIO IN

VOLUME

k

~ EXT.AUDIOIN

Di

CONTROLSPL4KER

lNT./EXT.SW

7)7


MEMO:


Part 3 Trouble Shooting Chart

Common startpoint Chassis Series: AC1

I IDead

~ ‘age’’-”1 I 1

No picture/No sound * Page 36-37

No picture-sound OK * Page 38

I I I

No sound-picture OK~ ‘age”

I I I

No colour > Page 40

Incorrect colour phase w Page 41

No vertical deflection * Page 42

No on-screen display * Page 43


Trouble Shooting Chart Startpoint symptom: Dead

NoIs the fuse OK ? *

IYes

Check voltage on both ends ofC607 ?

F

L

Check power primary circuit,C601 , C602, VA601 , PS601 ,C607, Q611 , Q612, Q613, C615,R626, D615,Secondary circuit, Q631, C641,R635, VR631 , D641 , Q432,C435, C436, R636

-1

L

I+300V

●

Check voltage on pin 1 of IC651 ?+

+15V

AC cord, SW601, F601, L601,R602

Q611 , Q612, Q613, C617, R620,R621 , R622, D625, C616, R624,D634, C644, C643, C645, D641 ,ICOO1, CO07, T611 ,L603, L606,Q686, Q685, D685

tNo 1(3651, C651 , IC801 , IC802,

Is the power LED lighting ? > C815, C816, C801 , C828, C81O,I I,

YesI C809 I

+

Check voltage(+24V) on Q683- Ov* D633, R643

emitter1

+24V

v

Check voltage(+l 30V) on both Ov

ends of C641- C641 , D631

+130V or more

tF---- ---------- ------ -------------- 1

i

~ Go to next page1I IL ------- ------- -------------- ------- J

L


-33-

i


1Disconnect error detector diodes, D646,D654, D655, D455, D492, D201 and transis-tor Q527, Q449

I

r --------------------------- ------ -- 1:’ To avoid the damage to the other circuits, :: please turn TV set on for 2-3 seconds for :~ checking i

L --------------------------- ------ -- J

Check follows

*

Does a horizontal line appear on Yes Check vertical deflection circuit,

the screen ? * IC501 , Q527, R518, C515, C524,C517, C520, D507, DY

1

No

t

OvCheck voltage on pin 41 of IC801 R855, C855, IC801 and check

error detection lines

Check voltage(+24V) on Q683-col- Ov Q683, R683, Q682, R681 ,Iector * IC501 , C521

+24V

vCheck voltage(+l 5V) on Q684-col- Ov

Iector* Q684, R685, D683.

+15V

,

Check voltage(+l 2V) on Q652- +Ov Short circuit on 12V line, check

emitter ~ Q652, R652, R653, D652, C652,C654, C510, C106, C119, IC501,

+12V tuner

+ Short c wit on 7.8V line, check

Check voltage(+7.8V) on Q653- ‘es Q653, W356, D653, C653, C655,

emitter w R654, R655, IC201 , c130, C139,

L_____ -_---- _--. --------------------i

-34-~rai .,ing Manual AC I Chassis

i


/

vEl

mHoriz. IV

Check waveform on pin 25 of No

IC201w

Check waveform on Q431 -collector D

IC201 , X361 , R365

1

No Horiz. output circuit, Q432, C435,Is the CRT heater coil lighting ? ~ R435, R442, L441 , T471 , T431 ,

Check voltage on terminal KQS-1+

I

180V

Check voltage on both ends ofC445 +

1+5 to +1OV

Q449, R449, R446, R447

DY, R451

C429, D491 , C491

C445, D442, R448

Training Manual ACIChassis

-35-

ii

Trouble Shooting Chart Startpoint symptom: No picture/No sound

~

.----------- ------------ ------ ---Nc) ~

q

Is CRT heater lighting ? >: Go to chapter “Dead” on page 33 III I

I L ------- ------- ------- ------- ----- J

Yes

v ❑AHorlz. 1.5V

Is video signal observed on Q1 83- Yes~ IC201 , Q183, SW191 , R192,

base ? R190, C21O

No

v 1.5ElIs video signal observed on Q1 84- Yes Q1 83, R196, sound trap circuit,

emitter ? w X181, X182, X183, D181-D184,R188 etc.

Is video signal observed on pin 8 ofI Iiclrizl.,v I yes -

IC201 ?* Q184, R197

1r I L I

No

t

Check voltage(+33V) on both ends Ov- R816, D801 , C829

of D801

+33V

Is tuning voltage changing on termi- No

nal TU on the tuner when tuning ?>

Yes OV to +33V

r ----b-- -------------- --------------1

I Go to next page ~1I I

Check tuning circuit, IC801,Q813, R811 , R81O, C805, C806,R813, R814, C803, C802, R809,R106, C102, L802, R813

IL ------- ------- ------- ------- ------- i

-36-Trsining Manual AC1 Chassis

i

Trouble Shooting Chart Startpoint symptom: No picture/No sound

L

t

Is supply voltage (+12V) observed No

on terminal LB, HB, U on the tuner *

correctly ?.

IYes

VL: Q1 03, R896, Cl 05VH: QI04, R897, C103U: QI05, R898, C101IC801

t

Check AGC voltage on terminal O or +12V

AGC on the tunerw C104, R164, R165, C108, C168

+3V to +6V

L YCheck aerial cable, tuner and IFperipheral circuit, IC201, Q1 01,X161, X171, C162, C197

OR

Memorv circuitIC802, R801 , R802, R807, R808,R867, R868AFT circuitR177, C177, R176, R175Video detection circuitX171, R174, C176, R173, R170,C175, C172, C178Ident. circuit to CPUC858, R858, R859, IC201TV/AV switch circuitR171 , R815, IC801

L

Training Manual AC lChassis

-37-

i

Trouble Shooting Chart Startpoint symptom: No picture-sound OK

F1--’--1Horiz. 8V

Is -Y signal observed on pin 32 ofIC201 ?

~

Is -Y signal observed on Q261 -emitter ?

~

L731, C731, screen circuit, T471

No

El

‘WIHoliz. 8V

No

IC201, L241, C211, R211, R222,R224, C222

Q261 , R232, R263, D232, Q252,Q251 , D251


Trouble Shooting Chart Startpoint symptom: No sound-picture OK

+5VCheck voltage on pin 42 of IC801 - Q806, IC201 , R871

n

I Ov

tOv

Check voltage on pin 46 of IC801 b

+5V

w

R859, R858, C858, IC201 , IC801

Check voltage on pin 5 of ICOO1

H,c801’c824L848

‘v C822 C823 R851, R852, R885,when the maximum volume setting

+6V

IEl

m0.5V

Check waveform on pin 9 of ICOO1‘es Speakers, headphone socket,

* CO05, CO06I I I

1

I No

El

m0.5V

Check waveform on pin 51 of ‘es ICOO1, Q016, COO1, C016, C172,IC201 w R166, CO04, CO03, R016

No

Check SIF filterincl circuitNo sound on all of systems --> Check C171, R152, Q137, L132, R151, C147 peripheral

circuitNo sound on 6.5 MHz system--> Check Q1 35, Q1 31, R832, Xl 31, C131 peripheral circuitNo sound on 6.OMHZ system --> Check QI 35, Q1 32, R833, Xl 32, Cl 32 peripheral circuitNo sound on 4.5 MHz system --> Check Q1 36, Q134, R835, X134, C134 peripheral circuit

“39-Training Manual ACIChassis

Trouble Shooting Chart Startpoint symptom: No colour

-

YesNo colour on NTSC system *

No colour on PAL system&

X241 , IC201

No colour on SECAM system‘es SECAM decoder peripheral cir-

- cuit, IC281, C281, C283, C884,

I C285, C286, C287, C288, Q281No colour on all of systems 1

v

T471 , R351 , R352, R353, D352,R354

.

-?


i

.

L’

Trouble Shooting Chart Startpoint symptom: Incorrect colour phase

Incorrect colour phase

Excessive red colour ●

Loss or poor red colour

Q711,C712,

R71 2A,R711

VR711 VR712,

Q711, VR712, VR711 , R235,w R714

Excessive green colourQ721 , R721 , R722, C722,

- VR721

1

Loss or poor green colour * Q721 , VR721 , R724, R233

L Excessive blue colourQ701 , R701 A, R702A, VR701 ,

w VR702, C702

&

.

1

Loss or poor blue colourQ701 , VR701 , VR702, R704,

w R234

Incorrect colour phase DIC271 peripheral circuitC271 , C273, C274, C237, C236,C278, C289

L

-41-Training Manual ACIChassis

i

Trouble Shooting Cnart Startpoint symptom: No vertical deflection

~

OvCheck voltage on pin 13 of IC501 w L511, D512

Vert. IV

Check waveform on pin 6 of IC501A

IC501 , IC201 , C512, C513, D513,R512, C511, R511, SW191

Yes

R513, C515, C518, R518, C524,DY

Compressed or expanded vertical Q526, VR51 O, R525, R514,

screen size > R515, R522, C514, R516, C513,R526

.


i

Trouble Shooting Charl Startpoint symptom: No on-screen display

IINo on-screen display

11.ruCheck waveform on pin 26 ofIC801

‘ “~1Yes

1 •IVeft. 5V

Check waveform on pin 25 of ‘0 w Q837, R837, R838, C819, Q839,IC801 R846, Q845

I

Yes

IC801 , C812, C813, L804, R228

-43-TrainingManualACIChessis

TRAINING MANUAL AC1

Al 4800/Jun.96/500/Sl

s!ifgwwoSANYO Electric Co., Ltd.

Training Manual ACI Chassis

COLOUR TELEVISION TRAINING MANUAL - C&C …cncms.com.au/SANYO-SMs/Consumer-Electronics/CRT...COLOUR TELEVISION TRAINING MANUAL I FILE NO. c-?/Ps60-uo / Chassis Series ACI-A ACI-B ACI-C

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