RCA K51A Schematic

K51A

A-PDF MERGER DEMO

MAR/01

TV
Basic Service Data

General Information/Safety Precautions ......................................................................... 1-2

Disassembly ................................................................................................................... 2-1

Alignments ...................................................................................................................... 3-1

Troubleshooting Guides ................................................................................................. 4-1

Trouble Aids (Waveforms, Voltage, Timing Charts) ...................................................... 5-1

Replacement Partslist ..................................................................................................... 6-1

Exploded Views .............................................................................................................. 7-1

Block Diagrams ............................................................................................................... 8-1

Schematic Diagrams ........................................................................................................ 9-1

Circuit Boards ................................................................................................................. 10-1

K51A

Latin America After Sales

Indianapolis, IN 46290 U.S.A.

SERVICE DATA INDEX

Page

Number

CAUTION: Modification or repair of this unit by unauthorized persons is a direct violation of FCC Rules Part 68.216 and could

result in risk of electric shock. You are urged to contact a qualified factory authorized service facility for repairs.

SAFETY NOTICE

USE ISOLATION TRANSFORMER WHEN SERVICING

Components having special safety characteristics are identified by a ( ) on schematics and on the parts list in this Service Data and its bulletins.
Before servicing this instrument, it is important that the service technician read and follow the "Safety Precautions" in the Basic Service Data.

First Edition - First Printing
Copyright 2001 - Thomson Multimedia, Inc.
Printed in U.S.A. - Trademark(s)

®

Registered - Marca(s) Registrada(s)

K51A

Alignment and Adjustments

3-1

3. Alignment and Adjustments

3-1 Preadjustment

1. Since there are no VRs in the K51A chassis, all
adjustments after parts replacement must be
done in the Service Mode.

2. The Factory Mode adjustments are necessary
when either the EEPROM (IC902) or the CRT
is replaced.

3. Do not tamper with the Ò AdjustmentÓ screen
of the Factory Mode menu. This screen is
intended only for factory use.

4. WHEN EEPROM (IC902) IS REPLACED

(1) When IC902 is replaced, all adjustment data

revert to their initial values. It is necessary to
re-program this data.

(2) After IC902 is replaced, warm up the TV for

10 seconds.

Make the following adjustments AFTER
setting up purity and convergence:

White Balance
Sub-Brightness
Vertical Center
Vertical Size
Horizontal Size (No use in 21Ó and 25Ó

models)

3-2 Factory (“SERVICE”) Mode

1. The set must be in Factory (ÒServiceÓ) Mode.
Selection sequence:
STAND-BY ® MUTE ® 1 ®8 ® 2 ® POWER ON

2. The Ò FACTORY MODEÓ message will be displayed. The Factory Mode
has four components : Adjustment, MPX, PIP, Option Byte and Factory
Reset.

3. Access the Adjustment Mode by pressing the ÒVOLUMEÓ keys ( , )
The adjustment parameters are listed in the accompanying table.

Select them by pressing the CHANNEL keys (▲,▼).

4. After completing the Factory Mode adjustments, turn the power switch
OFF.

▼

▼

VSLN 30
VSN 32
VAN 32
HSN 45
EWAN 45
EWPN 33
EWCN 32
EWTN 38

*SERVICE*

¯

Press VOL

Press CH

Press VOL or

SBT 3

POWER OFF

Adjustment
MTS
PIP
Option
Reset

▼

AGC 15
VCO 62
SBT 7
SCT 11
SCR 8
STT 8
RG 32
GG 32
BG 32
SCO 20
PLA 5

¯

▼

¯

¯

▼

▼

VSLP 30
VSP 32
VAP 32
HSP 39
EWAP 46
EWPP 33
EWCP 32
EWPT 38

VSLN 30
VSN 32
VAN 32
HSN 45
EWAN 45
EWPN 33
EWCN 32
EWTN 38

AGC 15
VCO 62
SBT 7
SCT 11
SCR 8
STT 8
RG 32
GG 32
BG 32
SCO 20
PLA 5

VSLP 30
VSP 32
VAP 32
HSP 39
EWAP 46
EWPP 33
EWCP 32
EWPT 38

3-2-1 Adjustment

1. Selection sequence :
STAND-BY ® MUTE ® 1 ® 8 ® 2 ® POWER ON

2. Example : Sub-bright Adjustment

Alignment and Adjustments

3-2

SZM368ET2 (R4127)

Alignment and Adjustments

3-3

MEMORY SPECIFICATION

Table 3 - 1 Memory Specification

FUNCTION

A
D
J
U
S
T

M

E
N
T

OP

M

P
X

MODE

(OSD)
AGC

VCO
SBT
SCT
SCR

STT

RG
GG
BG

SCO

VSL

VS
VA
HS

EWA
EWP
EWC
EWT

PLA
SEP

TK2999ST

8

63

2
7
0

4
32
32
32
14
23
32
27
41
32
36
32
32

0

OFF

CD

50
13
46
32

290
300

40

290
300

1.4

2.4V

CR29805

8

63

2
7
0

4
32
32
32
14
23
32
27
41
32
36
32
32

0

OFF

8D
00
13
46
32

275
295

40

275
295

1.4

2.4V

UR29805

8

63

2
7
0

4
32
32
32
14
23
32
27
41
32
36
32
32

0

OFF

CD

50
13
46
32

290
300

40

290
283
300

2.4V

UR25805

8

63

2
7
0

4
32
32
32
14
23
32
27
41
32
36
32
32

0

OFF

CD

50
13
46
32

290
300

40

290
283
300

2.4V

RANGE

63

127

15
13
13
13
63
63
63
63
63
63
63
63
63
63
63
63
10
31
FF
FF
15
63
63

x
y

Y ± 5

x
y

Y ± 0.2

TK2599ST

8

63

2
7
0

4
32
32
32
14
23
32
27
41
32
36
32
32

0

OFF

C5
50
13
46
32

290
300

40

290
300

1.4

2.4V

No

1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20

BYTE 0
BYTE 1

ATT

SPECTRAL

WIDEBAND

HIGH - LIGHT

LOW - LIGHT

WHITE

BALANCE

ADJUSTMENT

MEASURING PULS ADJUSTMENT VOLTAGE

VIDEO MUTE

AUDIO MUTE

NO ATS

NO V - CHIP

NO VIDEO MUTE

NO AUDIO MUTE

ATS

V-CHIP

USA

PAL M/N

Alignment and Adjustments

3-4

3-2-2 Option Table

NOTE : The Option Adjustment must be done in the Service Mode.

3-2-2 (A) OPTION BYTE 00

Table 3-2 Option Byte 00

NAME

V-SYNC

AUTO ON

PIP

CATV

S-VIDEO

TONE

CRT

MPX

NOT USED

NOT USED
NO PIP FUNCTION
AIR/STD/HRC/IRC

NOT USED

NO TONE CONTROL

4 : 3 CRT

NOT USED

USED ( NO V-SYNC, POWER OFF)

USED

PIP FUNCTION

AIR/STD/HRC/AFN

USED

TONE CONTROL

12.8 : 9 CRT
USED

REMARK

ARMY : 1

3-2-2 (B) OPTION BYTE 01

BYTE : 00

D7
D6
D5
D4
D3
D2
D1
D0

FUNCTION

01

Table 3-3 Option Byte 01

NAME

AREA

LANGUAGE

NO VIDEO MUTE

NO AUDIO MUTE

ATS

V-CHIP

REMARK

SYSTEM/LANGUAGE

PAL

PAL

NT
NT

BYTE : 01

D7
D6

D5

D4

D3
D2
D1
D0

FUNCTION

01

00 : ENGLISH

01 : SPANISH (SEDA)

02 : PORTUGUESE

11 : NOT USED

Alignment and Adjustments

3-5

3-2-4 Factory Reset

When Ò Factory ResetÓ is selected, the User-Control data reverts to the initial values.
The User-Control data is available at MENU (picture, sound and the other functions).

Note : When Ò Factory ResetÓ is selected, the Factory Mode Data does not change.

Selection sequence :
Stand-By ® MUTE ® 1 ® 8 ® 2 ® POWER ON

* SERVICE *

Press VOL

Execute

Press CH

¯

▼

¯

▼

¯

Adjustment
MTS
PIP
Option
Reset

Adjustment
MTS
PIP
Option
Reset

3-3 Other Adjustments

3-3-1 General

1. Usually, a color TV needs only slight touch-up
adjustment upon installation. Check the basic
characteristics such as height, horizontal and
vertical sync and focus.

2. Observe the picture for good black and white
details. There should be no objectionable
color shading. If color shading is present,
perform the purity and convergence
adjustments described below.

3. Use the specified test equipment or its
equivalent.

4. Correct impedance matching is essential.

5. Avoid overload. Excessive signal from a
sweep generator might overload the front-end
of the TV. When inserting signal markers, do
not allow the marker generator to distort test
results.

6. Connect the TV only to an AC power source
with voltage and frequency as specified on the
backcover nameplate.

7. Do not attempt to connect or disconnect any
wires while the TV is turned on. Make sure
that the power cord is disconnected before
replacing any parts.

8. To protect against shock hazard, use an
isolation transformer.

SZM368ET2 (R4127)

Alignment and Adjustments

3-6

3-3-2 Automatic Degaussing

A degaussing coil is mounted around the
picture tube, so external degaussing after
moving the TV should be unnecessary.
However, the receiver must be properly
degaussed upon installation.

The degaussing coil operates for about 1
second after the power is switched ON. If the
set has been moved or turned in a different
direction, disconnect its AC power for at least
10 Minutes.

If the chassis or parts of the cabinet become
magnetized, poor color purity will result. If
this happens, use an external degaussing coil.
Slowly move the degaussing coil around the
faceplate of the picture tube and the sides and
front of the receiver. Slowly withdraw the coil
to a distance of about 6 feet before removing
power.

3-3-3 High Voltage Check

CAUTION : There is no high voltage
adjustment on this chassis. The B+ power
supply must be set to either +135V or +125V
(for 20Ó screen). Conditions : Full color bar
input and normal picture level.

1. Connect a digital voltmeter to the second
anode of the picture tube.

2. Turn on the TV. Set the Brightness and
Contrast controls to minimum (zero beam
current).

3. The high voltage must not exceed 29.5KV.

4. Adjust the Brightness and Contrast controls to
both extremes. Ensure that the high voltage
does not exceed 29.5KV under any conditions.

3-3-4 FOCUS Adjustment

1. Input a black and white signal.

2. Adjust the tuning control for the clearest
picture.

3. Adjust the FOCUS control for well defined
scanning lines in the center area of the screen.

3-3-5 B+Line Check

There are 3 power modes :

1. ÒAÓ : When AC power supply is connected ;
Ò Stand-ByÓ mode.

2. ÒBÓ : When Ò Set Power-ONÓ button is
pressed.

3. ÒCÓ : Driven by FBT.

Each voltage is marked on its lead-in wire.
( )

25”

29.5KV

29”

29.5KV

SIZE
MAX

H-VOLTAGE

Alignment and Adjustments

3-7

3-3-7 Color Purity Adjustment

1. Warm up the receiver. Operate it for 20
minutes, with the Brightness control set to
maximum.

2. Fully degauss the receiver. Use an external
degaussing coil.

3. Roughly adjust convergence by rotating the
Convergence Magnet.

4. Input a black and white signal.

5. Loosen the Deflection Yoke clamp screw, and
move the Deflection Yoke as close to the
purity magnet as possible.

6. Loosen the Purity Magnet clamp. Adjust the
purity magnet so that the vertical green raster
is precisely at the center of the screen. Then
tighten the clamp.

7. Slowly move the Deflection Yoke forward, and
adjust it for the best overall green screen.

8. Tighten the Deflection Yoke clamp screw.

Fig. 3-1 Tube Assembly

RUBBER WEDGES

30

30

LOCATION

DEFLECTION
YOKE

30

RUBBER WEDGE

ADHESIVE

RUBBER
WEDGES
KIT

RUBBER

WEDGES

PURITY AND
CONVERGENCE

MAGNET ASS'Y

CRT

DEFLECTION
YOKE

TAPE

CLOTH

GRASS

(1-3/16")

31 mm

Fig. 3-2 Purity and Convergence Magnets

2 POLE
PURITY

YOKE
CLAMP
SCREW

6 POLE

CONVERGENCE
4 POLE
CONVERGENCE

ADJUST THE ANGLE
(VERTICAL LINES)

FIXED

ROTATE TWO TABS
AT THE SAME TIME

(HORIZONTAL LINES)

Alignment and Adjustments

3-8

3-3-8 Center Convergence Adjustment

Note: Before attempting any convergence
adjustment, make sure that the receiver has
been powered ON for at least twenty minutes.

1. Input a crosshatch pattern from a color bar
generator.

2. Adjust the Brightness and Contrast controls
for a well defined pattern.

3. Adjust the two tabs of the 5-pole magnets.
Change the angle between the tabs, and
superimpose red and blue vertical lines in the
center area of the picture screen.

4. Next, turn both tabs at the same time. Keep
the angle between the tabs constant, and
superimpose the red and blue horizontal lines
at the center of the screen.

5. Adjust the two tabs of the 6-pole magnets.
Superimpose the red/blue lines on the green.
Adjusting the angle affects the horizontal
lines.

6. Repeat adjustments 3, 4 and 5. The dot
movement is complex because the 4-pole and
6-pole magnets interact.

Fig. 3-3 Center Convergence Adjustment

RED

BLUE

BLUE

RED

4-Pole Magnet Movement

GREEN

RED/BLUE

RED/BLUE

GREEN

6-Pole Magnet Movement

3-3-9 AGC Adjustment

1. Input a COLOR-BAR pattern. (CH2)

2. Set the RF input signal to 70 dBmV.

3. Use Generator for PM5518 & PM5418.

4. Set AGC (in the Factory Mode) so that the DC level of IC TDA8377
Pin 53 is 3.0±0.05V.

3-3-10 AFT (VCO Adjustment)

1. Input an AGC adjustment signal.

2. Select Factory Mode VCO and press the MUTE key one time.

3. GEOMATRIX adjustments

VS EWA
VA EWP
VSL EWC
HS EWT

Alignment and Adjustments

3-9

3-3-11 White Balance Adjustment

3-3-11 (A) SCREEN ADJUSTMENTS

1. Input a TOSHIBA pattern.

2. Check R506 ÒGÓ pin on the CRT PCB with an
oscilloscope.

3. Enter the Horizontal Line Mode.

4. Adjust the Screen Control on the FBT so that
the waveform of the 21st line is DC 2.0
(±0.5)V.

3-3-11 (B) HIGH-LIGHT ADJUSTMENT

1. NOTE : If a color analyzer is not available,
then approximate the following color
adjustments Òby eyeÓ.

2. Input a TOSHIBA pattern.

3. Set high-light to 290/300 (X,Y) with a color
analyzer.

4. Set low-light to 1.4F/L.

5. Adjust RG, BG and set GG to step 32.

3-3-11 (C) SUB-CONTRAST ADJUSTMENT

1. Set SCT so that the brightness level in high­light is 40 F/L (for a 29Ó SCREEN).

3-3-11 (D) SUB-BRIGHTNESS ADJUSTMENT

1. Input a TOSHIBA pattern.

2. Set SBT so that the brightness level in low­light is 1.4 F/L.

3-3-11 (E) SUB-COLOR ADJUSTMENT

Set ÒSCRÓ in the Service Mode to step 0.

3-3-11 (F) SUB-TINT ADJUSTMENT

Set ÒSTTÓ in the Service Mode to step 4.

3-3-11 (G) VERTICAL SIZE ADJUSTMENT

1. Input a lion head pattern.

2. Set VS to 32 in the Factory Mode.

3. Set VA so that the top margin is 4.0. Adjust SL
so that the bottom margin is 4.0. If the top
and bottom margins are different, adjust VA so
that their sum is 8.0.

3-3-11 (H) HORIZONTAL SHIFT ADJUSTMENT

1. Input a lion head pattern.

2. Adjust ÒHSÓ in the Service Mode so that the
left and right margins of the lion head pattern

are 6.3 ± 0.5.

SIZE

DC

29”

2.4

25”

2.4

HEIGHT

LIGHT

30”

33 ± 5

29”

37 ± 5

26”

45 ± 5

22”

45 ± 5

<TOSHIBA PATTERN>

High-Light

Low-Light

7. Block Diagrams

7-1 Main Block Diagram

Block Diagrams

8-1

JA701

EEPROM

TUNER

SIF

DETECTOR

CONTROL IC

MICOM

R/G/B AMP

DEFLECTION

HDRIZONTAL

DEFLECTION

VERTICAL

SAW

AC INPUT

TRANS

SAW

MULTI

REGULATOR

FBT

SPS

1-Chip

MTS

SOUND

AMP

JACK BLOCK

SPEAKER

TUO1

SF102

SF101

IC201

IC701

ICD01

IC201

IC501

Q401

IC301

T444

IC902

IC901

IC801

T801

IC853

5Volt
12Volt

130Volt

IC601

I2C

I

2

C

I2C

I

2

C

: video flow
: audio flow

CRT

Block Diagrams

8-2

7-2 VIDEO SIGNAL

SF101

MONO : M1963M

STEREO : M3951M

1

45

IC901

MICOM

IC501

TDA6108JF
(TDA6017Q)

JA701

JACK

BLOCK

VIDEO INPUT

TU01

TECC1070PG26A
TECC1070PG31A
TECC1970PG26A

IC201

TDA8377A/N3

49

48

13

17

1

6

19

20

21

VIF

Q201

R

G

B

2

3

22

23

24

OSD-R/G/B

SWITCHING /

13

17

CRT

Block Diagrams

8-3

7-3 AUDIO SIGNAL (MONO)

SF101

MONO:M1963M

STEREO : M3951M

1

45

JM08

JUMPER

49

48

6

2

6

15

1

VIF

Z601

+

3

L,C TRAP

(C222,C235,L217)

Q201

SPEAKER

-

8

SWITCHING /

IC201

TDA8377A/N3

JA701

JACK BLOCK

AUDIO INPUT

IC603

2

1

TU01

TECC1070PG26A
TECC1070PG31A

Block Diagrams

8-4

7-4 AUDIO SIGNAL (STEREO)

1

1

2

IC 60 3

TDA7266S

JA701

JACK

BLOCK

STEREO:6P

ICD01

CXA2104S

12

6

5

4

2

9

2

SIF

+

IC701

TDA7449

-

1

LA7510

4

5

45

6

15

18

SIF

R-OUT

2

7

L-OUT

R-OUT

78

R

L

L-OUT

L-OUT

400mVrms

L

R

R-OUT

400mVrms

14

15

+

-

SPEAKER-R

SPEAKER-L

SF102

MONO : M9260M

IC202

TU01

TECC1070PG26A
TECC1070PG31A
TECC1970PG26A

5-1 TK2599 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

5-2 TK2999ST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

5-3 CR29805 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6

5-4 UR25805 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8

5-5 UR29805 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10

Exploded Views & Parts List

7-1

5. Exploded Views & Parts List

Exploded Views & Parts List

7-2

5-5-1 TK2599ST

Exploded Views & Parts List

7-3

5-5-2 TK2999ST