AKIRA CT-14F9 Service Manual

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CHASSIS: 8803

MODEL:

CT-14FES1

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Model No: CT-14FES1
Version 1.0

3

CONTENT

GENERAL DESCRIPTION..................................................................................................................... 4

CONNECTOR VIEW .............................................................................................................................. 5

SAFETY INSTRUCTIONS ..................................................................................................................... 5

CIRCUIT ADJUSTMENTS..................................................................................................................... 6

FAULT FINDING TREES, DIAGRAMS AND OVERVIEWS............................................................ 12

VARIOUS PARAMETERS OF INTEGRATED CIRCUIT..................................................................25

THE BUS DATA FOR TMPA8803....................................................................................................... 25

ELECTRICAL PARTS LIST................................................................................................................. 28

CIRCUIT DIAGRAM............................................................................................................................ 37

Model No: CT-14FES1
Version 1.0

4

GENERAL DESCRIPTION

AKTP01 /02 chassis series are applied A14T02/A14T02a respectively which uses mainly TOSHIBA’
advanced UOC-ultimate chip TMPA8803/8821 and I
controller and small signal processor, the TMPA8803/8821 series feature high-integration, high­performance-to-price ratio and high-reliability and advanced functions with fewer external
components, which provide much convenience for manufacturing and technical service.

Figure 1: shows the block diagram of AKTP01 (A14T02).
Table 1: provides A14T02 mainly ICs and functions.
Figure 2: shows the whole set power supply system for AKTP01 (A14T02).
Figure 3: shows the system control circuit of AKTP01 (A14T02).
Table 1: A14T02 mainly ICs and functions

Position Type Function Description
N204 TMPA8803/23/21 Micro controller and small signal processor (UOC)
N901 ST24C16-W EEPROM
N701 LA4267 Sound power amplifier
N402 LA78040 Vertical scan output stage circuit
N203 LC4053B/CD4053B AV1/AV2 Switch

2

C-bus controlled IC With combination of micro

Model No: CT-14FES1
Version 1.0

5

BAND1 BAND2

AC150-260V

50/60Hz

Y IN

Cr IN

Cb IN

1

VIDEO IN2

AUDIO IN2

VIDEO IN1

AUDIO IN1

VIDEO OUT

AUDIO OUT

HF TUNER

A101

IF PRE –AMP

V103

V102

KEY BOARD

VIDEO or AUDIO

13

AV1/AV2 SWITH

2

(N203)CD4053

12

V202

V201

(V101)

REMOTE

RECEIVER

A901

14

15

10 11

9

Z101

IF IN

IF IN

SAWF

U/V

L/H

REMOTE INPUT

AUDIO IN

VIDEO IN

SWICH

61

38

41

42

1

2

3

MEMORY

(N901)

ST24C16

SIF TRAPS

Z302,Z304

30 24

32

20 21 19

TOSHIBA UOC

TMPA8803/21/23

58

63

6

5

57

13

HORIZONTAL

DRIVE

V444

16

V. O U T

28

52

51

50

1

T401

5

B

G

R

FIELD OUTPUT

POWER AMP.

N402(LA78040)

Resistance

disturbance

C501、L502

rectification

VD503-VD506

Bridge

Filter

C507

POWER SUPPLY

+300V

V512、V513、V511

T501、VD515

CIRCUIT

、

19V

13V

24V

146V

114V

AUDIO AMPLIFIER

(N701) LA4267

VIDEO

AMPLIFIER

V601

V611

V621

5

HORIZONTAL

OUTPUT

V411

C700

7

CRT

EHT

SCREEN

FBT(T402)

BSC23

SP701

16Ω

SP702

16Ω

FOCUS

Model No: CT-14FES1
Version 1.0

6

SAFETY INSTRUCTION

WARNING: BEFORE EXAMINING AND SERVICING THIS CHASSIS,
READ CAREFULLY THE FOLLOWING SAFETY INSTRUCTIONS.

X-RAY RADIATION PRECAUTION

1. The EHT must be checked every time the receiver is serviced to ensure that the CRT does not emit
X-ray radiation as result of excessive EHT voltage. The nominal EHT for this receiver is 22KV at
zero beam current (minimum brightness) operating at AC 220V. The maximum EHT voltage
permissible in any operating circumstances must not exceed 25KV. When checking the EHT, use
the High Voltage Check procedure in this manual using an accurate EHT voltmeter.

2. The only source of X-RAY radiation in this receiver is the CRT. To prevent X-ray radiation, you
should use the same type of CRT when replacing it.

3. Some components used in this receiver have safety-related characteristics preventing the CRT
from emitting X-ray radiation. For continued safety, replacement component should only be made
after referring the Product Safety notice below.

SAFETY PRECAUTION

1. The high voltage in the TV reaches to 22KV when the TV is in operation. Be more careful during
opening the back cover.

a. The high voltage existing in the TV is very dangerous. Refer servicing to qualified personnel

only.

b. Before removing the high voltage cap. Discharge the anode of the CRT and the chassis in

case of electric shock.
c. Wear a pair of goggles when handling the CRT to avoid broken pieces damaging your eyes.
d. Do not hold the CRT neck in case of causing damage to the CRT.

2. When the power cord needs replacing, use the same one as that provided by AKIRA factory.

3. Voltage exists between the hot and cold ground when TV is in operation. Install a separation
transformer during repairing or connecting to any tester for the sake of safety. The power of the
separation transformer should be beyond rated overall power.

4. When replacing a burnout fuse, use the one with the same specifications as the original.

5. When replacing old wire, wind new one round the shaft to weld. When replacing components with
safety in performance, use the same type as that specified by AKIRA and install it in the former
way.

6. Never place wire near high-temperature or high-voltage components.

SAFETY CAUTIONS FOR PRODUCTS

Many electric and mechanical components in AKTP01 /02 chassis have special safety performances,
which are always neglected. Even if replacing them with some components with the same voltage and
power, you can not get effective protection to X-ray. In the circuit diagram, these special electric

components are indicated by the special mark and on the shadow. When replacing any of them,
use the one with the same specifications as the original’s. Otherwise, it may cause X-ray radiation and
damage to overall safety.

Model No: CT-14FES1
Version 1.0

!

7

CIRCUIT ADJUSTMENTS

GENERAL INFORMATIONS

All adjustment are thoroughly checked and corrected when the receiver leaves the factory. Therefore
the receiver should operate normally and produce proper color and B/W pictures upon installation.
However, several minor adjustments may be required depending on the particular location in which the
receiver is operated.

This receiver is shipped completely in carton. Carefully draw out the receiver from the carton and
remove all packing materials. Power cord into a convenient 220 volts 50 Hz AC two pin power outlet.
Turn the receiver ON. Check and adjust all the customer controls such as BRIGHTNESS, CONTRAST
and COLOUR Controls to obtain natural color or B/W picture.

AUTOMATIC DEGAUSSING

A degaussing coil is mounted around the picture tube so that external degaussing after moving the
receiver is normally unnecessary, providing the receiver is properly degaussed upon installation. The
degaussing coil operates for about 1 second after the power to the receiver is switched ON. If the set is
moved or faced in a different direction, the power switch must be switched off at least 30 minutes in
order that the automatic degaussing circuit operates properly. Should the chassis or parts of the cabinet
become magnetized to cause poor color purity, use an external-degaussing coil. Slowly move the
degaussing coil around the faceplate of the picture tube, the side and front of the receiver and slowly
withdraw the coil to a distance of about 2m before disconnecting it from AC source. If color shading
still persists, perform the COLOUR PURITY ADJUSTMENT and CONVERGENCE
ADJUSTMENTS procedures.

ADJUSTMENT MODE

Item

Measuring
Equipment

Preparation
Before Adj.

Model No: CT-14FES1
Version 1.0

B+ adjustment, TV signal receiving

AKTP01/02 chassis

TV SG (Signal Generator)
Digital multi-meter

The set is turned on
Connect the TV SG to RF input terminal of the set.

ADJUSTMENT PROCEDURE

1. Turn RP551 potentiometer to adjust B+ to specified voltage.

2. Check voltages for video out, vertical out, circuit work and audio power out as follow:-

Voltage (volt)

Tolerance

14 inch 21 inch

8

+B 114 110

Video Out 145 188

Vertical Out 26 26

Circuit Work 13 13

Audio Power Out 19 19

3. TV signal receiving

a. Press MENU key, to select POS.MEMORY item.

Press V+ or V- key, to select SEARCH or AUTOMEMORY item, press P+ key to
start searching.

b. Press P+ or P- key to inspect the set if there is channel skipped, if so, searching again

by SEARCH as above described.

TV system adapting & AV in/output inspection

Item

AKTP01/02 chassis

Measuring
Equipment

SG (with NTSC3.58). User remote controller
Dual trace oscilloscope

±2V

±5V

±1V

±1V

±1V

Preparation
before Adj.

Model No: CT-14FES1
Version 1.0

Input TV and AV signal

9

Inspection procedure

1. Input the TV signal which system is designated in technical specification

2. Switch TV system to the set by pressing SYS key on user remote controller according to the TV
system in SG. The picture and sound must be normal.

3. Press TV/AV key, to select AV input. The picture and sound must be normal

4. AV output inspection. Load a 75Ω resistor to VIDEO output terminal, 1Vp-p video output signal
that is from TV signal should be observed on the oscilloscope. Load a 10K resistor to AUDIO
output terminal, 0.7Vp-p audio output signal that is from TV should be observed on the
oscilloscope.

Focus adjustment

Item

AKTP01/02 chassis

Measuring
Equipment

Preparation
before Adj.

SG

Brightness, contrast and color should be set in standard

Adjustment procedure

1. Receive the cross-hatch pattern signal

2. Turn the focus adjusting VR watching the screen and adjust the vertical line of mark to make the
most thin. Then the focus adj. VR is set as close low voltage side as possible.
Stop the focus adj. VR at the point that focus is a bit worse at once, turn back to the left and then
turn back to the right a little again.

Magnified drawing of part

To be fine

H. line

V. line

Model No: CT-14FES1
Version 1.0

Item

White balance adjustment

AKTP01/02 chassis

10

Measuring
Equipment

Preparation
before Adj.

SG and white balance meter
No.1 service remote controller

Warm up the set for more than 30 min.
Brightness, contrast and color should be set in standard

Adjustment procedure

1. Receive the monoscope pattern signal.

2. Press G (G.DRIVE) key and B (B.DRIVE) key on No.1 service remote controller to select G-DRV
and B-DRV respectively, then press + or – key to adjust the white balance at the directed value
(which is according to the specification of factory’s adjustment)

3. Press R+ or R-, G+ or G- and B+ or B- key respectively to adjust the white balance of low light
until the white balance of high and low light is good

RF. AGC adjustment

Item

AKTP01/02 chassis

Measuring
Equipment

Preparation
before Adj.

SG and digital multi meter
No.5 service remote controller

Connect a digital multi meter to TP101 point on the chassis

Adjustment procedure

1. Receive the color bar signal that is 87.5% modulation and 60dBu level

2. Press RF AGC key on No.5 service remote controller to select RF. AGC adjustment, press + or –
key to adjust the voltage of RF AGC to 6.2±0.05V that is read on the digital multi meter.

Item

Measuring
Equipment

Preparation
before Adj.

Model No: CT-14FES1
Version 1.0

Vertical height, linearity and Hor. position adjustment

AKTP01/02 chassis

SG
No.2 and No.3 service remote controllers

Brightness, contrast and color should be set in standard

11

Adjustment procedure

1. Receive the 5-circles pattern signal that is 50HZ vertical frequency

2. Press V-LINE, V-SIZE, V-CENT and H-CENT key on NO.2 service remote controller
respectively to select the vertical linearity, height, center (position) and horizontal center (position)
adjustment, and then press + or - key to adjust the value of them respectively according to
factory’s specification.

3. Receive the 5-circles pattern signal that is 60HZ vertical frequency

4. Press V-LINE, V-SIZE, V-CENT and H-CENT key on NO.3 service remote controller separately
to adjust the vertical linearity, height, center and horizontal center as above item 3.

OSD position adjustment

Item

AKTP01/02 chassis

Measuring
Equipment

Preparation
before Adj.

No.1 and No.5 service remote controller

Brightness, contrast and color should be set in standard

Adjustment procedure

1. Press D-MODE key on No.1 service remote controller to set the set into design mode adjustment

2. Press or key to select OSD item, press or key to adjust the OSD to the center

position on the screen or press RF AGC key on No.5 service remote controller and press + or –
key to adjust the OSD position.

3. Press D-MODE key again to quit design mode adjustment.

The functions of the set inspection

Item

TD46 chassis

Measuring
Equipment

Preparation
Before Adj.

SG
User remote controller and No.

The set is turned on

Inspection procedure

1. Receive the Philips pattern signal.

2. Press PIC key on user remote controller to call the menu as adjusting picture quality. Adjust color,
brightness, contrast, sharpness and tint (in NTSC) respectively and all adjustment should be right.

3. Press V+ key to increase the sound volume, no distortion heard at maximum level, press V- key to
decrease the sound volume, no sound heard at minimum level.

4. Press POWER key to switch the set into standby status, at mean time the manufactory adjustment
mode is cancelled.

5. Press POWER key again, the set should work in normal receiving mode.

6. Press X (mute), DISP (display), PP and SLEEP key respectively, the relevant function should
be normal.

7. Press S-OUT key on No.5 service remote controller to set default value that stored in E2PROM on
the chassis for product shipment.

Model No: CT-14FES1
Version 1.0

FAULT FINDING TREE, DIAGRAMS AND OVERVIEW

1. Three-None (no raster, no picture, no sound)
This failure is mainly caused by big-power circuit such as power supply, horizontal scanning,
vertical scanning.
The detail checking and repairing steps are as follow.

Model No: CT-14FES1
Version 1.0

12