Akai ctg2501e schematic

AKAI SERVICE MANUAL

25" / 29"

SOLID STATE

Color Television

Receiver

( P AL / SECAM VERSION )

MITSUBISHI I2C IC

This manual is the latest at the time of printing, and does not include the modification which may be made after the printing, by the constant improvment of product.

Document : ___________

SM-37PM

Date :

12-11-2001

Approved by :

Checked by :

(Zeng Shui Hua )

SUPPLY VOLTAGE : AC220V 50Hz > + 10% / -20%

SPECIFICATION

SYSTEM :

CHANNEL L - VHF : H - VHF : UHF :

VIF FREQUENCY : SIF FREQUENCY : CHROMA IF FREQUENCY : INTER-CARRIER FREQUENCY : SCANNING HORIZONTAL :

VERTICAL : ANTENNA INPUT IMPEDANCE :

SM-37PM P. 1

CRT :

PAL - I / I

4 - 13

21 - 69

38.9

32.9

34.47

6.0

PAL - BG

2 - 4

5 -12

21 - 69

38.9

33.4

34.47

5.5

PAL - I

(UK)

21 -69

39.5

33.5

35.07 6

PAL - SECAM -

BG / DK

1 - 5

6 - 12

21 - 69

38.0

31.5 32.5

33.57 33.57

6.5 5.5

PAL - SECAM -

BG / DK

( HYPER )

1 - 5

6 - 12

21 - 69

38.9

32.4 33.4

34.47 34.47

5.5 6.5 15625 LINE

50 Hz

75 OHM

25" 29"

PAL - BG

( HYPER )

E2 - S10 E5 - S41

E21 - E69

38.9

33.4

34.47

5.5

PAL - BG

( CATV )

E2 - S2

E5 - S20

E21 - E69

38.9

33.4

34.47

5.5

SECAM - L

1 - Q

21 - 69

38.9

32.4

34.47

6.5

L'

FB - FC

32.7

39.2

6.5

CH CH

CH MHz MHz MHz MHz

ITEMS OF MEASUREMENT

STANDARD

UNIT

VIDEO SENS. AT S/N 30db

L - VHF

H - VHF

UHF

SOUND SENS. AT S/N 30db

L - VHF

H - VHF

UHF AGC CHARACTER SELECTIVITY -1.5 MHz

+ 8 MHz COLOR SENS. COLOR LOCK - IN RANGE VERTICAL LOCK - IN RANGE HORIZONTAL LOCK - IN RANGE MAX BRIGHTNESS MAX OUTPUT POWER OUTPUT POWER AT 10% THD

< 57 < 57 < 60

< 42 < 42 < 48

> 60 > 35

> 40 < 45 > +300 > 6 > 400 > 100 > 4.5 > 3.5

dbuv dbuv dbuv

db db

db

dbuv

Hz Hz Hz

cd/m2

W

W BUZZ AFC RANGE

MIN. VOL HUM RESOLUTION HORIZONTAL

VERTICAL

LINEARITY DISTORTION VERTICAL

HORIZONTAL RASTER DISTORTION REMOTE CONTROL DISTANCE

ANGLE

POWER CONSUMPTION ( AT NORMAL CONDITION ) POWER CONSUMPTION ( AT MAX. CONDITION )

CONVERGENCE DISLOCATION AT AREA "A"

AREA "B"

( see fig.1 )

< -40 > +1

> -0.5 < 20 > 300

> 400 < 10

< 10 < 5 > 5

> +15 < 120

< 150 < 0.4

< 0.8

db

MHz MHz

mV

LINES LINES

% %

%

METER

DEGREE

WATTS WATTS

% %

H

VIDEO INPUT LEVEL : 1.0V P-P + 3dB AUDIO INPUT LEVEL : 0.5V RMS + 3dB

Fig.1

A

SM-37PM P. 2

B

ALIGNMENT INSTRUCTION

I. PLEASE READ BEFORE ATTEMPTING SERVICE

1. Never disconnect any leads while receiver is in operation.

2. Disconnect all power before attempting any repairs.

3. Do not short any portion of the circuit while power is on.

4. For safety reasons, all parts replaced should be identical, ( for parts and part numbers see parts list ).

5. Before alignment the set must be pre-heated for 30 minutes or more and erase magnetism thoroughly from CRT front chassis frame by erase coil. ( Except IF, SYNC, COLOR, SECAM, B+, SOUND )

II.

TEST EQUIPMENT

1. Colour Bar, Dot, Cross Hatch Generator

2. DC Power Supply

3. Oscilloscope

4. Vacuum Tube Voltmeter

5. Volt Ohmmeter

6. High Voltage Meter

7. Ampere Meter ( 0.5 Class, DC 3mA Max )

8. Demagentizing Coil

9. Philips Pattern Generator

10. High Pot Tester

III. FACTORY ADJUSTMENT : See table 1- 4

1. Press REMOTE FACTOR Y ON button.

2. Press REMOTE FACTO RY button.

3. Press REMOTE UP or DOWN button select item.

4. Press REMOTE value (+) (-) button,adjust the value.

5. REMOTE DIALOG CENTRE button can turn off factory mode function. REMARK : NO this factory on Normal remote control .

IV.B+ ADJUSTMENT

1. Connect a digital voltmeter between the W234 and Ground.

2. Press REMOTE Picture button.

3. Press REMOTE UP/DOWN and value (-) button set Brigntness,contrast,color to minimum.

4. Adjust Screen Volume on FBT Until the picture can just been seen

5. Adjust VR901 and obtain a reading of 143V +1V (DC).

.

V. AGC ALIGNMENT

1. Receive CH69 ( UHF ) and input field strength. (60dB in put signal)

2. Connect a digital voltmeter between the TUNER AGC TERMINAL and Ground.

3. Press REMOTE AGC button.

4. Press REMOTE value (+) (-) button adjust value to (0) and then adjust AGC take over value obtain drop down 0.4V. (DC) REMARK : ( 1/ The drop down voltage should be more than and tends to 0.4V ) ( 2/ No observable noise can be seen )

SM-37PM P. 3

VI. SOUND TRACKING ALIGNMENT

1. Receive a gray scale pattern.

2. Connect a oscilloscope and monitor IC109 TDA3857 PIN 15 and Ground.

3. Adjust T101 to obtain the waveform Fig.6.

4. Conect a Voltage meten and monitor IC 104 TDA9801 PIN 15 and gorund.

5. Adjust T101 obtain 5V+0.1V (DC).

Fig.6

Remark: All frequency of Marker points are +0.2% tolerance.

VII. EAST - WEST CORR ECTION ADJUSTMENT

1) Receive a crosshatch and center cross pattem.

2) Set the Brightness,contrast to middle position.

3) Press REMOTE EW-Par/wid,EW-trap button,Press REMOTE VALUE (+) (-) button adjust Value to normal regular picture.

4) Press REMOTE WE-width button,Press REMOTE value (+) (-) button adjust value to proper horizontal width ( 90% + 2% )

VIII. HORIZONT AL SHIFT ADJUSTMENT

1. Receive Monoscope Pattern input signal 70dB +10dB.

2. Press REMOTE H-shirt button.

3. Press REMOTE value (+) (-) button adjust value to obtain the picture at center +2mm. ( Specification show in Fig.8 )

IX. VERTICAL LINEARTY ADJUSTMENT

1) Receive a crosshatch and center cross pattem.

2) Set the Brightness,contrast to middle position.

3) Press REMOTE V-SIope,S-Correction button,Press REMOTE Value (+) (-) button adjust value to normal regular picture.

4) Press REMOTE V-Shift button,Press REMOTE Value (+) (-) button adjust value to obtain the picture at center.

X. VERTICAL AMPL ADJUSTMENT

1. Receive the Monoscope Pattern.

2. Press REMOTE V-ampl button.

3. Press REMOTE value (+) (-) button adjust value to obtain a normal picture.

XI. WHITE BALANCE ALIGNMENT STEP

( Degauss the picture by degaussing coil if necessary )

1. Receive a grey scale pattern

2. Connect a oscilloscope and monitor CN101 pin"3"and ground.

3. Press REMOTE picture button.

4. Press REMOTE UP/DOWN and value (-) button set the brightness,contrast, to middle position.

5. Ajust screen volume on FBT unitl the waveform to 2.5V+/-0.25V DC see fig.7.

6. Press REMOTE sub bri button.

7. Press REMOTE value (+) (-) button adjust value to (18).

8. Receive a black and white pattern

9. Press REMOTE with bal button.

10. Press REMOTE UP/Down and value (+) (-) button adjust blue str value to(0).

11. Press REMOTE picture button.

12. Press REMOTE UP/Down and Value(+) (-) button set the brightness and color to minimun position. contrast to MAX position.

13. Press REMOTE pt r.g.b.button.

14. Press REMOTE UP/Down and value (+) (-) button adjust the white balance.(9300

o

k)

SM-37PM P. 4

OV (DC)

2.5V+/-0.25V (DC)

fig.7

SM-37PM P. 5