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3-2

ADJUSTMENT INSTRUCTIONS

1. APPLICATION RANGE

These adjustment instructions is applied to MV-033A chassis.

2. Notes

2.1. Because this is a cold chassis, it is not necessary to use an

isolation transformer.
But operate it using a transformer between the power
supply line and chassis input to prevent electric shock and
to protect the test instrument.

2.2. All adjustment must be done in correct sequence.

However, for the better productivity, it can be changed in
pre-permitted range.

2.3. Environment conditions : If not specified, it must be done in

following conditions.

1) Temperature  : 25

c

!

c

C

2) Humidity 

: 65 % 

!

10 %

2.4. Power supply of a SET which is adjusted is AC110-240V,

50/60Hz.(EU model : AC230V,50HZ)

2.5. If not specified, the receiver must be operated for more

than 20 minutes prior to the adjustment.

2.6. Signal

Receive the standard color signal. (65dB 

1dB uV)

LG standard signal means the digital pattern PAL-B/G
05CH.

3. DECK Line Adjustment.(VCR DECK Part)

3.1. P2/P3 Pre-Adjustment

3.1.1. Necessary Instrument

1) PAL SP Normal TAPE
2) OSCILLOSCOPE 
3) 10:1 PROBE  : 2 PIECES
4) SPECIAL NUT DRIVER (for P2/P3 Control)

3.1.2. Adjustment

1) Play the PAL standard Tape(SP).

2) Connect to J261(H/SW) the OSCILLOSCOPE(CH-1) on

the MAIN1 PCB.

3) Connect to J219(RF) the OSCILLOSCOPE(CH-2) on the

MAIN1 PCB.

4) With observing the RF envelope waveform, adjust P2, P3

until it becomes the waveform C. 

5) Check the envelope waveform is in the maximum size by

pressing the TRK UP(+).

3.2. CTL/AUDIO LEVEL ADJUSTMENT

3.2.1. NECESSARY INSTRUMENT

1. CTL TAPE
2. PAL SP Standard TAPE(for Audio level adjustment)
3. OSCILLOSCOPE
4. 10:1 PROBE : 2 PIECES
5. RMS METER(for Audio level adjustment)

3.2.2. CTL ADJUSTMENT

THIS ADJUSTMENT MUST BE DONE WHEN THE
UNCONTROLLED DECK IS WAREHOUSED.

1) Connect the OSCILLOSCOPE to J101(CTL)
2) After playing the CTL control tape, make sure the CTL

waveform range is From 1.5 :1 to 2.5 : 1.
If it is out of range , adjust CTL waveform to the following
procedures.

¤

If is over 2.5 :1, lower the  head height.

After turning the height adjust screw counter-clockwise
to adjust its level from 1.5 : 1 to 2 : 1. Check the tape
location at P4.   Readjust the TILT.(2:1)

¤Ł

If is under 1.5:1, heighten the head height.

After turning the height, adjust the screw clockwise to
adjust its level from 2 : 1 to 2.5 : 1. Check the tape
location of P4.   Readjust the TILT.(2:1)

3) Play the standard tape and adjust the azimuth screw right

and left by using the oscilloscope and level-meter to
maximize the audio sound.
Adjust the azimuth screw & the height adjust screw at the
same time because they have mutual relationship.
(Check CTL again after the adjustment)
*A/C head adjustment order
Height adjust screw->check the TILT->azimuth screw->
check CTL

P2

<A> P2 POST ADJUSTMENT

P3

D

<B> P3 POST ADJUSTMENT

D

<C> The Waveform after adjustment

TAKE

- UP

REEL

AZIMUTH ADJUST SCEW

CAPSTAN

T/UP ARM

SUPPLY

REEL

DRUM

P2

P3

FE HEAD

P1

TENTION ARM

P4

P0

TAKE

- UP

REEL

AZIMUTH ADJUST SCEW

CAPSTAN

T/UP ARM

SUPPLY

REEL

DRUM

P2

P3

FE HEAD

P1

TENTION ARM

P4

P0

TAKE

- UP

REEL

AZIMUTH ADJUST SCEW

CAPSTAN

T/UP ARM

SUPPLY

REEL

DRUM

P2

P3

FE HEAD

P1

TENTION ARM

P4

P0

X-Value Fixed Screw

X-Value Adjustment Hole

Tilt Adjustment screw

Height Adjustment Screw

PINCH - ROLLER

<Fig1> Adjustment Position

<Fig2> P2/ P3 Adjustment Waveform

1

2

CTL WAVEFORM

1

2

CTL WAVEFORM

1

2

CTL WAVEFORM

<Fig3>

Summary of Contents for Multiplex 72

Page 1: ... TV Triple Combi TV SERVICE MANUAL CAUTION BEFORE SERVICING THE CHASSIS READ THE SAFETY PRECAUTIONS IN THIS MANUAL CHASSIS MV 033A MODEL Multiplex 72 website http biz LGservice com e mail http www LGEservice com techsup html SERVICE MANUAL MODEL Multiplex 72 LG Electronics inc ...

Page 2: ...72 CONTENT SAFETY INSTRUCTIONS 1 2 SERVICING PRECAUTIONS 1 4 SPECIFICATION 1 5 DESCRIPTION OF CONTROLS 1 8 SECTION 1 SUMMARY ON OFF STOP PLAY OPEN CLOSE STOP EJECT PLAY REC ITR DVD TRK COPY VCR REC PM TV Triple Combi TV SERVICE MANUAL ...

Page 3: ...er details see the VCR Operation section 4 DVD BUTTONS controls a LG DVD player For further details see the DVD Operation section 5 RESET When Communicator does not work reset the Communicator by pressing the reset point with sharp one 6 POWER switches the set on from standby or off to standby 7 NUMBER BUTTONS switches the set on from standby or directly select a number 8 MENU selects a menu 9 D E...

Page 4: ...enera tor To charge the communicator do the followings 1 In first use 20 rotation of the handle in the arrow direction as picture below waiting for one minute 20 rotation again waiting for one minute again 20 rotation again beginning to use 2 In usual use 20 or 25 rotation resuming to use Note Do not rotate the handle too rapidly for the protection of the communicator TVCR DVD RESET EJECT PSM SSM ...

Page 5: ...ARTMENT Inserts a video cassette tape here 8 STOP EJECT stops the tape during playback or recording or ejects the tape 9 D D E E Programme Up Down selects a programme or a menu item switches the set on from standby F F G G Volume Down Up adjusts the volume adjusts menu settings 10 REC ITR starts a manual recording or instant timer recording 11 POWER r r I switches the set on from standby or off to...

Page 6: ...level adjustment 3 OSCILLOSCOPE 4 10 1 PROBE 2 PIECES 5 RMS METER for Audio level adjustment 3 2 2 CTL ADJUSTMENT THIS ADJUSTMENT MUST BE DONE WHEN THE UNCONTROLLED DECK IS WAREHOUSED 1 Connect the OSCILLOSCOPE to J101 CTL 2 After playing the CTL control tape make sure the CTL waveform range is From 1 5 1 to 2 5 1 If it is out of range adjust CTL waveform to the following procedures If is over 2 5...

Page 7: ...61 on the main PCB and trigger in setting the VOL DIV to 1V range 3 Connect the oscilloscope CH 2 to video out C571 on the main PCB and set the VOL DIV to 500mV range 4 Set the TIME DIV of oscilloscope to 50us range 5 If press P CHECK of SVC Remote control A PG is appeared in the display and PG adjustment signal become 412uS 100uSec 4 ASSEMBLY LINE ADJUSTMENT 4 1 DVCO adjustment 1 This is for adju...

Page 8: ...WR WG WB 800 4 6 Deflection data adjustment 4 6 1 Preparation 1 At adjustment mode IN START button on remote control of adjustment changed to LINE SVC 2 mode to adjust the deflection 2 Press Channel UP DOWN button for desirous function adjustment 3 Press Volume UP DOWN button to adjust the data 4 Tune the TV set to receive a Digital pattern PAL EU05CH NTSC 13CH 4 6 2 Deflection setting data adjust...

Page 9: ...Amplitude Vertical Linearity S Correction Vertical Shift Horizontal Shift East West Width East West Trapezium East West Parabola East West Symmetric East West corner Bow Correction Quadratic Angle Correction Linear 0050 00CF 0025 00BF 0000 009F 0600 0900 0000 003F 0400 0EFF 0700 08FF 06E0 0840 06A0 0AFF 0790 08E0 256 255 256 255 00A1 00FB 00D0 0738 0017 0B04 07F8 07B0 0840 0825 0000 0000 160 0 32 ...

Page 10: ...AUSSING WITH DEGAUSSING W O TILT NORMAL MODEL EXCEPT AUSTRALIA WITH TILT FLAT AUSTRALIA NORMAL MODEL B G I DK L L B G I DK M PAL N M M REMARK 21 Option OPTION TSS Turbo search DUAL Dual Save V CUR Vol HOTEL M VOL MONO CODE 0 1 0 1 0 1 0 1 1 100 0 1 FUNCTION WITHOUT TURBO SEARCH WITH TURBO SEARCH NO SAVE DUAL SOUND CONDITION SAVE DUAL SOUND CONDITION NORMAL VOLUME CURVE WITHOUT HOTEL OPTION WITH HO...

Page 11: ...3 7 BLOCK DIAGRAM ...

Page 12: ...3 8 ...

Page 13: ...3 9 ...

Page 14: ...mp Flicker Check Replace Deck Assy NO Check Replace Mode Switch P02 No Play Of VCR Open Close Control Check Replace The DVD Loader NG OK No Play Of DVD Check the voltage of P751A pin1 3 6 3 3V 12V 5 3V Bad Disc No Disc On the Menu Check the Disc Condition Check the Regional Code On Disc Check The VCR SMPS Board NO OK 3 10 ...

Page 15: ...701 Relay Check the power CTL of IC01 Pin27 Check Waveform of P821 Pin9 H out Check Q401 collector waveform Check T402 voltage Check replace IC501 Check replace Q401 Check the in out of IC801 Check the D801 Check replace RL701 OK NO OK OK Yes No No No No OK Open Go to No Power Block No ...

Page 16: ...em in MENU Check the waveform of PIN 4 12 IC851 Check the waveform of PIN 27 28 IC601 Check the Freq of X600 X tal CheckVcc replace IC851 OK NO NO OK Check replace P500 Connector OK Check replace Tuner Audio Line OK Check replace VCC IIC line NO ...

Page 17: ...heck the Waveform of IC501 Pin42 43 44 Check FR901 FR401 Check FBT T402 Check the Heater Volt 6 0V 6 4V Check The Main Power Board OK OK Not OK Check Replace IC501 Not OK Check VCC of IC501 Pin 3 15 25 45 54 3 3V or 5V OK Not OK ...

Page 18: ...Flicker Check Replace DeckAssy NO Check Replace Mode Switch P02 No Play Of VCR Open Close Control Check Replace The DVD Loader NG OK No Play Of DVD Check the voltage of P751A pin1 3 6 3 3V 12V 5 3V Bad Disc No Disc On the Menu Check the Disc Condition Check the Regional Code On Disc Check The VCR SMPS Board NO OK ...

Page 19: ...P NO 3854VA0122A S1 1 2 2004 2 26 ...

Page 20: ...P NO 3854VA0122A S1 2 2 2004 2 26 ...

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