Memorex MT1098 Schematic

MT1098

SERVICE MANUAL

COLOR TELEVISION RECEIVER

ORIGINAL

MFR’S VERSION B

Design and specifications are subject to change without notice.

SERVICING NOTICES ON CHECKING

As for the places which need special attentions, they are indicated with the labels or seals on the cabinet, chassis and parts. Make sure to keep the indications and notices in the operation manual.

2. AVOID AN ELECTRIC SHOCK

There is a high voltage part inside. Avoid an electric shock while the electric current is flowing.

3. USE THE DESIGNATED PARTS

The parts in this equipment have the specific characters of incombustibility and withstand voltage for safety. Therefore, the part which is replaced should be used the part which has the same character. Especially as to the important parts for safety which is indicated in the circuit diagram or the table of parts as a mark, the designated parts must be used.

PUT PARTS AND WIRES IN THE

4. ORIGINAL POSITION AFTER ASSEMBLING OR WIRING

There are parts which use the insulation material such as a tube or tape for safety, or which are assembled in the condition that these do not contact with the printed board. The inside wiring is designed not to get closer to the pyrogenic parts and high voltage parts. Therefore, put these parts in the original positions.

5. TAKE CARE TO DEAL WITH THE CATHODE-RAY TUBE

In the condition that an explosion-proof cathoderay tube is set in this equipment, safety is secured against implosion. However, when removing it or serving from backward, it is dangerous to give a shock. Take enough care to deal with it.

6. AVOID AN X-RAY1. KEEP THE NOTICES

Safety is secured against an X-ray by considering about the cathode-ray tube and the high voltage peripheral circuit, etc. Therefore, when repairing the high voltage peripheral circuit, use the designated parts and make sure not modify the circuit. Repairing except indicates causes rising of high voltage, and it emits an X-ray from the cathoderay tube.

7.PERFORM A SAFETY CHECK AFTER SERVICING

Confirm that the screws, parts and wiring which were removed in order to service are put in the original positions, or whether there are the portions which are deteriorated around the serviced places serviced or not. Check the insulation between the antenna terminal or external metal and the AC cord plug blades. And be sure the safety of that.

(INSULATION CHECK PROCEDURE)

Unplug the plug from the AC outlet.

Remove the antenna terminal on TV and turn on the TV.

Insulation resistance between the cord plug terminals and the eternal exposure metal [Note 2] should be more than 1M ohm by using the 500V insulation resistance meter [Note 1].

If the insulation resistance is less than 1M ohm, the inspection repair should be required.

[Note 1]

If you have not the 500V insulation resistance meter, use a Tester.

[Note 2]

External exposure metal: Antenna terminal

Earphone jack

HOW TO ORDER PARTS

Please include the following informations when you order parts. (Particularly the VERSION LETTER.)

1. MODEL NUMBER and VERSION LETTER The MODEL NUMBER can be found on the back of each product and the VERSION LETTER can be found at the end of the SERIAL NUMBER.

2. PART NO. and DESCRIPTION You can find it in your SERVICE MANUAL.

IMPORTANT

Inferior silicon grease can damage IC's and transistors. When replacing an IC's or transistors, use only specified silicon grease (YG6260M). Remove all old silicon before applying new silicon.

A1-1

CONTENTS

SERVICING NOTICES ON CHECKING ..........................................................................................................

HOW TO ORDER PARTS................................................................................................................................

IMPORTANT....................................................................................................................................................

CONTENTS......................................................................................................................................................

GENERAL SPECIFICATIONS.........................................................................................................................

DISASSEMBLY INSTRUCTIONS

1. REMOVAL OF ANODE CAP.................................................................................................................

2. REMOVAL OF DEFLECTION YOKE.....................................................................................................

3. REMOVAL AND INSTALLATION OF FLAT PACKAGE IC....................................................................

SERVICE MODE LIST .....................................................................................................................................

CONFIRMATION OF HOURS USED..............................................................................................................

WHEN REPLACING EEPROM (MEMORY) IC...............................................................................................

ELECTRICAL ADJUSTMENTS.......................................................................................................................

MAJOR COMPONENTS LOCATION GUIDE..................................................................................................

BLOCK DIAGRAM...........................................................................................................................................

PRINTED CIRCUIT BOARDS

MAIN/CRT..............................................................................................................................................

SCHEMATIC DIAGRAMS

MICON/TUNER.....................................................................................................................................

CHROMA ..............................................................................................................................................

DEFLECTION/CRT................................................................................................................................

POWER.................................................................................................................................................

AV/SOUND ...........................................................................................................................................

WAVEFORMS..................................................................................................................................................

MECHANICAL EXPLODED VIEW..................................................................................................................

MECHANICAL REPLACEMENT PARTS LIST...............................................................................................

ELECTRICAL REPLACEMENT PARTS LIST.................................................................................................

A1-1 A1-1 A1-1 A2-1 A3-1~A3-4

B1-1 B2-1 B3-1, B3-2 C-1 C-1 C-1 D1-1~D2-1 D3-1 E-1, E-2

F-1~F-4

G-1, G-2 G-3, G-4 G-5, G-6 G-7, G-8 G-9, G-10 H-1, H-2 I-1 J1-1 J2-1, J2-2

A2-1

GENERAL SPECIFICATIONS

G-1.Outline of the Product

9 inch(222.8mmV):Measured diagonally Color CRT 90 degree deflection

G-2.Broadcasting System

US System M G-3.Color System NTSC PAL SECAM or Monochrome signal G-4.NTSC Playback(PAL 60Hz) Yes No Not Applicable G-5.NTSC 3.58+4.43/PAL60Hz Yes No Not Applicable

G-6.Antenna Input Impedance

VHF/UHF 75 ohm unbalanced G-7.Tuner and Receiving Contactless Electric tuner 1Tuner System

2Tuner System

channel Tuner Oscar(W/O HYPER) Oscar(W/ HYPER)

France CATV) Others

Receiving channel

(USA) 2-69 , 4A , A-5~A-1 , A~I , J~W , W+1~W+84

Tuning System

Frequency syn. Voltage syn. Others

G-8.Preset Channel

-- channels

G-9.Intermediate Frequency

Picture(fP) 45.75MHz MHz MHz

Sound (fS) 41.25 MHz MHz MHz

fP-fS 4.50 MHz MHz MHz G-10.Stereo/Dual TV Sound

Yes( NICAM GERMAN USA JAPAN) No G-11.Tuner Sound Muting Yes No G-12.Power Source DC 12 V G-13.Power Consumption: 35 W at DC 12 V

Stand by: 1 W at DC 12 V Per Year: -- kWh / Year

G-14.Dimensions(Approx.)

232 mm(W) 289 mm(D) 224 mm(H)

G-15.Weight(Approx.) Net : 5.0 kg ( 11.0 lbs)

Gross: 6.0 kg ( 13.2 lbs)

G-16.Cabinet Material

Cabinet Front: PS 94HB DECABROM

ABS 94V2 NON-DECA

94V0

Back Panel: PS 94HB DECABROM

ABS 94V2 NON-DECA

94V0

G-17.Protector: Power Fuse

A3-1

GENERAL SPECIFICATIONS

G-18.Regulation

Safety

UL CSA SAA SI CE SEV

BS NF NEMKO FEMKO DEMKO IEC65

SEMKO NZ HOMOLO SABS CNS SISIR

NOM AS3159 DENTORI UNE GOST NONE

Radiation

FCC DOC FTZ PTT CE SEV

SABA SI NF NZ HOMOLO UNE

CNS CISPR13 DENTORI AS/NZS NONE

X-Radiation

PTB DHHS HWC DENTORI NONE G-19.Temperature : Operation 5 ºC ~ 40 ºC

Storage -20 ºC ~ 60 ºC

G-20.Operating Humidity Less than 80 %RH G-21.Clock and Timer

Sleep Timer Yes Max 120 Min.( 10 Min. Step) No On/Off Timer Yes Programs No

Wake Up Timer Yes Programs No G-22.Timer back up Time: More than -- Minutes (at Power Off Mode) G-23.Terminals

VHF/UHF Antenna Input Din Type F-Type France Type Front Video Input (RCA ø8.3) Front Audio Input (RCA ø8.3)

Rear Video Input1 (RCA ø8.3) Rear Audio Input1 (RCA ø8.3)

Rear Video Input2 (RCA ø8.3) Rear Audio Input2 (RCA ø8.3)

Rear Video Output (RCA ø8.3) Rear Audio Output (RCA ø8.3)

21 Pin DC Jack(Center +) Ear Phone Jack(ø3.5) Head Phone Jack(ø3.5) AC Outlet Ext Speaker(ø3.5) Diversity S Input(Front) S Input(Rear)

G-24.Indicator : Power Stand By On Timer NONE

( ) ( ) ( )

G-25.Display

On Screen Display

Menu Clock Set( 12H 24H)

CH Set TV/CATV

Auto Ch Memory

ADD/Delete Picture Language V-Chip

Control Level Sound Brightness Contrast

Color Tint(NTSC Only) Sharpness Tuning Bass Treble

Balance Back Light Stereo,Audio Output,SAP Mid Night Theater Stereo,Audio Output GAME Picture Menu AV Channel Clock Hotel Lock Sleep Timer Sound Mute Pin Code

A3-2

GENERAL SPECIFICATIONS

G-26.OSD Language

Eng Ger Fre Spa Ita Por Jpn

OSD Language Setting

Eng Ger Fre Spa Ita Por Jpn Not Applicable

G-27.Speaker NONE

Layout Front Side Bottom Size/Quantity inches x pcs Imp. ohm Power Max. W

10 % W (Typical)

G-28.EXT Speaker : Yes No

Imp. 8 ohm Power Max. 1.2 W

10 % 0.8 W (Typical)

G-29.Carton

Master Carton: Need No Need

Content: ---- Set Material: ---- / ---- Corrugated Carton Dimensions: ---- mm(L) ---- mm(W) ---- mm(D) Description of Origin Yes No

Gift Box

Material Single/Brown Corrugated Carton ( with Photo Label)

Double/White Corrugated Carton ( with Photo Label)

Double Full Color Carton W/Photo Dimensions: 294 mm(W) 348 mm(D) 295 mm(H) Design: As Per Buyer 's Description of Origin: Yes No Drop Test Natural Dropping At 1 Corner / 3 Edges / 6 Surfaces

Height 25cm 31cm 46cm 62cm 80cm

Container Stuffing: 2,140 Sets / 40' container

G-30.Accessories

Owner's Manual ( W/Guarantee Card) [English/Spanish]

AC Plug Adapter Channel film Battery (UM- x ) Remote Control Unit Safety Tip Toll Free Insert Sheet Guarantee Card Audio-Video Cord (RCA) Registration Card Warning Sheet Quick Set-Up Sheet Schematic Diagram Information Sheet U/V Mixer 75 ohm Coaxial Cable ( Single Shield Double Shield) 300 ohm to 75 ohm VHF Antenna Adaptor 21pin Cable Car Cord Rod Antenna

One Pole Two Pole( F-Type Din Type France Type)

Loop Antenna ( F-Type Din Type France Type)

G-31.Other Features

Auto Degauss Auto CH Memory Auto Shut Off Picture Me nu SAP Comb Filter CATV(181CH) Game Position Anti-Theft Mid Night Theater Rental Closed Caption V-Chip

A3-3

GENERAL SPECIFICATIONS

G-32.Switch

Front

Power Channel Up/Reset Volume Up/Set+ System Select Channel Down/Enter Volume Down/SetMain Power SW Sub Power Menu TV/AV Picture

Rear

AC/DC TV/CATV Selector Degauss Main Power SW

G-33.Magnetic Field

BV: +0.45G BV: +0.35G BV: +0.25G BH: 0.18G BH: 0.30G BH: 0.30G BV: -0.15G BV: -0.25G BV: -0.50G BH: 0.15G BH: 0.15G BH: 0.30G

G-34.Remote Control Unit: RC-CX

Power Source: D.C 3 V Battery UM - 4 x 2 Total 34 Keys

CTV Power TV/AV 0 Volume Up 1 Volume Down 2 CH Up 3 CH Down 4 Sleep 5 Call 6 Reset 7 Enter 8 Menu 9 Set + Quick View Set -

VP POWER Still Play Repeat Stop ATR F.FWD Tr+ Rew Tr-

A3-4

DISASSEMBLY INSTRUCTIONS

1. REMOVAL OF ANODE CAP

Read the following NOTED items before starting work.

After turning the power off there might still be a potential

voltage that is very dangerous. When removing the Anode Cap, make sure to discharge the Anode Cap's potential voltage. Do not use pliers to loosen or tighten the Anode Cap

terminal, this may cause the spring to be damaged.

REMOVAL

Follow the steps as follows to discharge the Anode Cap.

(Refer to Fig. 1-1.)

Connect one end of an Alligator Clip to the metal part of a flat-blade screwdriver and the other end to ground. While holding the plastic part of the insulated Screwdriver, touch the support of the Anode with the tip of the Screwdriver. A cracking noise will be heard as the voltage is discharged.

GND on the CRT

INSTALLATION

Clean the spot where the cap was located with a small

1. amount of alcohol. (Refer to Fig. 1-3.)

Location of Anode Cap

NOTE

Confirm that there is no dirt, dust, etc. at the spot where the cap was located.

Arrange the wire of the Anode Cap and make sure the

2. wire is not twisted. Turn over the Rubber Cap. (Refer to Fig. 1-4.)

Fig. 1-3

CRT

Support

Alligator Clip

Screwdriver

GND on the CRT

Fig. 1-1

Flip up the sides of the Rubber Cap in the direction of the

2. arrow and remove one side of the support.

(Refer to Fig. 1-2.)

Rubber Cap

CRT

Support

Fig. 1-2

3. After one side is removed, pull in the opposite direction to remove the other.

NOTE

Take care not to damage the Rubber Cap.

Fig. 1-4

4. Insert one end of the Anode Support into the anode button, then the other as shown in Fig. 1-5.

Support

CRT

Fig. 1-5

5.6.Confirm that the Support is securely connected. Put on the Rubber Cap without moving any parts.

B1-1

DISASSEMBLY INSTRUCTIONS

2. REMOVAL OF DEFLECTION YOKE

(Refer to Fig. 2-1)

Loosen the screw 1.

Remove the Convergence • Purity Magnet in the direction of arrow (A).

Remove the 3 Wedges.

Remove the Deflection Yoke in the direction of arrow (A).

INSTALLATION

Install new Deflection Yoke in reverse steps of REMOVAL.

NOTE

After adjusting the purity and the convergence, fix the screw 1 and lock the wedges.

Wedge

(A)

Deflection Yoke

Convergence • Purity Magnet

Fig. 2-1

B2-1

DISASSEMBLY INSTRUCTIONS

REMOVAL AND INSTALLATION OF FLAT PACKAGE IC

REMOVAL

Put the Masking Tape (cotton tape) around the Flat

1. Package IC to protect other parts from any damage.

(Refer to Fig. 3-1.) NOTE

Masking is carried out on all the parts located within 10 mm distance from IC leads.

When IC starts moving back and forth easily after

3. desoldering completely, pickup the corner of the IC using a tweezers and remove the IC by moving with the IC desoldering machine. (Refer to Fig. 3-3.)

NOTE

Some ICs on the PCB are affixed with glue, so be careful not to break or damage the foil of each IC leads or solder lands under the IC when removing it.

Blower type IC desoldering machine

Masking Tape (Cotton Tape)

Heat the IC leads using a blower type IC desoldering

machine. (Refer to Fig. 3-2.)

NOTE

Do not add the rotating and the back and forth directions force on the IC, until IC can move back and forth easily after desoldering the IC leads completely.

Blower type IC desoldering machine

Fig. 3-1

Tweezers

Fig. 3-3

Peel off the Masking Tape.4. Absorb the solder left on the pattern using the Braided

5. Shield Wire. (Refer to Fig. 3-4.)

NOTE

Do not move the Braided Shield Wire in the vertical direction towards the IC pattern.

Braided Shield Wire

Soldering Iron

Fig. 3-2

IC pattern

Fig. 3-4

B3-1

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