Daewoo AMI-921DPR, AMI-921DP User Manual

Service Manual

MINI COMPONENT SYSTEM

Model :

AMI-921DP / 921DPR

DAEWOO ELECTRONICS CO., LTD.

TABLE OF CONTENTS

SAFETY PRECAUTIONS ................................................................................................. 2

ADJUSTMENTS............................................................................................................. 4

EXPLODED VIEW AND PARTS LIST ................................................................................ 7

WIRING DIAGRAM ..................................................................................................... 9

BLOCK DIAGRAM ...................................................................................................... 10

SCHEMATIC DIAGRAM ............................................................................................... 11

POWER / AMP ...................................................................................................................................11

CD ...................................................................................................................................................12

TUNER ...............................................................................................................................................13

TAPE .................................................................................................................................................16

CONTROL .........................................................................................................................................17

PCB PATTERN LAYOUT ................................................................................................. 18

SAFETY PRECAUTIONS

WARNING

THIS APPLIANCE TO RAIN OR MOISTURE.

CAUTION :

TO PREVENT ELECTRIC SHOCK, DO NOT USE THIS POLARIZED AC PLUG WITH AN EXTENSION CORD, RECEPTACLE OR OTHER OUTLET UNLESS THE BLADES CAN BE FULLY INSERTED TO PREVENT BLADE EXPOSURE.

THIS UNIT EMPLOYS A LASER. ONLY QUALIFIED SERVICE PERSONNEL SHOULD REMOVE THE COVER OR ATTEMPT TO SERVICE THIS DEVICE DUE TO POSSIBLE EYE INJURY.

CAUTION :

OTHER THAN THOSE SPECIFIED HEREIN MAY RESULT IN HAZARDOUS RADIATION EXPOSURE.

CAUTION :

PLUG TO WIDE SLOT, FULLY INSERT.

ATTENTION :

LA LAME LA PLUS LARGE DE LA FICHE DANS LA BORNE CORRESPONDANTE DE LA PRISE ET POUSSER JUSQU'AU FOND.

: TO PREVENT FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE

CAUTION

RISK OF ELECTRIC SHOCKS

DO NOT OPEN

TO REDUCE THE RISK IF ELECTRIC SHOCK, DO NOT REMOVE COVER (OR BACK). NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

THIS SYMBOL IS INTENDED TO ALERT THE USER TO THE PRESENCE OF UNINSULTED "DANGEROUS VOLTAGE"

WITHIN THE PRODUCT'S ENCLOSURE THAT MAY BE

SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK TO PERSONS.

THIS SYMBOL IS INTENDED TO ALERT THE USER TO THE PRESENCE OF IMPORTANT OPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THE LITERATURE ACCOMPANYING THE APPLIANCE.

CAUTION

LASER SAFETY

USE OF ANY CONTROLS, ADJUSTMENTS, OR PROCEDURES

TO PREVENT ELECTRIC SHOCK, MATCH WIDE BLADE OF

POUR EVITER LES CHOCS ELECTRIQUES, INTRODUIRE

Important Safety Instructions

- All the safety and operating instructions should be read before the appliance is operated.

- The safety and operating instructions should be retained for future reference.

- All warnings on the appliance and in the operating instructions should be adhered to.

- All operating and use instructions should be followed.

1. Water and Moisture - The appliance should not be

water - for example, near a bathtub, washbowl, kitchen sink,

used near

laundry tub, in a wet basement, or near a swimming pool, and the like.

PORTABLE CART

Figure 2

ceiling only as recommended by the manufacturer.

5. Ventilation - The appliance should be situated so location or position does not interfere with ventilation. For example, the appliance on a bed, sofa, rug, or similar surface that may block the ventilation openings; or, placed in a built-in installation, such as a bookcase or cabinet that may impede the flow

through the ventilation openings.

6. Heat - The appliance should be situated away from sources such as radiators, heat registers, appliances (including amplifiers) that

7. Power Sources - The appliance should be power supply only of the type described in the operating instructions or as marked on the appliance.

8. Grounding or Polarization - The precautions that taken so that the grounding or polarization means of an

appliance is not defeated.

9. Power - Cord Protection - Power-supply cords routed so that they are not likely to be by items placed upon or against them, paying particular attention to cords at plugs, convenience receptacles, and the point where they exit from the appliance.

10.Protective Attachment Plug - The appliance is equipped with an attachment plug having overload safety feature. See Instruction Manual for replacement or resetting of protective device. If replacement of the plug is required, be sure the service technician has used a replacement plug specified by the manufacturer that has the

same overload protection as the original plug.

11.Cleaning - The appliance should be cleaned only as recommended by the manufacturer.

12.Power Lines - An outdoor antenna should be located from power lines.

2. Carts and Stands - The appliance should be used only with a cart or stand that is recommended by th manufacturer.

3. An appliance and cart combination should be moved with care. Quick stops, excessive force, and uneven

surfaces may cause the appliance and cart combination to overturn.

4. Wall or Ceiling Mounting - The appli-

ance should be mounted to a wall or

that its

its proper

should not be situated

stoves, or other

produce heat.

connected to a

should be

walked on or pinched

protection. This is a

of air

heat

away

SAFETY PRECAUTIONS

13.Outdoor Antenna Grounding - If an outside antenna connected to the receiver be sure the antenna

system is

grounded so as to provide some protection against voltage surges and built-up static charges. Article 810 of the National Electrical Code, ANSI/NFPA 70, provides information with regard to proper grounding of the mast and supporting

structure, grounding of the lead-in wire to an antenna-dis charge unit, size of grounding conductors,location of antennadischarge unit, connection to grounding electrodes and requirements for the grounding electrode. See Figure 1.

EXAMPLE OF ANTENNA GROUNDING

GROUND CLAMP

ELECTRIC SERVICE EQUIPMENT

NEC - NATIONAL ELECTRICAL CODE

POWER SERVICE GROUNDING ELECTRODE SYSTEM (NEC ART 250 PART H)

ANTENNA LEAD IN WIRE

ANTENNA DISCHARGE UNIT (NEC SECTION 810-20)

GROUNDING CONDUCTORS (NEC SECTION 810-21)

GROUND CLAMPS

14.Non-use Periods - The power cord of the appliance should be unplugged from the outlet when left

unused for a long period

of time.

15.Object and Liquid Entry - Care should be taken so

that objects do not fall and liquids are not spilled into the enclosure through openings.

16.Damage Requiring Service - The appliance should

serviced by qualified service personnel when: a) The power-supply cord or the plug has been b) Objects have fallen, or liquid has been spilled

damaged; or

into the appliance; or c) The appliance has been exposed to rain; or

d) The appliance does not appear to operate

normally or exhibits a marked change in performance; or e) The appliance has been dropped, or the

enclosure

damaged.

17.Servicing - The user should not attempt to service the appliance beyond that described in the operating instructions.

All other servicing should be referred to qualified service personnel.

ADJUSTMENTS

1. TUNER SECTION

TEST EQUIPMENT

FM RF SSG

75 ohm Coaxal

FM Antenna

Terminal(75 ohm)

1. Signal Generator with a frequency range of FM broadcast.

2. Oscilloscope with a side amplifier of approximately 100 KHz.

3. FM 75/50Ω dummy antenna.

4. VTVM

Carrier Frequency : 98MHz Output Level : 26dBuV Modulation:Audio 1kHZ, 75kHz Deviation

SET

FM ALIGNMENT

1. Turn on the FM signal generator and the VTVM allowing 15 minutes warming-up period.

2. Connect the VTVM across the headphone jack or speaker terminal.

3. Set signal generator frequency as listed in ALIGNMENT CHART and maintain a sufficient output level to provide an indication on VTVM.

NOTE

1. Use a screwdriver with plastic or ceramic grip for all adjustments.

2. Standard test frequency 1 KHz and deviation 75 KHz for FM.

- FM RF, IF ALIGNMENT CHART -

Step Item Input Circuit Setup Output Circuit Setup Tuner Setting Adjust Point Adjustment

FM IF

Adjustment

Auto Stop Sensitivity

Connect stereo signal

generator to FM ANT

terminal (J001)

Connect stereo signal

generator to FM ANT

terminal (J001)

Connect DC voltme-

ter to edge R201

Connect DC voltme-

ter to edge of RV201

FM98MHz75KHz

Dev. 26dB

FM 98MHz

75KHz Dev.

26dB

L203

RV201

Adjust forDC 0V±0.1V

Adjust for DC

1.17V±0.02V

Confirm stereo indica-

tor is lighted and L/R

channel is separated.

Unless other specified set being switched FM mode, adjust generator's frequency to center of the FM band where no FM broadcast exists Otherwise adjustment of FM usable sensitivity, frequency range for FM band are not needed, but confirm these data are satisfied with specification. CAUTION : When realigning the FM receiving frequency the highest end of the frequency range should not be more than 108 MHz and the lowest end of the frequency range should not be less than 87.5 MHz, in order to comply with FTZ regulation in West Germany.

2. CD SECTION

Note:

1. Use the oscilloscope with more than 10M

2. Clean an object lens by an applicator with natural detergent when the signal level is lower than specified value

with the following checks.

RF LEVEL CHECK

1. Connect oscilloscope to test point TP502 and IC502 Pin66 on CD PCB.

2. Press power switch on.

3. Put test disc(TCD-781) in and press play button then pause button.

4. Confirm that oscilloscope waveform is clear. Clear RF signal waveform means that the shape"#"can be clearly distinguished at the center of waveform.

5. Adjust RV501 to get a clear waveform and maximum amplitude.

Ω

impedance.

RF Signal Waveform

VOLT/DIV : 200mV

TIME/DIV : 50ns

Level : 1.2+0.3Vp-p

E-F BALANCE ADJUSTMENT

Output Level

1. Connect oscilloscope to test point TP502 and TP503 on CD PCB.

2. Press power switch on.

3. Put test disc(TCD-781) in and press play button then pause button.

4. Pressing Fast Forward button, adjust RV502 to get that the oscilloscope waveform is symmetrical on the bottom in relation to 0V, and check this level. * Design and specifications may be subject to change without notice.

3. TAPE SECTION

ADJUSTMENTS

Traverse Waveform

Measurement

Input Level Measurement Point

Point

R-CH

L-CH

47 kohm

Input Point

VTVM

Test Tape be used

Tape Contents Use

MTT-111N 3 KHz Tape Speed Adjustment MTT-114N 10 KHz Head Azimuth Adjustment MTT-5511 Blank Record Frequency Property

HEAD ADJUSTMENT (AZIMUTH)

1. 10KHz test tape(example: MTT-114N) must be used for this adjustment.

2. Connect to VTVM or oscilloscope to the headphone jack or speaker terminal.

3. Press the play button.

4. Adjust the azimuth by using a screw driver to maintain the max. L&R output voltage.

5. Adjust tape A(1), tape B(2) respectively, Please secure the azimuth position by using locking paint.

Scope

RECORDING BIAS OSCILLATOR FREQUENCY ADJUSTMENT

1. Connect the frequency counter to TP603, GND.

2. Press the REC button.

3. Adjust L603 to obtain 80 KHz±100Hz

ADJUSTMENTS

Frequency Counter

Test Tape

TAPE ALIGNMENT CHART

Step Item Reference Value Test Tape Adjust Point Test Point Note FIG.

Normal

Tape Speed Adjustment

High 5,820~6,180Hz MTT-111N - - - - - -

2 Azimuth Adjustment

Recording Bias Oscilla-

tor Frequency Adjustment

3,015~3,025Hz MTT-111N RV601

3,000~3,010Hz MTT-111N RV601

Maximum Level Phase:Within90°

80 KHz±0.5

MTT-114N Head Screw

MTT-5511 L603

Line Out L/R Channel

Shorted TP601, TP602

Line Out L/R Channel

TP603,GND

Confirm Wow & Flutter is within 0.35%

FIG.1

Confirm Tape Speed of end position after adjustment at tape

FIG.1 start position Confirm High speed

after normal speed

FIG.1 adjustment

FIG.2,3,4 Adjust with frequency

counter connected. FIG.1

Test Tape : MTT-111N(3kHz)

MTT-5511(Blank)

Set

Output Level Measurement Point

FIG. 1 : Tape Speed & Record Bias Oscillator

Frequency Adjust Circuit

L-CH Peak

within

1 dB

R-CH

Screw Angle

Peak

Output Level

L-CH Peak

R-CH Peak

within

1 dB

Screw Angle

Adjust with Frequency

Counter Connected

Forward

Side

Reverse

Side

FIG. 2 : Tape Azimuth Adjust Location

(Record/Playback Head)

MTT-114N

(10kHz)

L-CH

Set

Screen Pattern

In Phase 45 90 135 180

Good Wrong

Oscilloscope

V H

Output Level Measurement Point

FIG. 3 : Tape Azimuth Adjust Head Screw & Waveform

FIG. 4 : Tape Azimuth Adjust Circuit & Waveform

EXPLODED VIEW AND PARTS LIST

AMI- 921DP / 921DPR

EXPLODED VIEW AND PARTS LIST

No. Parts Name PARTS Code Description Q'ty

9CD16148A0 ACRYL 1

1 WINDOW DOOR A/B

9CD16148B0 ACRYL 1 9CD18100A0 MIPS 1

2 DOOR COVER A/B

9CD18100B0 MIPS 1 9CD1809400 ABS 1

3 DOOR FRAME A/B

9CD1809500 ABS 1 4 SPRING DOOR EJECT L 9CD30080L0 STS 1 5 SPRING DOOR EJECT R 9CD30080R0 STS 1 6 CUSHION FOOT 9CD4207700 URETHAN FOAM RUBBER 2 7 KNOB VOLUME 9CD1337000 ABS 1 8 DAMPER ASSY 9CDM029800 2 9 LOCKER ASSY 9CDM029900 2

10 PLATE DECO 9CD0910200 PVC SHEET (T=1.0) 1 11 KNOB JOG DIAL 9CD1336800 ABS 1 12 BRKT SIDE 9CD2412900 ABS 2 13 PANEL FRONT 9CD0306700 MIPS 1 14 WINDOW FLT 9CD1614700 ACRYL 1

No. Parts Name PARTS Code Description Q'ty

35 HEAT SINK P 9CD4404200 AL T=2.0 1 36 COVER SIDE R 9CD0410000 MIPS 1 37 COVER BACK 9CD0409807 MIPS 1 S1 SCREW TAPTITE 7173261011 TT2 BIN 2.6X10 MFZN 19 S2 SCREW TAPTITE 7173300611 TT2 BIN 3X6 2 S3 SCREW TAPTITE 7173301011 TT2 BIN 3X10 MFZN 18 S4 SCREW TAPTITE 7173301012 TT2 BIN 3X10 BK 18 S5 SCREW TAPTITE 7173301212 TT2 BIN 3X12 BK 5 S6 SCREW TAPTITE 7173400611 TT2 BIN 4X6 6 S7 WASHER SCREW 9CD3102400 TT2 BIN 3X10+D14 5 P1 PCB CD 9CD6574800 197 X 123.5 X 1.6T 1 P2 PCB FRONT 9CD6577400 247 X 139 X 1.6T 1 P3 PCB MAIN 9CD6577600 319 X 197 X 1.6T 1 P4 PCB POWER 9CD6577900 197 X 115 X 1.6T 1 P5 PCB TAPE 9CD6577200 107 X 163 X 1.6T 1 P6 PCB OPTICAL JACK 9CD6577800 29 X 21.5 X 1.6T 1

15 KNOB EQ 9CD1336600 ABS 1 16 KNOB POWER 9CD1336900 ABS 1 17 KNOB FUNCTION 9CD1336700 ACRYL 1 18 PLATE FILTER 9CD0910300 LEXAN (T=0.125) 1 19 KNOB CONTROL 9CD1336500 ABS 1 20 KNOB DISC 9CD1337500 ABS 1 21 KNOB CD 9CD1336400 ABS 1 22 GUIDE FLT 9CD2506300 ABS 1 23 CASS DECK 9CD6007000 S/S ADR 2138MW 1 24 HOLDER PCB DECK 9CD2303600 MIPS 2 25 DOOR CD 9CD1810100 MIPS 1 26 HEAT SINK 9CD4402800 BSP T=0.5 1 27 CD MECHANISM 9CD6007100 CMS FR3 B TYPE 1 28 COVER TOP 9CD0409600 MIPS 1 29 COVER SIDE L 9CD0409900 MIPS 1 30 CHASSIS BOTTOM 9CD0607100 SECC 1 31 HEAT SINK DP2 9CD4405600 AL 4.0T 1 32 BRACKET HEAT SINK 9CD2414400 SUS T=0.3 1 33 HOLDER AC CODE 9CD2303300 ABS 1 34 BRACKET PCB A 9CD2413100 SECC T=1.0 1

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