Daewoo DVR-1983D, DVR-1989D, DVR-1181D Service Manual

Service Manual

Model : DVR-1989D

DVR-1989D(KD) DVR-1989D(BB) DVR-1989D(GB) DVR-1983D DVR-1983D(KD) DVR-1983D(BB) DVR-1983D(GB) DVR-1181D DVR-1181D(KD) DVR-1181D(BB) DVR-1181D(GB)

D AEW OO ELECTRONICS CO., LTD.

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Safety Check after Servicing

Examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify compliance with safety standards.

1. Insulation resistance test

1. Confirm the specified insulation resistance or greater between power cord plug prongs and e xternally e xposed parts of the 1.

1. set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.). 1.

1. See table below.

2. Dielectric strength test

1. Confirm specified dielectric strength or greater between power cord plug prongs and e xposed accessib le parts of the set

1. (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.). See

1. table belo w.

3. Clearance distance

1. When replacing primary circuit components, confirm specified 1. 1. 1.

1. clearance distance (d), (d') betw een soldered terminals, and between

1. terminals and surrounding metalic parts. See table below.

T able 1: Rating for selected areas

*Class ¥–model only.

Note: This table is unofficial and for reference only. Be sure to confirm the precise v alues for your particular country and locality .

4. Leakage current test

1.Confirm specified or lower leakage current between B (earth ground, power cord plug prongs) and externally exposed 1. 1. 1.

1. accessible.parts (RF terminals, antenna terminals, video and audo input and output terminals, microphone jacks, earphone

1. jacks etc.)

1. Measuring Method: (Pow er ON)

1. Insert load Z between B (earth ground, power cord plug prongs) and

1. exposed accessible parts. Use and AC voltmeter to measure across

1. both terminals of load Z.

1. See figure and following tab le .

T able 2: Leaka ge current ratings f or selected areas

Note : This table unofficial and for reference only. Be sure to confirm the precise values for your particular country

Note : and locality.

AC Line Voltage Region Insulation dielectric Clearance

Resistance Strengthe Distance (d), (d')

100V Japan 1M/500 V DC 1kV 1 minute ¡ˆ3 mm

110 to 130V USA & --- 900 V 1 minute ¡ˆ 3.2 mm

Canada

* 110 to 130 V Europe 10 M/500 V DC 4kV 1 minute ¡ˆ6 mm (d)

200 to 240 V Australia ¡ˆ‘ mm (d')

Primary circuit terminals

Fig.8

AC voltage (high impedance)

AC Line Voltage Region Load Z Leakage Curent (i) Earth Ground

(B) to:

100V Japan i ¡´1mA rms Exposed accessible

parts

110 to 130 V USA & i ¡´0.5 mA rms Exposed accessible

Canada parts

110 to 130 V Europe i ¡´0.7 mApeak antenna earth 200 to 240 V Australia i ¡´2 mAdc terminals

i ¡´0.7 mApeak Other terminals

i ¡´ 2 mAdc Other terminals

1K ¥

1.5K ¥

1.5k¥

SECTION 1. GENERAL

1111-1. IDENTIFICATION AND OPERATION OF CONTROLS 2

SECTION 2. ELECTRICAL ADJUSTMENT

1112-1. ALIGNMENT AND ELECTRICAL ADJUSTMENTS 5 1112-2. SERVO-LOGIC CIRCUIT ADJUSTMENT METHOD 6 1112-3. VIDEO CIRCUIT ADJUSTMENT METHOD 6

1112.4. AUDIO CIRCUIT ADJUSTMENT METHOD 10

SECTION 3. CIRCUIT DIAGRAM

1113-1. CONNECTION DIAGRAM 11 1113-2. POWER CIRCUIT 12 1113-3. SERVO/SYSCON CIRCUIT 13 1113-4. VIDEO CIRCUIT 14 1113-5. PRE-AMP CIRCUIT 15 1113-6. AUDIO CIRCUIT 16 11 3-7. LOGIC SW CIRCUIT (D VR-1181 SERIES) 17 11 3-8. LOGIC SW CIRCUIT (D VR-1383 SERIES) 18 11 3-9. LOGIC SW CIRCUIT (D VR-1989 SERIES) 19

SECTION 4. EXPLODED VIEWS AND PARTS LIST

1114-1. PACKING ASSEMBLY 20 1114-2. SET ASSEMBLY 21 1114-3. PANEL FRONT ASSEMBLY (DVR-1181 SERIES) 22 1114-4. PANEL FRONT ASSEMBLY (DVR-1383 SERIES) 23 1114-5. PANEL FRONT ASSEMBLY (DVR-1989 SERIES) 24

1114-6. MAIN CHASSIS ASSEMBLY 25

SECTION 5. COMPONENTS LOCATION GUIDE ON PCB (T OP VIEW)

1115-1. MAIN PCB AS 26 1115-2. FRONT PCB AS 27 1115-3. POWER PCB AS 28

SECTION 6. ELECTRICAL PARTS LIST

1116-1. STANDARD PART NUMBER CODING 29

SECTION 7. ELECTRICAL PARTS LIST

1117-1. ELECTRICAL PARTS LIST BY ASSEMBLIES 33

TABLE OF CONTENTS

SECTION 1.

GENERAL

1.1 IDENTIFICATION AND OPERATION OF CONTR OLS

DVR-1181 SERIES

DVR-1383 SERIES

DVR-1989 SERIES

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POWER Switch & LAMP

Turns VCR power on and off .

¤ŁSTOP/EJECT Button

In STOP mode this button makes a cassette come out of compartment. In any other mode except STOP this button operates STOP function.

¤ØCassette Compartment

When the cassette is inserted in this compar tment, the cassette will automatically be ready for operation.

¤ŒPLAY Button

Push to playback the recorded tape .

¤ºREW Button

The REW Button serves a dual purpose. Press this button to rewind the tape. When this button is pressed during the playback mode, the picture will move quickly backward as three times of playback speed. When this button is pressed again, the picture will move quickly backward as nine times of playback speed and you can search for the desired part of program. When play button is pressed, the recorder will return to the play back mode.

¤ FF Button

The FF Button serves a dual purpose. Push to fast forward the tape. When this button is pressed during the playback mode, the picture will move quickly forward as three times of playback speed. In this mode, when this button in pressed again, the picture will move quickly forward as nine times of playback speed and you can search for the desired part of program. When play button is pressed, the recorder will return to the playback mode.

¤ PA USE/STILL Button

In the recording mode, you can stop the operation of the recorder temporarily. In the playback mode, a picture will apear in the STILL mode. The STILL mode is released automatically after 5 minutes, and will return to the PLAY mode.

¤ RECORD Button

Push this button to record. If the safety tab has been removed from the cassette, it will not be possible to record, thereby preventing your recordings from accidentally erased.

¤ ¤ TRACKING + /

Buttons

Press one of the buttons to eliminate noise bars or black streaks across the picture during playback.

¤æREMOTE Sensor

Receives signals from the Remote Controller.

¤ AUT O REPEAT Button

Press this button and the recorder will automatically rewind the tape at the end of the signal and repeat the playback continuously until the auto repeat button is pressed again.

¤ TV/VCR Button

Press this button to select the TV or VTR mode.

¤ CASS-IN indicator lamp

Illuminates when a cassette tape is loaded.

¤ıREC lamp

Illuminates when REC button is pressed.

§ VCR lamp

Illuminates when VCR mode.

§æ AUT O REPEAT lamp

Illuminates when AUTO REPEAT button is pressed.

§ REW lamp

Illuminates when REW button is pressed.

§ PLAY lamp

Illuminates when the play, still, auto repeat button is pressed.

§ F.F lamp

Illuminates when FF button is pressed.

§ıPAL lamp

This lamp is lit up in PAL MODE.

N.B : When this button is pressed, all other control keys

are inoperable until AUTO REPEAT is pressed again

§ ANT IN Terminal

Connect a TV aerial to this terminal.

§ RF OUTPUT Terminal

Connect to the aerial terminal of a TV receiver with the RF Cable (provided.)

§łTEST SIGNAL SWITCH

In test signal mode, you can check channel accordance of the TV and VCR.

§øRF OUTPUT CHANNEL ADJUSTMENT SCREW

In video playback mode, you can adjust more accurately the RF OUTPUT for obtaining clean picture.

§œAUDIO IN SOCKET (PHONO)

§ßVIDEO IN SOCKET (PHONO)

§ AUDIO OUT SOCKET (PHONO)

§ VIDEO OUT SOCKET (PHONO)

§ DC JACK

Connect this Jack to DC Source (DC 12V)

POWER CORD

Connect this cord into the AC outlet.

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§ §ø § § §

For these adjustment, use the equipment mentioned below and proceed by using the alignment tape and video signal.

Instrument and T ools Required

1. Color TV receiver .

2. Oscilloscope having 10 MHz or more bandwidth.

3. Color-bar generator.

4. Frequency counter.

5. VTVM.

6. VOM (20 Kµ/V).

7. Audio oscillator .

8. Audio attenuator.

Signal Level and Input and Output Impedance Requirement

1. Video input: Negative sync., 1Vp-p standard composite

1. video signal, 75Ω.

2. Video output: Same as above.

3. Audio input: Line - 10dBs, 47KΩ.

4. Audio output: -5dBs, 10KΩor less.

Adjustment Sequence

The VCR should be adjusted in the sequence shown below.

The suitable output waveform of the color-bar signal generator is shown below.

SECTION 2.

ELECTRICAL ADJUSTMENTS

2-1. ALIGNMENT AND ELECTRICAL ADJUSTMENT

2-2. SERVO-LOGIC CIRCUIT ADJUSTMENT METHOD

1. VIDEO HEAD SWITCHING POSITION

1) Play back the test tape .

2) Set the oscilloscope in the CHOP mode connect the CH1 to SW pulse PT01 2 PIN the CH2 to TP396 with CH1 triggering.

3) Adjust RV501 for the positive trigger until 6.5H¡ 0.5H cycles before the vertical SYNC pulse.

2-3. VIDEO CIRCUIT ADJUSTMENT METHOD

1. E E VIDEO LEVEL

1) Feed the color bar signal to the line input terminal. And set for the stop (EE) mode.

2) Connect the oscilloscope to TP395 and trigger the scope with a composite SYNC signal at TP313 .(COMP.SYNC.)

3) Adjust the oscilloscope so that it can display a wa veform of approx. 2H.

4) Adjust RV395 to obtain 0.5¡ 0.02 Vp-p between SYNC TIP and 100% white le v el.

Adj. Location Chec king Point Measuring Equipment Mode Test T ape

RV501

PT01 3 PIN

Oscilloscope Play DP-1

TP396

Adj. Location Chec king Point Measuring Equipment Mode Test T ape

RV395 TP395 Oscilloscope EE ƒ¡

0.5¡ 0.02Vp-p

2. PLAYBACK Y-SINGAL OUTPUT LEVEL

1) Playback the test tape (Color Bar Signal).

2) Connect the oscilloscope to TP396 and trigger the scope will a composite SYNC signal at TP313.

1) Adjust the scope so that it can display a wa v eform of approx. 2H.

3) Adjust RV396 to optain 2.0VP¡ 0.2 Vp-p between the SYNC TIP and 100% white le v el.

3. SYNC TIP FREQUENCY

1) Set the unit to stop mode without video signal. (Jack of video line input is shorted with ground).

2) Conncet the frequency counter to TP391.

3) Adjust RV391 until the SYNC TIP frequency becomes 3.80 MHz ¡ 0.1 MHz.

Adj. Location Chec king Point Measuring Equipment Mode Test T ape

RV396 TP396 Oscilloscope PB DP-1

Adj. Location Chec king Point Measuring Equipment Mode Test T ape

RV391 TP391 Oscilloscope REC. ƒ¡

2.0¡ 0.2Vp-p

Horizontal 10¥ s/div V ertical 0.5V/div.

4. LUMINANCE AND COLOR RECORD CURRENT

1) Input Color bar signal in 'video line in'.

2) Make every adjustment in REC mode.

3) Connect CH. 1 of oscilloscope to TP399 and TP GND and CH. 2 TP313 (C.SYNC), and then trigger the scope with an external signal.

4) Adjust RV491 Until the color record current level (RED REFERENCE) becomes 100¡ 5mVp-p.

5) Connect CH. 1 of oscilloscope to TP399 and TP GND and CH. 2 TP313 (C.SYNC), and then trigger the scope with an external signal.

6) Adjust RV399 Until the Luminance level becomes 300¡ 10mVp-p.

Adj. Location Chec king Point Measuring Equipment Mode Test T ape

RV339

TP399 Oscilloscope REC. Blank T ape

TV491

Color Record Current a:100mVp-p¡ 5mVp-p

Y Record Current b:300mVp-p¡ 10mVp-p

5. FM DEVIATION

1) Confirm that the adjustment for the playbac k Y-Signal output lev el has been made corretly.

2) Feed the color bar signal to the line terminal, and set the VCR to the record mode.

3) Connect the oscilloscope to TP396 and trigger the scope with a composite sync signal (TP313).

4) Record the color bar signal for a f e w min ute and pla ybac k it. Then confirm that the pla ybac k Y-signal output lev el is

4) 2.0¡ 0.2 Vp-p.

5) If the playback y signal output level is not 2.0 ¡ 0.2 Vp-p, the adjust as f ollo ws . 5-1) Set the VCR in the record mode. 5-2) Turn the variable RV392 a little. 5-3) Record the color bar signal f or a f e w min ute and pla ybac k it. 5-4) Confirm the playback Y signal output is 2.0 ¡ 0.2Vp-p. 5-5) Repeat from step until the playbac k Y-signal output lev el becomes 2.0¡ 0.2Vp-p between the sync. TIP and 100% white

level.

Adj. Location Chec king Point Measuring Equipment Mode Test T ape

RV332 TP399 Oscilloscope REC.

DP-1 Color Bar

Blank Tape

2.0¡ 0.2Vp-p

Horizontal 10¥ s/div V ertical 0.5V/div.

2-4. AUDIO CIRCUIT ADJUSTMENT METHOD

1. PLAYBACK OUTPUT LEVEL

1) Connect the audio level meter to the audio line output jack.

2) Play back the test tape .

3) Adjust RV291 until the audio level meter reads -5¡ 1.5dBs play back output.

2. PLAYBACK OUTPUT FREQUENCY CHARA CTERISTIC

1) Playback the Test tape, and confirm that the playback output le v el at 7 KHz is within 0 ¡ 3 dB as referenced to the 1 KHz 1) 1)

playback output le vel.

3. BIAS CURRENT ADJUSTMENT AND OSCILLATION FREQUENCY CHECKING

1) Supply the signal in the OPEN mode

2) Conncet the positive lead of the VTVM to TP201 and negativ e lead to TP202.

3) Set the VCR in recording mode.

4) Confirm the frequency counter display is 70 KHz¡ 10% and adjust RV292 until VTVM reads 2.3 mVrms

4. RECORD-PLAYBACK FREQUENCY RESPONSE

1) Connect the audio signal generator to the audio line input jack, and the audio level meter to the audio line output jac k

2) Record referene audio signal of the 400 Hz and 10 KHz (SP) audio signal at -20 dBs .

3) Check to insure that 10 KHz playbc k output level is within -1¡ 3 dB as referenced to the 400 Hz pla ybac k output level.(SP)

4) If the difference between 10 KHz and 400 Hz playback output le v el is more than +1 dB , increase the bias current more than

4) 2.3mVms, and if the difference is less than -3 dB , reduce the bias current less than 2.3 mVrms .

5. RECORD-PLAYBACK OUTPUT LEVEL

1) Connect the audio signal generator to the audio line input jack.

2) Record and playback the input of the audio reference signal 1 KHz, -10 dBs.

3) Confirm that play output lev el is -5¡ 3dBs as ref erenced to the pla ybac k output level

Adj. Location Measuring Point Measuring Equipment Condition of Adj. Test Tape

Checking Audio Line Out A udio Le v el Meter PLAY Mode

1KHz, 0dBm 6KHz, 0dBm

Adj. Location Measuring Point Measuring Equipment Condition of Adj. Test Tape

RV291 Audio Line Out A udio Le v el Meter PLAY Mode DN-1

Adj. Location Measuring Point Measuring Equipment Condition of Adj. Test Tape

Checking Audio Line Out

Audio Lev el Meter

REC. Play Blank Tape

Audio Signal Generator

Adj. Location Measuring Point Measuring Equipment Condition of Adj. Test Tape

Checking Audio Line Out

Audio Lev el Meter

REC. Play Blank Tape

Audio Signal Generator

Adj. Location Measuring Point Measuring Equipment Condition of Adj. Test Tape

RV292 TP201, TP202 Frequency Counter REC. Mode Blank T ape

3-1. CONNECTION DIAGRAM

SECTION 3.

CIRCUIT DIA GRAM

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