Daewoo DV-K11WZ Service Manual

Service Manual

Model : DV-K11WZ-PB/A

DV-K11WY-PB

DV-K11WZ-QB/A

DAEWOO ELECTRONICS CO., LTD OVERSEAS SERVICE DEPT.

GENERAL

Power requirement	AC90~260V, 50/60Hz
Power consumption	Typical 13W
Temperature	5¡C~35£ ¡C£ (Operating)
	-20 C~60 C
	(Storage temperature)
Operating position	Horizontal only
Dimensions (WxHxD)	360x90x312 (mm)
Weight	Approx 5.4kg
Format	VHS standard
Tape widch	12.65mm
Tape speed	(SP): 23.39mm/sec
Maximum recording time
with full-size cassette	(SP): 240 min. with E-240
Maximum recording time	video cassette
with full-size cassette	(SP): 45 min. with E-45
	cassette

VIDEO

Signal system	PAL color and CCIR
	monochrome signals,
	625 lines/50 fields
Recording system	Rotary two-head helical scan
	with a slant double-azimuth
	combination video head
Input	1.0Vp-p, 75 ohms, unbalanced
Output	1.0Vp-p, 75 ohms, unbalanced
Simal to noise rallio	More than 43 dB (Rohde & Schwarz
	noise mater)
Horizontal resolution	More than 240 lines

AUDIO

Input	-8 dBs, (CENELEC standard)
	more than 47 k-ohms, unbalanced
Output	-6 dBs, (CENELEC standard),
	less than 1 k-ohm, unbalanced
	(10 k-ohms, load)
Frequency range	100 Hz to 8,000 Hz
	/20 Hz to 20 KHz (Hi-Fi)
Signal to noise ratio	38 dB (More than)
	/60dB (More than):Hi-Fi
Audio Distortion	Less than 3%(SP)
	/Less than 0.5%(SP):Hi-Fi
RF Output	UHF channel 36
	(Adjustable 30~39)

ACCESSORIES

Provided Accessories	Remote control unit
	RF Cable, Battery

•Design and specifications can be subjected to change without notice.

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

Confirm the specified insulation resistance or greater between power cord plug prongs and externally exposed parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.). See table below.

2.Dielectric strength test

Confirm specified dielectric strength or greater between power cord plug prongs and exposed accessible parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.) See table below.

		d
	3. Clearance distance	Primary circuit termimals
	When replacing primary circuit components, confirm specified
		d'
	clearance distance (d), (d') between soldered terminals, and
	between terminals and surrounding metalic parts. See table below.	Chassis
		a
		Fig. 1

Table 1: Rating for selected areas
	AC Line Voltage	Region	Insulation	Dielectric	Clearance
			Resistance	Strength	Distance (d), (d')
	100V	Japan	≥ 1 MΩ /500 V DC	1kV AC 1 minute	≥ 3 mm
	110 to 130V	USA &	– – –	900V AC 1 minute	≥ 3.2mm
		Canada
	* 110 to 130 V	Europe	≥ 4 MΩ /500 V DC	3 kV AC 1 minute	≥ 6 mm (d)
	200 to 240 V	Australia			≥ 8 mm (d')

* Class II model only.

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

4.Leakage current test

Confirm specified or lower leakage current between B (earth ground, power cord plug prongs) and externally exposed accessible parts (RF terminals, antenna terminals, video and audio

input and output terminals, microphone jacks, earphone jacks, etc.)

Measuring Method: (Power ON)					Exposed
					accessible			AC Voltmter
Insert load Z between B (earth ground, power cord plug prongs)					part	Z
								(high impedance)
and exposed accesible parts. Use and AC voltmeter to measure
across both terminals of load Z. See figure 2 and following table.						Earth Ground
						B power cord plug prongs
Table 2: Leakage current ratings for selected areas							Fig. 2
AC Line Voltage		Region		Load Z	Leakage Current (i)			Earth Ground
								(B) to:
100V		Japan			¡ ≤ 1m A rms			Exposed accessible
				1k				parts
110 to 130 V		USA &		1.5kµF	¡ ≤ 0.5 m A rms			Exposed accessible
				1.5k				parts
					¡ ≤ 0.7 m A peak			Antenna earth
110 to 130 V		Europe		2k	¡ ≤ 2 m A dc			terminals
200 to 240 V		Australia		50k	¡ ≤ 0.7 m A peak			Other terminals

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

INFORMATION

Z-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB

V-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11

Z-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB

V-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11

Z-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB

V-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11

Z-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB

V-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11WY-PB DV-K11WZ-QB/A DV-K11WZ-PB/A DV-K11

VIDEO CASSETTE RECORDER

1. CONTROLS AND FUNCTIONS ...................................................................................................	2
2. ELECTRICAL ADJUSTMENTS
2-1. SERVO CIRCUIT ADJUSTMENT METHOD .......................................................................................	3
2-2. AUDIO CIRCUIT ADJUSTMENT METHOD ........................................................................................	4
3. TROUBLE SHOOTING FLOW CHART
3-1. POWER CIRCUIT .................................................................................................................................	5
3-2. SERVO-SYSCON CIRCUIT .................................................................................................................	7
3-3. AUDIO CIRCUIT (NORMAL) ..............................................................................................................	12
3-4. AUDIO CIRCUIT (HI-FI) ......................................................................................................................	14
3-5. VIDIO CIRCUIT ..................................................................................................................................	16
4. WAVEFORMS ON VIDEO CIRCUIT........................................................................................	22
5. µ-COM PART .......................................................................................................................................	25
6. CIRCUIT DIAGRAM..........................................................................................................................	27
6-1. CONNECTION DIAGRAM .................................................................................................................	27
6-2. POWER CIRCUIT DIAGRAM.............................................................................................................	28
6-3. SERVO/SYSCON CIRCUIT DIAGRAM.............................................................................................	29
6-4. VIDEO & HEAD-AMP CIRCUIT DIAGRAM .......................................................................................	30
6-5. AUDIO CIRCUIT DIAGRAM...............................................................................................................	31
6-6. HI-FI AUDIO CIRCUIT DIAGRAM......................................................................................................	32
6-7. KARAOKE CIRCUIT DIAGRAM.........................................................................................................	33
6-8. LOGIC SW CIRCUIT ..........................................................................................................................	34
7. COMPONENTS LOCATION GUIDE ON PCB BOTTOM VIEW.................................	35
8. DISASSEMBLY
8-1. PACKING ASSEMBLY.......................................................................................................................	37
8-2. SET ASSEMBLY.................................................................................................................................	38
8-3. PAN ASSEMBLY................................................................................................................................	39
9. ELECTRICAL PARTS LIST............................................................................................................	40

1. CONTROL AND FUNCTIONS

FRONT

DV-K11WZ-PB/A

					DIGITAL ECHO	VOL 1	VOL 2
POWER STOP/EJECT		NTSC PLAY BACK RECORDING • HIGH SPEED REWIND
				#
					AUTO REPEAT	MIC 1	MIC 2
PAUSE/STILL
	REW	PLAY	FF	CST.IN NTSC A.REPEAT REC
PLAY				DV-K11W	REC
	L	Hi-Fi	R

DV-K11WY-PB (Hi-Fi)

					DIGITAL ECHO	VOL 1	VOL 2
POWER STOP/EJECT		NTSC PLAY BACK RECORDING • HIGH SPEED REWIND
				#
					AUTO REPEAT	MIC 1	MIC 2
PAUSE/STILL
	REW	PLAY	FF	CST.IN NTSC A.REPEAT REC
PLAY				DV-K11W	REC

DV-K11WZ-QB/A (NORMAL)

REAR

	RF OUT	AUDIO
	VIDEO
	L	R
	CH.R CH.L	IN
	ANT. IN
	TEST
	ON	OUT
	OFF

RF OUT

		VIDEO AUDIO
CH.R CH.L		IN
	ANT. IN
TEST
ON		OUT
OFF

2

2. ELECTRICAL ADJUSTMENT

SERVO CIRCUIT ADJUSTMENT METHOD

	VIDEO HEAD SWITCHING	POSITION
	Adjustment Parts	Checking Point	Measuring Equipment	Mode	Test Tape
	R595	R305	Oscilloscope	PLAY	DP-2
		PT01 PIN ¤Ø			(STAIR STEP)

		PHONE	MODULATOR
	R305	JACK
			POWER
	6.5H±0.5H		MODULE
	PT01 R595
			TOP VIEW
	CH-1
	OSCILLOSCOPE
	CH-2

!Connection Method

@Adjustment Procedure

1.Play back the test tape.(STAIR STEP DP-2)

2.Set the oscilloscope in the chop mode. Connect CH1 to the SW pulse(PT01 PIN#), and CH2 to the VIDEO OUT(R305 ) and trigger the scope with signal from CH1.

3.Adjust R595 to the positive rising edge of SW PULSE at 6.5H±0.5H from the V-SYNC.

CH1		SW 30Hz
		(PT01	3	PIN)
		VERTICAL SYNC
CH2
	1H	(R305)
		0.5H
		6.5H ± 0.5H
	TRIGGER

3

AUDIO CIRCUIT ADJUSTMENT METHOD

AUDIO RECORD BIAS		Checking Point		Measuring Equipment		Test Tape		Input Signal
Adjustment Parts
R292		A/C Head PCB		Audio level meter		Rec		None signal
		R01

3.0mVrms

	PHONE	MODULATOR
	JACK
		R292
		DECK ASSY
		A/C HEAD

!Connection Method

@Adjustment Procedure

1.Set the power on mode.

2.Set the input to open mode

3.Connect the Audio level meter to R01

4.After inserting a blank tape, record in SP mode.

5.Adjust R292 to obtain 3.0 mVrms.

Audio LEVEL METER

+

–

POWER

MODULE A/CHEAD

R01

4

3. TROUBLE SHOOTING FLOW CHART

POWER CIRCUIT

•When change the parts which are out of order, first, remove the power plug from the socket and then discharge the voltage across between both terminals of C807. (Use an external scores of KΩ resistance)

•When check the primary circuit by using the oscilloscopes insulate the oscilloscope surely. (Use the isulating transformer) and must connect GND into the primary GND), (But there is no connection when check the secondary circuit).

•When change SM801(POWER MODULE), check FUSE and Cement resistance surely.

NO output Voltage

YES

Prepare the instrument connecting the insulating trans.

YES

Check F801 FUSE

YES

Is voltage applied to D801?

YES

Is voltage applied to the both terminals of C807?

NO

Check D801, L801

NO

Check R802

YES

Check power module

5

No Voltage

output

NO

Is voltage supplied

Check F801, L801,

Via CN11?

D802

YES

YES

The voltage of #1 of

Check the secondary

IC11 is 5.7V and stable

circuit

NO

NO

The voltage of #1 of IC11

fluctuate

in 4.8V~5.7V

YES

Measure resistance

Terminal open and

between GND of CN21

measure the output

and each terminal

Voltage

of CN21

Resistance >> 100Ω

The 12DC of each

NO

Change T11

wire of T11 is ok

YES

NO

Change parts

Primary parts is ok

out of order

YES

NO

Change parts

Secondary parts ok

out of order

Check the pattern and T11, L11, IC11

	The voltage					NO			Check the
									parts outside
	is ok
									module
			YES
	Check the Diode,
	Condenser inside
	Module

6

SERVO SYSCON CIRCUIT

A

Playback picture is not good.

Noise appears						NO			Adjust
although adjusting
tracking.									tracking
		YES							Noise appears
Noise shakes up						NO
and down on the									although change
screen.									cassette tape.
		YES
Is CTL pulse out						NO			CTL HEAD height is
from pin 20of IC601.									normal and there is
									not dust.
		YES									YES
Is CTL pulse input						NO			Check C503, C504,
to pin 7 IC501
									C506
		YES

YES	Check and
	re-adjust the
	Path of Deck.

NO	Adjust the HEAD
	height and remove
	dust

Check circuit adjacent to IC601

The voltage of pin	NO
58 of IC601 is not	check R539, C518
changed.
YES
Check IC601

7

B

Playback picture

is not good.

YES

Noise appears

NO

Check flow A

on the screen

on the whole.

YES

Are SW pulse

NO

Is SW pulse supplied

NO

Check D.PG input

applied to

from pin 23 of IC601?

and connector.

HeadAmp circuit?

YES

YES

Is Enve.wavefrom

Check pattern

supplied to at pin 4 of

PT01

YES

NO

Check video circuit.

Check connector, Head

Change head

Amp and Head dust.

		C
	Auto stop during
	playback
	YES
	Is Reel pulse	NO
	applied to pin 7 and
		Check reel sensor.
	14 of IC601?
	YES

Is D.FG applied to	NO	Check connector
pin 17 of IC601		D.FG circuits.
YES
Check IC601

8

Drum M/T loading stops.

Is Motor 12V supplied?

YES

Is pin 17 D.FG of

IC601 supplied.

YES

Is pin D.PWM (pin 30 ) of IC601 supplied?

YES

Check connector and Motor.

D

NO	Check
	POWER MODULE

NO

Check C509, R523

NO

Check IC601

Capstan M/T loading stops.

YES

Is Motor 12V supplied?

YES

Is the input of pin 6 of PJ502 2V-3.5V?

YES

Is pin 4 of PJ502 2.5V

YES

Is pin 31 (C.PWM) of IC601 Supplied?

YES

Check connector and Motor

E

NO

Check power circuit.

NO	Check circuit of R515,
	R516, R517.

NO

Check R541, R542

NO

Check IC601

9

Drum M/T and Capstan M/T rotate at regular speed. (In REC mode)

NO
Is C. Sync applied to	NO
pin 8 of IC601?
YES
Check Motor.

F

Check C. Sync of

IC 401 and Pattern

G

Emergency mode when plugging (Power cord)

Is EVER 5V supplied?	NO	Check power circuit.
YES
Does X601 crystal osciliate?	NO	Check IC601 and X601.
YES
Is CAM SW DATA Correct?	NO	Recheck connector
		and CAM SW contact.
YES

Check IC502.

YES

Check IC 601.

10

H

Cassette is not inserted.

					NO
Is Motor 12V supplied?
		YES			NO
CAM DATA is changed
when CST IN?
		YES			NO
Is 5V applied to
pin 4 of IC502 when CST IN?
		YES
Chek IC502

Check power circuit

Check connector.	NO	Check DECK part.

	Is 5V supplied at	NO
		Check PATTERN
	pin 37 of IC601?
	YES
	Check IC601

11

AUDIO CIRCUIT (NORMAL)

No sound in the playback mode.

Is the output at pin‘

NO

Is 9V applied to pin &

of IC201?

of IC201?

YES

Is 5V applied to

1of IC201?

YES

Is pin=of IC201 0V?

YES

Is there Audio output at pin 10 of IC201?

YES

Is pin # of IC201

GND?

YES

Check PJ504

and HEAD.

NO

Check power circuit.

NO

Check IC 601

NO

NO	Check circuit adjacent
	to R211, R212

NO

Check IC201

12

No sound in the playback mode after recording

Is the signal applied to	NO
pin 6 of IC201?

										NO
Is 5V applied to
pin = of IC201?
		YES								NO
Is there output at pin “
of IC201?
		YES

NO

Does T201 oscillate?

YES

Check circuit adjacent R209, R210, C207

Check IC601.

Check IC201.

Is the voltage above 10V at pin # of T201?

Check Q201 collector:above 10V Base: 0V

Check T201

Is record current	NO	Asjust Record current.
3.0mVrms?
YES
Is pin 1 of IC201 0V?	NO	Check IC201.
YES
Clean HEAD.

NO	Check Q202 and T201.
NO	Check Q201.

13