Daewoo DV-F882DY-CK, DV-F802DY-CK Schematic

Service Manual

MODEL : DV-F882DY-C

DV-F882DY-A

DV-F882DY-C

DV-F882DY-A

DV-F882DY-M

DV-F882PY-D

DV-F802D-CP

DV-F802D-AP

DV-F802P-DP

DAEWOO ELECTRONICS CO., LTD.

SPECIFICATIONS

SYSTEM

Video signal	PAL standard colour
	PAL/SECAM
channel memory	55 positions
UHF output signal	30-39 CH (adjustable)
	73±3dBuV

VIDEO

Input: Video Line in	1.0Vp-p
	75 ohms unbalanced, sync.
	negative
Output: Video line out	75 ohms unbalanced, sync.
	negative
Signal to noise ratio	More than 43dB (SP)
Horizontal resolution	230 lines

AUDIO

Input: Audio Line in	Impedance: more than
	50Kohm
	–8 dBm, unbalanced
Output: Audio line out	Impedance: less than 1Kohm
	–6 dBm, unbalanced

Channel coverage

Frequency response	100 Hz-8KHz
	Hi-Fi, 20Hz-20kHz
Signal to noise ratio	More than 38 dB
	Hi-Fi More than 60dB
Audio Distortion	Less than 3% (SP)
	Hi-Fi Less than 0.5%

TAPE TRANSPORT

Tape width	12.65mm (1/2")
Tape speed	23.39mm/sec
Maximum recording time	360 min, with E-180 tape (LP)
FF. REW time	Approx 4 min (E-180)

GENERAL

Power requirements	AC 230V 50Hz
Power consumption	19W
	Nicam 20W

DIMENSIONS

Set size (WxHxD)	360x90x312 mm
Carton size (WxHxD)	445x180x412 mm
Weight (gross)	5.4Kg

SYSTEM PAL,SECAM-B/G

PAL,SECAM-B/G,D/K PAL-I

HYPER BAND

VHF Ch 2~12

UHF Ch 21~69

Channel CATV Ch X,Y,Z UHF Ch 21~69

SI~S41

IN/OUTPUT JACK TYPE

	Model	EUROPE
	JACK	SCART Type
	TYPE

• 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.

3.Clearance distance

When replacing primary circuit components, confirm specified clearance distance (d), (d') between soldered terminals, and between terminals and surrounding metalic parts. See table below.

d

Primary circuit termimals

d'

Chassis

a

Table 1: Rating for selected areas				Fig. 1
	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')
					(a: Power cord)

* 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
	Insert load Z between B (earth ground, power cord plug								AC Voltmter
							part	Z
	prongs) and exposed accesible parts. Use and AC								(high impedance)
	voltmeter to measure across both terminals of load Z.							Earth Ground
	See figure 2 and following table.
								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				¡ ≤ 0.7 m A peak		Other terminals
					50k			¡ ≤ 2 m A dc

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

TABLE OF CONTENTS

SECTION 1. CONTROLS AND FUNCTIONS..........................................................................................................	2
SECTION 2. ELECTRICAL ADJUSTMENTS
2-1. SERVO CIRCUIT ADJUSTMENT METHOD .....................................................................................................................	3
2-2. AUDIO CIRCUIT ADJUSTMENT METHOD......................................................................................................................	4
2-3. IF MODULE CIRCUIT ADJUSTMENT METHOD..............................................................................................................	5
SECTION 3. TROUBLE SHOOTING FLOW CHART
3-1. POWER CIRCUIT.............................................................................................................................................................	16
3-2. LOGIC CIRCUIT...............................................................................................................................................................	18
3-3. SERVO-SYSCON CIRCUIT.............................................................................................................................................	20
3-4. AUDIO CIRCUIRT (NORMAL) .........................................................................................................................................	25
3-5. AUDIO CIRCUIT (HI-FI)....................................................................................................................................................	27
3-6. VIDEO CIRCUIT ...............................................................................................................................................................	29
SECTION 4. CIRCUIT DIAGRAM
4-1. CONNECTION DIAGRAM (DV-F802 SERIES)................................................................................................................	39
4-2. CONNECTION DIAGRAM (DV-F882 SERIES)................................................................................................................	40
4-3. POWER CIRCUIT.............................................................................................................................................................	41
4-4. SERVO-LOGIC CIRCUIT.................................................................................................................................................	42
4-5. LOGIC CIRCUIT (DV-F802 SERIES) ...............................................................................................................................	43
4-6. LOGIC CIRCUIT II (DV-F882 SERIES) ............................................................................................................................	44
4-7. HEADAMP CIRCUIT ........................................................................................................................................................	45
4-8. VIDEO CIRCUIT ...............................................................................................................................................................	46
4-9. HI-FI AUDIO CIRCUIT......................................................................................................................................................	47
4-10. PIF NICAM CIRCUIT......................................................................................................................................................	48
4-11. PIF/MPX CIRCUIT..........................................................................................................................................................	49
4-12. PIF CIRCUIT...................................................................................................................................................................	50
4-13. OSD CIRCUIT ................................................................................................................................................................	51
4-14. VPS/PDC CIRCUIT ........................................................................................................................................................	52
4-15. IN/OUT SW CIRCUIT I...................................................................................................................................................	53
4-16. IN/OUT SW CIRCUIT II..................................................................................................................................................	54
4-17.REMOCON CIRCUIT......................................................................................................................................................	55
SECTION 5. VOLTAGE CHARTS.................................................................................................................................	56
SECTION 6. COMPONENTS LOCATION GUIDE ON PCB BOTTOM VIEW........................................	64
SECTION 7. DIS ASSEMBLY ........................................................................................................................................	69
SECTION 8. ELECTRICAL PARTS LIST..................................................................................................................	73

1

SECTION 1. CONTROLS AND FUNCTIONS

FRONT

DV-F882 Series

=

PLAY

POWER

REW

FF

EJECT	STOP
	REC/OTR

=

		B . L . U . E D . I . A . M . O . N . D
POWER		RAPID REWIND SYSTEM
EJECT	VIDEO	L –AUDIO– R

CHANNEL

PLAY

REW

FF

STOP

REC/OTR

DV-F802 Series

PLAY

REW F.F

POWER EJECT

STOP

REC/OTR

õ CH.TRK.ö

REAR
		RF OUT
TV	CH.H	CH.L
		ANT. IN
	TEST
EURO-AV		ON
		OFF
2

SECTION 2. ELECTRICAL ADJUSTMENT

2-1. SERVO CIRCUIT ADJUSTMENT METHOD

1. PLAYBACK PHASE

	Adjustment Parts	Checking Point	Measuring Equipment	Mode	Test Tape
	Check	JPT01	Oscilloscope	Play	DP-2
		PT01 PIN ¤Ø
	• Connection Method

Modulator

JPT01

6 PATH JIG

PT01

TOP VIEW

CH-1

OSCILLOSCOPE

CH-2

• Adjustment Procedure

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

2)Set the oscilloscope to the CHOP mode. Connect CH1 to the SW PULSE (PT01 PIN ¤Ø).

3)Insert PATH JIG and Press “REC” button on the remote controller.

4)Check the position of the V-sync from the rising edge of the SW pulse. (Standard: 6.5H±0.5H)

3

2-2. AUDIO CIRCUIT ADJUSTMENT METHOD

1. AUDIO RECORD BIAS

	Adjustment Parts	Checking Point	Measuring Equipment	Test Tape	Input Signal
	R290	A/C Head PCB	Audio level meter	Rec	None signal
		TP1(+), TP2(-)
	• Connection Method

	S/N: 97P65064HA	R290	Audio LEVEL METER
	HEAD AMP PCB
	3.0mVrms			+
				–
			A/CHEAD
				TP1
			TP2	(+)
			(–)
		TOP VIEW

• Adjustment Procedure

1)Set the TV/LINE to LINE mode.

2)Set the input to open mode

3)Connect the Audio level meter to both TP1 and TP2

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

5)Adjust R290 to obtain 3.0 mVrms.

4

2-3. IF MODULE CIRCUIT ADJUSTMENT METHOD

2-3-1. PAL B/G 2 CARRIER SYSTEM

1. 32.4MHz TRAP

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L101	TP1	Oscilloscope	EE Mode	Refer to the
			Signal Gen		followings
	• Connection Method

PIF PCB (Component Side)	minimum

	#2
P102
#3	P101
	L108

		L101 TP1				L109
L104					TP3
			Z101	IC102	TP4	IC103
	L103
L105			TP2
IC101				TP6 TP7		L110
#2	#3
GND	OUT			fc: 32.4 MHz (No modulation)
				Output Level: 80dBµV (75		loaded)
SIGNAL
GENERATOR

CH-1

Oscilloscope

• Adjustment Procedure

1)Supply +12V to pin No.1, and GND to Pin No 2. of 102

2)Connect the signal generator output to pin 3 and GND to pin 2 of P102.

3)Connect the oscilloscope to TP1.

4)Adjust L101 until the level of signal becomes minimum.

5

2. PIF COIL

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L104	TP2	Oscilloscope	EE Mode	Refer to the
			Signal Gen		followings

• Connection Method

PIF PCB (Component Side)
	#2
P102
#3			L108		P101
minimum
	L101	TP1			L109
				TP3
		Z101	IC102	TP4	IC103
	L103
L105	TP2
IC101			TP6 TP7		L110
#2	#3
GND	OUT		fc: 38.9MHz
			Output Level: 80dBµV (75		loaded)
SIGNAL
GENERATOR

CH-1

Oscilloscope

• Adjustment Procedure

1)Supply +12V to pin No.1, and GND to Pin No 2. of 102

2)Connect the signal generator output to pin 3 and GND to pin 2 of P102.

3)Connect the oscilloscope to TP2.

4)Adjust L104 to obtain the minimum DC voltage of TP2.

6

3. AFT COIL

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L105	“A” point	Oscilloscope	EE Mode	Refer to the
			Signal Gen.		followings

• Connection Method

PIF PCB (Component Side)

(Test circuit)

Vcc+12V

		#2
P102			43k
#7	#3	P101
		L108

		L101 TP1				L109	#7
								CH-1
L104					TP3
				IC102		IC103	33k	Oscilloscope
			Z101		TP4
	L103							"A"
L105			TP2
IC101				TP6 TP7		L110	18k
				2.3±0.5V				GND
#2	#3
GND	OUT			fc: 38.9MHz, fm: 15.625KHz (30% AM Modulation)
SIGNAL				Output level: 80dBµV (75 loaded)
GENERATOR

• Adjustment Procedure

1)Supply +12V to pin No.1, and GND to Pin No 2. of 102

2)Connect the signal generator output to pin 3 and GND to pin 2 of P102.

3)Connect the Test circuit to pin No. 7 of P102

4)Connect the oscilloscope to “A” point and GND

5)Adjust L105 to obtain 2.3V DC Voltage at the "A" point

7

4. SOUND CARRIER

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L190	IC102 #15	Oscilloscope	EE Mode	Refer to the
			Signal Gen.		followings

• Connection Method

minimum			PIF PCB (Component Side)
noise
level					CH-1
	#2				Oscilloscope
P102
#3			L108		P101
	L101	TP1			L109
L104				TP3
		Z101	IC102	TP4	IC103
	L103
L105	TP2
IC101			TP6 TP7		L110
#2
GND	OUT
SIGNAL				fc: 38.9MHz, fm: 15.625KHz (30% AM Modulation)
				Output level: 80dBµV (75 loaded)
GENERATOR

• Adjustment Procedure

1)Supply +12V to pin No. 1, and GND to pin No. 2 of P102 Supply +5V to pin No. 3, and GND to pin No. 1 of P101

2)Connect the signal generator output to pin 3 and GND to pin 2 of 102.

3)Connect the oscilloscope to pin NO.15 of IC102.

4)Adjust L108 to obtain the minimum Noise, minimum Level of pin NO.15 of IC102.

8

5. LEFT, RIGHT SOUND

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L109 (LEFT)	TP3	Oscilloscope	EE Mode	Refer to the
	L110 (RIGHT)	TP4	Signal Gen.		followings
	• Connection Method

PIF PCB (Component Side)

LEFT

P102

GND

			L108			P101
	L101	TP1				L109
L104					TP3
		Z101	#15	IC102		IC103
					TP4
	L103
L105	TP2
	IC101		TP6 TP7
	#15					RIGHT
GND	OUT

	SIGNAL	fc: 5.5MHz (LEFT) fm: 1KHz (50KHz FM Modulation)
		5.74MHz (RIGHT)
	GENERATOR
		Output level: 100dBµV (75	loaded)

CH-1

Oscilloscope

CH-2

• Adjustment Procedure

1)Supply +12V to pin No. 1, and GND to pin No. 2 of P102 Supply +5V to pin No. 3, and GND to pin No. 1 of P101

2)Connect the signal generator output to pin NO.15 of IC102 and GND.

3)Connect the oscilloscope to TP3, TP4.

4)Adjust L109 to obtain the maximum level of TP3.

5)Adjust L110 to obtain the maximum level of TP4.

9

6. RF AGC

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	R190	JPT02	Oscilloscope	EE Mode	Refer to the
			PM5418 Gen.		followings

• Connection Method

MAIN PCB

RF OUT	PM5418

Modulator ANT IN

RF102

CH-1

RF101 JPT02

Oscilloscope

R190

RF103

6.0±0.2V

RF Signal : PAL B/G (Color Bar or 100% white)

CH : 21 CH (471.25MHz)

UHF BAND

Input Level : 70±1 dBµV

(75 Loaded)

• Adjustment Procedure

1)Turn on the VCR, Tuning CH21 (471.25MHz)

2)Connect the signal generator output to ANT INPUT of RF 102 (Modulator)

3)Connect the oscilloscope to JPT02

4)Adjust R190 to obtain 6.0±0.2V DC.

10

2-3-2. PAL B/G, I NICAM SYSTEM

1. PIF COIL (NICAM)

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L104	TP2	Oscilloscope	EE Mode	Refer to the
			Signal Gen.		followings

• Connection Method

	#2
	#3	P102		TP1	J8	J9	97P651111A				P101
					L108		J10	J11
			R103
									D102		C181
J1					J7
								J12	J13
minimum				IC102				J15		D101
										R163
L104					J6				X102		L112
							TP4				CH-1
											Oscilloscope
	L103									C178	C176
	TP2
					J4					C182
									2730
L105	C106	C107	Z101	C115	TP3					C153
	IC101				J19				IC104

					fc: 39.5MHz (I)
	GND			OUT
	SIGNAL				38.9MHz (B/G)
					Output Level: 80dBµV (75 loaded)
	GENERATOR

• Adjustment Procedure

1)Supply +12V DC to Pin No.1, and GND to Pin No 2. of 102

2)Connect the signal generator output to pin 3 and GND to pin 2 of P102.

3)Connect the oscilloscope to TP2.

4)Adjust L104 to obtain the minimum DC voltage of TP2.

11

2. AFT COIL

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L105	“A” point	Oscilloscope	EE Mode	Refer to the
			Signal Gen.		followings

• Connection Method

(Test circuit)

#2

Vcc+12V

P102

TP1

J8

J9

97P651111A

P101

43k

#3

L108

J10

J11

R103

#7

C181

J1

J7

D102

CH-1

Oscilloscope

J12

J13

IC102

33k

J15

R163

D101

2.3±0.5V

L112

"A"

J6

TP4

X102

L104

18k

L103

C178

C176

TP2

J14

J4

C182

27 30

L105

C106

C107

Z101

C115

TP3

C153

GND

IC101

J19

IC104

					fc: 39.5MHz (I)
	GND			OUT
	SIGNAL				fc: 38.9MHz (B/G)
					fm: 15.625KHz (30% AM MODULATION)
	GENERATOR
					Output Level:80 dBµV (75 loaded)

• Adjustment Procedure

1)Supply +12V DC to Pin No.1, and GND to Pin No 2. of 102

2)Connect the signal generator output to pin 3 and GND to pin 2 of P102.

3)Connect the test circuit to pin No.7 of P102

4)Connect the oscilloscope to “A” point and GND

5)Adjust L105 to obtain 2.3V DC voltage at the "A" point

12

3. SOUND CARRIER (NICAM)

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L108	TP3	Oscilloscope	EE Mode	Refer to the
			Signal Gen		followings
	• Connection Method

	minimum
	noise
	level
	#2
				J8	J9	97P651111A				P101
	#3
				L108		J10	J11
			R103
	S2
										C161
								D102
J1					J7
	J3
							J12	J13
				IC102			J15		R163
									D101
										L112
				J6		TP4		X102
L104
	L103								C178	C176
	TP2
							J14
				J4	TP3				C182
								27 30	C155
L105	C106	C107	Z101	C115
	IC101				J19			IC104

	#2	#3
	GND	OUT	fc: 39.5MHz (I)
	SIGNAL		38.9MHz (B/G)
			fm: 15.625KHz (30% AM MODULATION)
	GENERATOR
			Output Level:80 dBµV (75 loaded)

CH-1

Oscilloscope

• Adjustment Procedure

1)Supply +12V DC to Pin No.1 and GND to pin No. 2 of P102

2)Supply +5V DC to Pin No.3 GND to Pin No. 1 of P101.

3)Connect the signal generator output to pin 3 and GND to pin 2 of p102

4)Connect the oscilloscope to TP3.

5)Adjust L108 to obtain the minimum noise, minimum level of TP3.

13

4. 5.5 (6.0) MHz SOUND

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	L109	TP4	Oscilloscope	EE Mode	Refer to the
			Signal Gen		followings
	• Connection Method

L109

		P102		TP1	J8	J9	97P651111A				P101
	#3
					L108		J10	J11
			R103
									D102		C181
J1						J7
								J12	J13
				IC102				J15		R163
										D101
											L112
					J6		TP4		X102
L104
	L103									C178	C176
	TP2						TP3
								J14
										C182
					J4
									27 30	C153
L105	C106	C107	Z101	C115
	IC101					J19			IC104

							fc: 6.0MHz (I)
	GND				OUT
							5.5MHz (B/G)
	SIGNAL
							fm: 1KHz (50kHz FM MODULATION)
	GENERATOR
							Output Level: 100dBµV (75 loaded)

• Adjustment Procedure

1)Supply +5V DC to Pin No.3 GND to Pin No. 1 of P101.

2)Connect the signal generator output to TP3 and GND to TP1.

3)Connect the oscilloscope to TP4.

4)Adjust L109 to obtain the maximum level of TP4.

CH-1

Oscilloscope

14

5. RF AGC

	Adjustment Parts	Checking Point	Measuring Equipment	Condition of Adj.	Input Signal
	R190	JPT02	Oscilloscope	EE Mode	Refer to the
			PM5418 Gen		followings

• Connection Method

MAIN PCB

RF OUT	PM5418

Modulator ANT IN

RF102

CH-1

RF101 JPT02

Oscilloscope

R190

RF103

6.0±0.2V

RF Signal : PAL B/G (Color Bar or 100% white)

CH : 21 CH (471.25MHz)

UHF BAND

Input Level : 60 dBµV (I) 63 dBµV (B/G)

(75 ohm Loaded)

• Adjustment Procedure

1)Turn on the VCR. Tuning CH21 (471.25MHz)

2)Connect the signal generator output (PM5418 pattern Gen) to ANT INPUT of RF102 (Modulator)

3)Connect the oscilloscope to JPT02

4)Adjust R190 to obtain 6.0±0.2V DC.

15

SECTION 3. TROUBLE SHOOTING FLOW CHART

3-1. 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 IC801, check FUSE and Cement resistance surely.

A. CHECKING THE PRIMARY CIRCUIT.

	NO output Voltage
	YES
	Prepare the instrument
	connecting the insulating trans.
	YES
	Check F801 FUSE
	YES
		NO
	Is voltage applied to D801?		Check D801, L801 & L802
	YES
		NO
	Is voltage applied to the		Check R802
	both terminals of C807?
	YES
	Check power module

16

B. POWER MODULE (M801) CHECK

No Voltage

output

Is voltage supplied

Via CN11?

YES

The voltage of #1 of

IC11 is 5.7V and stable

NO

The voltage of #1 of IC11 fluctuate

in 4.8V~5.7V

YES

Measure resistance between GND of CN21 and each terminal

of CN21

Resistance >> 100

The 12DC of each wire of T11 is ok

YES

Primary parts is ok

YES

Secondary parts ok

NO	Check F801, L801,
	L802, D802

YES	Check the secondary
	circuit

NO	Check the pattern
	and T11, L12, IC11

	Terminal open and		The voltage	NO		Check the
	measure the output					parts outside
			is ok
	Voltage					module
			YES
NO
	Change T11		Check the Diode,
			Condenser inside
			Module

NO	Change parts
	out of order

NO	Change parts
	out of order

17

3-2. LOGIC CIRCUIT

A.

Digitron does not operate.

Is +5V supplied to pin 8 of IC701?

YES

Is -28V supplied to pin 11 of IC701?

YES

Are -20 and -16.5V supplied to pin 1 and 35 of G701?

YES

Are CLK signals supplied to pin ), I

and i, of IC701?

YES

Is 5V at pin 7 of

IC701?

YES

Check X701

YES

Check IC701

and change.

NO	Is +5.8V supplied	NO	check power circuit
	from D713 cathod

NO	Is -28V at D650	NO	Check D814 and
	anode		primary power circuit.

YES

Check the connector and pattern.

NO	Check the power
	module

NO

Check IC601

NO

Change

NO

Change

18

BB..

Digitron is lit keys do not operate.

	Is each key pulse	NO
			Check key matrix
	applied to pin 2 , 3
			circuit.
	12 and 13 of IC701?
	YES

Check the pin serial of pin 19 , 22 ~ 24 of IC701.

CC..

Power compensation does not operated.

When mains is unplugged is 3.6V at pin 26 and 81 of IC601?

YES

Issignal applied to pin 42 and 43 of IC601?

YES

Is 5V at pin 37 of IC601

YES

Check IC601

NO	Check C623

NO

Check x602

NO	Check reset circuit
	IC604

19

3-3. SERVO SYSCON CIRCUIT

A.

Playback picture is not good.

Noise appears	NO
		Adjust
although adjusting		tracking
tracking.
YES

Noise shakes up and down on the screen.

YES

Is CTL pulse out from pin 73 of IC601.

YES

Is CTL pulse input to pin 71 and 72 of IC601

YES

The voltage of pin

91of IC601 is not changed.

YES

Check IC601

	NO	Noise appears
		although change
		cassette tape.

NO CTL HEAD height is normal and there is

not dust.

YES

NO

Check C508, C509

NO	check R518
	and C511

YES	Check and
	re-adjust the
	Path of Deck.

NO	Adjust the HEAD
	height and remove
	dust

Check circuit adjacent to IC601

20

B.

Playback picture is not good.

YES

Noise appears on the screen on the whole.

YES

Are SW pulse and

HA SW applied to

HeadAmp circuit?

YES

Is Enve.wavefrom supplied to at pin 4 of

PT01

YES

Check video circuit.

C.

Auto stop during playback

YES

NO	Check flow A

NO	Is SW pulse supplied		NO	Check D.PG input
	from pin 18 of IC601?			and connector.
	YES
NO
	Check pattern

	Check connector, Head	NO
			Change head
	Amp and Head dust.

	Is Reel pulse	NO
			Check reel sensor.
	applied to pin 5 and
	6 of IC601?
	YES

Is D.FG applied to	NO	Check connector
pin 67 of IC601		D.FG circuits.

YES

Check IC601

21

D.

Drum M/T loading stops.

NO

Is Motor 12V supplied?

YES
	NO
Is pin 67 D.FG of
IC601 supplied.
YES
	NO
Is pin D.PWM (pin 4 )
of IC601 supplied?
YES
Check connector
and Motor.

E.

Capstan M/T loading stops.

	YES
		NO
	Is Motor 12V supplied?
	YES
		NO
	Is the input of pin 1
	of P501 2V-3.5V?
	YES
		NO
	Is pin 18 of P601 2.5V
	YES
		NO
	Is pin 3 (C.PWM)
	of IC601 Supplied?
	YES
	Check connector
	and Motor

Check Q851 of

power circuit.

Check C505, R506, R507

and C516

Check IC601

Check power circuit.

Check circuit of R510, R511, R512.

Check R508, R509

Check IC601

22

F.

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

NO
	NO
Is C. Sync applied to		Check C. Sync of
pin 93 of IC601?		VIDEO IC and Pattern

YES

Check Motor.

G.

Emergency mode when plugging (Power cord)

Is EVER 5V supplied?	NO
YES

NO

Does X601 crystal osciliate?

YES

	Do S/DATA, CLK and RDY	NO
	Signals of IC601 exchange
	with IC701
	YES
		NO
	Is CAM SW DATA Correct?
	YES

Check IC602.

YES

Check IC 601.

Check power circuit.

Check IC601 and X601.

Check IC701 when S.RDY Signal is supplied.

Check IC601 when S.RDY Signal is not supplied.

Recheck connector and CAM SW contact.

23

H.

Cassette is not inserted.

Is Motor 12V supplied?

YES

CAM DATA is changed when CST IN?

YES

Is 5V applied to

pin 4 of IC602 when CST IN?

YES

Chek IC602

NO	Check Q851 of power
	circuit

NO	Check connector.	NO	Check DECK part.

NO	Is 5V supplied at	NO	Check PATTERN
	pin 45 of IC601?
	YES
	Check IC601

24