DAEWOO DV-F462N, DV-F262N, DV-F482N, DV-F282N, DV-F542N Service Manual
...
DAEWOO ELECTRONICS CO., LTD.
Service Manual
MODEL : DV-F462N/262N
DV-F482N/282N
DV-F542N/342N
DV-F442N/242N/X
POWER
EJECT
REC /OTR
CH/TRACK
REW FF
PLAY
STOP
DV-F46N/26N
DV-F48N/28N
DV-F54N/34N
DV-F44N/24N/X
NEW PCB Model of
SPECIFICATIONS
Power Source: 120V 60Hz
Power Consumption: Approx. 17 watts
Temperature: 41°F to 104°F
Television System: USA-525 lines, 60 fields NTSC standard
Video Signal System: NTSC type color signal
Video Recording System: Luminance: FM azimuth recording color phase shift and
converted subcarrier direct recording
Scanning System: Rotary, slant azimuth, helical scanning system, 2 head,
4 head double Azimuth
Tuner: 181 Channel Freq. Synthesized
VHF : 2-13
UHF : 14-69
CATV: 14-36(A)-(W), 37-59(AA)-(WW), 60-85(AAA)-(ZZZ),
86-94(86)-(94), 95-99(A-5)-(A-1), 100-125(100)-(125),
01(5A)
Audio Track: 1 Track
Tape Speed: SP: 1-5/16"/sec.
LP: 21/32"/sec.
EP: 7/16"/sec.
Visual Search Speed: SP-3 X Normal Speed
LP-5 X Normal Speed
EP-5 X Normal Speed
Record/Playback Time: Max. 8 Hours T-160 at EP
FF/REW Time: Less than 5.0 min. with T-120 tape
Heads: Video: 2 rotary heads (VR-4250), 4 head double azimuth (VR-4450)
Audio/Control: 1 stationary head
Erase: 1 full track erase
Modulator: Signal Strength: 66 dBµ/75 ohm
RF Channel Output: Channel 3 or 4, switchable
Input Level: Video: 1.0Vp-p 75 ohm (RCA)
Audio: -8dB/50K ohm (RCA)
Output level: Video: 1.0Vpp 75 ohm (RCA)
Audio: –6dB/1K ohm (RCA)
Weight: 9.1 Lbs
Dimensions: 14.2(W) X 12.3(D) X 3.5(H) Inches
1
• 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 tes
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.
Table 1: Rating for selected areas
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)
Insert load Z between B (earth ground, power cord plug
prongs) and exposed accessible parts. Use and AC
voltmeter to measure across both terminals of load Z.
See figure and following table.
Table 2: Leakage current ratings for selected areas
Note: This is table unofficial and for reference only. Be sure to confirm the precise values for your particular country and
locality.
Fig. 1
Fig. 2
AC Line Voltage Region
Insulation Dielectric Clearance
Resistance Strength Distance (d), (d')
100V Japan ≥ 1 MΩ/500 VDC 1kV 1 minute ≥ 3 mm
110 to 130V
USA &
– – –
900V 1 minute ≥ 3.2mm
Canada
* 100 to 250 V
≥ 6 mm (d)
South
≥ 10 MΩ/500 V DC 4 kV 1 minute ≥8 mm (d')
America
(a: Power cord)
AC Line Voltage Region
Earth Ground
Load Z Leakage Current (i)
(B) to:
100V Japan ¡ ≤ 1m A rms
Exposed accessible
parts
110 to 130 V USA & ¡ ≤ 0.5 m A rms Exposed accessible
Canada parts
¡ ≤ 0.7 m A peak Antenna earth
100 to 130 V South ¡ ≤ 2 m A dc terminals
200 to 250 V America ¡ ≤ 0.7 m A peak
Other terminals
¡ ≤ 2 m A dc
2
TABLE OF CONTENTS
SPECIFICA TIONS.................................................................................................................................................................1
CONTROLS AND FUNCTIONS.....................................................................................................................................4
ELECTRICAL ADJUSTMENTS
ADJUSTMENT PROCEDURES ...........................................................................................................................................................7
MAJOR COMPONENTS COCATION GUIDE.....................................................................................................................................8
BLOCK DIAGRAM
VIDEO....................................................................................................................................................................................................9
2HD PRE-AMP....................................................................................................................................................................................10
4HD PRE-AMP....................................................................................................................................................................................11
AUDIO .................................................................................................................................................................................................12
SYSCON/SERVO/TIMER & LOGIC..................................................................................................... ..............................................13
OSD.....................................................................................................................................................................................................14
PIF & INPUT.................................................................................................................... ....................................................................15
POWER...............................................................................................................................................................................................16
PRINTED CIRCUIT BOARDS
MAIN PCB...........................................................................................................................................................................................17
LOGIC PCB..................................................................................................................................................................................18~19
HEAD AMP PCB.................................................................................................................................................................................20
SCHEMA TIC DIAGRAMS
4HD VIDEO SCHEMATIC...................................................................................................................................................................21
2HD VIDEO SCHEMATIC...................................................................................................................................................................22
4HD PREAMP SCHEMATIC..............................................................................................................................................................23
2HD PREAMP SCHEMATIC..............................................................................................................................................................24
AUDIO SCHEMATIC...........................................................................................................................................................................25
LOGIC SCHEMATIC....................................................................................................................................................................26~27
SYSCON/SERVO/TIMER SCHEMATIC............................................................................................................................................28
OSD SCHEMATIC..............................................................................................................................................................................29
PIF & INPUT SELECTOR SCHEMATIC.............................................................................................................................................30
POWER SUPPLY SCHEMATIC (I).....................................................................................................................................................31
POWER SUPPLY SCHEMATIC (II)....................................................................................................................................................32
CONNECTION DIAGRAM..................................................................................................................................................................33
WA VEFORM & VOLTAGE CHAR T
LUMA/CHROMA WAVEFORMS.................................................................................................................................................34~35
AUDIO WAVEFORMS ........................................................................................................................................................................36
SERVO WAVEFORMS .......................................................................................................................................................................37
SERVO/SYSCON/TIMER VOLTAGE CHARTS ..........................................................................................................................38~40
AUDIO VOLTAGE CHARTS...............................................................................................................................................................40
POWER VOLTAGE CHARTS.............................................................................................................................................................40
OSD VOLTAGE CHARTS...................................................................................................................................................................41
VIDEO (LUMA/CHROMA) VOLTAGE CHARTS ................................................................................................................................42
PRE AMP VOLTAGE CHARTS..........................................................................................................................................................43
PIF & INPUTS SELECT VOLTAGE CHART.......................................................................................................................................44
EXPLODED VIEW AND P AR TS LIST..................................................................................................................45~51
MACHANICAL EXPLODED VIEW .......................................................................................................................52~53
DISASSEMBLY...............................................................................................................................................................54~58
ELECTRICAL REPLACEMENT P AR TS LIST.................................................................................................59~66
3
KEY TO ABBREVIA TIONS
PREVENTIVE CHECKS AND SERVICE INTERVALS
: CHECK, CLEAN O : REPLACE
A AC : Alternating Current
A/C : Audio/Control
ACC : Automatic Color Control
A.E. : Audio/Erase
AFC : Automatic Frequency Control
AFT : Automatic Fine Tuning
AGC : Automatic Gain Control
AMP : Amplifier
ANT : Antenna
APC :Automatic Phase Control
B BGP : Burst Gate Pulse
B.P.F : Band Pass Filter
B/W : Black and White
C CAP : Capstan
CAR : Carrier
CCD : Charged Coupled Device
CH : Channel
CLK : Clock
COMP : Comparator
C ROTARY : Color rotary
C SYNC : Composite Sync
CONV : Converter
CTL : Control
CYL : Cylinder
D DC : Direct Current
DC ENVE : DC Envelope Voltage
DET : Detector
DEV : Deviation
DOC : Drop-Out Compensation
E EE : Electric to Electric
EP : Extended Long Play
EQ : Equalizer
F FG : Frequency Generator
FM : Frequency Modulation
FSC : Frequency Sub Carrier
FWD : Forward
G GND : Ground
H H.P.F : High Pass Filter
H.A.SW : Head Amp Switch
H. SYNC : Horizontal Sync.
I IF : Intermediate Frequency
L LED : Light Emitting Diode
LIMIT : Limiter
LM : Loading Motor
LOAD : Loading
LP : Long Play
L.P.F : Low Pass Filter
LUMI : Luminance
M MM : Monostable Multivibrator
MOD : Modulator, Modulation
MS SW : Mech State Switch
N NC : Non Connection
O OSC : Oscillator
OSD : On-Screen Display
P PB : Playback
PB-C : Playback-Chrominance
PB-Y : Playback-Luminance
PCB : Printed Circuit Board
PG : Pulse Generalor
PIF : Picture Intermediate Frequency
PLL : Phase Lock Loop
PS : Phase Shift
PWM : Pulse Width Modulation
Q Q.V. : Quasi Vertical Sync
R REC : Recording
REC-C : Recording-Chrominance
REC-Y : Recording-Luminance
REEL S : Reel Sensor
REF : Reference
REW : Rewind
REG : Regulated, Regulator
RF : Radio Frequency
S SEL : Select, Selector
SIF : Sound Intermediate Frequency
SP : Standard Play
STB : Serial Strobe
SVC : Service
SW : Switch
SYNC SEP : Sync Separator, Separation
T TR : Transistor
TRACK : Tracking
TRICK : Trick Playback
TP : Test Point
U UNREG : Unregulated
V VCO : Voltage Controlled Oscillator
VIF : Video Intermediate Frequency
VFD : Vacuum Fluorescent Display
VR : Variable Resistor
V-SYNC : Vertical-Synchronization
VXO : Voltage Controlled Oscillator
Y Y/C : Luminance/Chrominance
TIME (OPERATING HOURS)
PARTS NAME 1000 2000 3000 4000 5000
DRUM ASS'Y ƒN O ƒN O ƒN
CAPSTAN MOTOR O O
L/C BRKT ASS'Y O O
REEL BELT O O
IDLER PLATE ASS'Y ƒN O
REEL TABLE O
T-SUB BRAKE ASS'Y O O
BAND BRAKE ASS'Y O O
S-MAIN BRAKE ASS'Y O O
T-MAIN BRAKE ASS'Y O O
PINCH ROLLER ASS'Y ƒN O ƒN
AC HEAD ASS'Y O
FE HEAD O
REEL GEAR ASS'Y ƒN O
4
CONTROLS AND FUNCTIONS
POWER
EJECT REC/OTR
REW FF
PLAY
STOP
CH./TRACKING
FRONT
DV-F462/262N
DV-F482/282N
POWER
CH REC
STOP PLAYEJECT
REW FF
5
PAUSE
/ STILL
STOP
PLAY
POWER
CH CH
EJECT
REC/OTR
FRONT
DV-F542/342N
DV-F442/242N/X
POWER
EJECT
CH/TRACK
PLAY
REW FF
STOP
REC / OTR
6
ANT.IN
RF OUT
VIDEO AUDIO
IN
OUT
CH.4CH.3
REAR
7
ELECTRICAL ADJUSTMENTS
ADJUSTMENT PROCEDURES
Read and perform these adjustments when repairing the
circuits or replacing electrical parts or PCB assemblies.
CAUTION: Inferior silicon grease can damage transistors.
When replacing transistors, use only specified
silicon grease.
Remove all old silicon before applying new
silicon.
1. PG SHIFTER
CONDITIONS
MODE-PLAYBACK
Input Signal-Alignment Tape (DN-1).
INSTRUCTIONS
1. Connect CH-1 on the oscilloscope to pin ¤Ø of PT01
and CH-2 to Video output JACK.
2. Adjust R595 so that the waveform of the oscilloscope
measures 6.5±0.5(H) at both leading and trailing edges.
(Refer to Fig. 5-1-A, B)
2. COMB FILTER
CONDITIONS
MODE-STOP
Input Signal-NTSC Multiburst (VIDEO IN JACK)
INSTRUCTIONS
1. Connect the video signal generator to VIDEO IN JACK.
2. Connect CH-1 on the oscilloscope to TJ303 and CH-2
to TJ304.
3. Trigger the scope with CH1.
4. Adjust R494 until the 3.58MHz component of multiburst
signal becomes minimum. (Refer to Fig. 5-2)
3. AUDIO BIAS
CONDITIONS
MODE-RECORD (SP MODE)
Input Signal-Audio Signal : No Signal
INSTRUCTION
Connect the AC voltmeter as shown, then adjust the
voltage to 3.0±0.1mVrms with R292 (Refer to fig. 3-6).
6.5H
CH-1
CH-2
Fig 5-1-A
Fig 5-1-B
Fig 5-2
A/C Head.
AC Voltmeter
TP2
(GND)
TP1
Fig 5-3
6.5H
CH-2
CH-1
8
MAJOR COMPONENTS LOCA TION GUIDE
VR595VR292
FRONT
A/V JACK
DECK ASSEMBLY
PT01
VR494
POWER
SUPPLY
TJ303
TJ304
9
BLOCK DIAGRAMS
VIDEO
10
2HD PRE-AMP
11
4HD PRE-AMP
12
AUDIO
13
SYSCON/SERVO/TIMER & LOGIC
14
OSD
15
PIF & INPUT
16
POWER
17
PRINTED CIRCUIT BOARDS
MAIN PCB
18
LOGIC PCB
DV -F462N/262N
DV -F482N/282N
19
DV -F542N/342N
DV -F442N/242N/X
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