Daewoo DF-4500 User manual

S /M No. : DF Q75D2001
S ervic e Manual
MODEL: DF-4500(S/P)
DF-4501(S/P)
DFX-4502(S/P)
DFX-4505(S/P)
JAN. 2006
DVDR + VCR Combi

1
SPECIFICATIONS...............................................................................................................2
TROUBLE SHOOTING....................................................................................................................3
WAVEFORMS................................................................................................................................24
CIRCUIT DIAGRAM.......................................................................................................................27
PCB CIRCUIT BOARD..................................................................................................................45
INSTRUMENT DISASSEMBLY.....................................................................................................48
ELECTRICAL PARTSLIST............................................................................................................49
CONTENTS

2
SPECIFICATIONS
General
Power requirements 200–240V~, 50/60 Hz
Power consumption 26W
Dimensions (approx.) 430 x 92 x 312 mm (w x h x d)
Mass (approx.) 4.96 kg
Operating temperature 41°F to 95°F (5°C to 35°C)
Operating humidity 5% to 90%
Signal system PAL Colour
Recording
Recording formats DVD Video Recording, DVD-VIDEO
Recordable discs DVD+R, DVD+RW, DVD-R, DVD-RW
Recordable time [DVD] Approx. 1 hour (HQ mode), 2 hours (SP mode), 4 hours (EP mode), 8 hours (SEP mode)
[VCR] SP: 3 hours (E-180), LP: 6 hours (E-180)
Video recording format
Sampling frequency 27MHz
Compression format MPEG 2
Audio recording format
Sampling frequency 48kHz
Compression format MPEG1 Layer2
VCR Specifications
Head system 4 Head Video, 2 Head Hi-Fi helical scan azimuth system
Timer 24-hour display type
Tape speed SP: 23.39 mm/sec, LP: 11.70 mm/sec
Tape width 12.7 mm
Rewind time less than 150 seconds (E-180)
Antenna 75 ohms (VHF/UHF)
Channel coverage VHF: 2-12, 13-20, 74-80 / UHF: 21-69 / CATV: 1-41
Frequency range 20Hz to 20kHz
Video S/N Over 43 dB (Standard recording)
Audio S/N Over 65 dB (Hi-Fi), Over 40 dB (Mono)
Resolution Over 240 lines (Standard recording)
DVD Specifications
Laser system Semiconductor laser, wavelength 650 nm
Frequency response DVD (PCM 48 kHz): 8 Hz to 22 kHz, CD: 8 Hz to 20 kHz
Video S/N More than 60 dB
Audio S/N More than 90 dB
Dynamic range More than 90 dB
Resolution Over 500 lines (HQ Recording)
Inputs/RF Output
RF In Antenna or CATV input 75 Ω
Video In 1.0 Vp-p, unbalanced
Audio In -8.8 dBm
DV In 4 pin (i.LINK/IEEE 1394 standard)
RF Output CH. 52(Australlia;CH.36)

TROUBLESHOOTING
3
1. No output voltage of POWER CIRCUIT
get input, DC 200~240 Valtage
1. POWER CIRCUIT

4
TROUBLESHOOTING
2. SYSTEM CIRCUIT

5
TROUBLESHOOTING
P303
Check REMOCON_IN
(Pin2)

6
TROUBLESHOOTING
B. Digital Board(Mpeg)

7
TROUBLESHOOTING
Noise appears on the
playback screen.
Is noise diminished by tracking
adjustment.
Noise band is trembled up and
down?
Re-adjust PATH.
IstheheightofCTLHEADnormal?
Nodust?
Is there problem in CTL Input circuit
and amplifier.
YES
NO
NO
NO
Is there CTL pulse at IC501
pin#97?
Check IC501.
Noise appears on the screen even
though changing tape.
Re-adjust the height of AC HEAD.
Remove the dust.
Check C510,R545~R547
IC 501 pin #94, 95, 97.
NO
Re-adjust PATH.
C-1. Bad playback quality (1)
YES
YES
YES
YES
Noise appears on the Full
playback screen.
Are SW pulse and HA SW normal?
Recheck step B-1
(Bad playback quallty (1)).
CheckHEADAMP connector
andHEAD.
YES
YES
NO
NO
ENVE Wave at P502 pin #4?
CheckVIDEOcircuit.
Are there SW, HA SW pulse at
IC501 pin #16, 18?
Check PCB Pattern.
CheckIC501.
C-2. Bad playback quality (2)
YES
NO
YES

8
TROUBLESHOOTING
No broadcasting signal
received
Is the output at IC501 pin#
61(CLK), 60 (DATA) normal?
Is SIF,Video output at TMI(RF101)
pin#16,19 normal?
Check IC 501.
Check IC 501.
Check P302
YES
YES
NO
NO
NO
Is Video Signal input at IC501
pin#56?
Is there Video output at P302
pin#5?
Check TMI (RF101) Block.
NO
Check Video Buffer Q670
D. No broadcasting signal received
YES
YES
YES

9
TROUBLESHOOTING
Cassette tape isn’t inserted.
Is 5V voltage obtained at Loading
parts IC501 pin#63?
Is 14V voltage obtained at
Capstan Motor P501 pin#2?
Check at EVER 14V
Check D825
ConnectCapstanand LoadingMotor.
Checkconnectorand CapstanMotor.
YES
NO
NO
NO
Is 13VvoltageobtainedatEach
partsofLoading Motor?
Replace Loading Motor.
Check D825 and POWER circuit.
E. No CASSETTE Loading
YES
YES
F. AUTO STOP in Playback mode
VCR stops automatically in
playback mode.
Check R544,C516 and P501
pin#11.
CheckS501,S502 REELSensor.
Is D.PG/FG pulse at IC501
pin#90 normal ?
Is C. FG pulse at IC501 pin#87
normal ?
IsthereREEL PulseatIC501
pin#79,80?
Checkandreplace IC501.
NO
YES
YES
YES
NO
Check C.FG(R543,C517) and
P501 pin#1.
NO

10
TROUBLESHOOTING
G. DRUM Motor stops
H. CAPSTAN doesn’t rotate
CAPSTAN doesn’t rotate.
Is EVER 14V voltage obtained
at P501 pin#2?
YES
NO
NO
NO
YES
YES
Is Capstan PWM fit to
IC501 pin#77?
Is 3.2V voltage obtained
at P501 pin#5?
Is 2.7V voltage obtained
at P501 pin#9?
Check P501 Connector and
Capstan Motor.
Check EVER 14V
(D825).
Check Capstan FG
(IC 501 pin# 87).
Check
R541,R540,R539,R538,C518
Check R537,R536,C521
DRUMMotorstops.
Is 14V voltage obtained at P501
pin#8?
YES
NO
NO
NO
YES
YES
Is DRUM PWM fit to IC 501
pin#76?
Is 2.6V voltage obtained at
P501 pin#12?
Check Capstan Motor and
DRUM Motor.
Check EVER 14V
(D825).
CheckDRUMPG/FG
(IC501pin# 90).
CheckR534,R535,C519,C520.
NO

11
TROUBLESHOOTING
3. VIDEO circuit
A. EE screen doesn’t appear
EE MODE Picture NG
Is Video signal input at
IC301 pin#48,50,52,54?
Is 5V supplied at
pin#42,55,72,91of IC301?
Is C.S, DATA, CLOCK signal
input pin#67,68,69 of IC301?
Check IF and SCART JACK.
Check POWER circuit.
Check IC501
pin #58,71,72
NO
YES
YES
NO
NO
YES
Is signal output from pin#65 of
IC301?
YES
NO Check IC301
pin#62 Q-V Sync.
Is signal input into pin#21
of P302?
YES
NO Check PCB Pattern.
Is signal output from pin#5
of P302?
YES
NO Check MPEG circuit.
Is signal output at IC301
pin#61?
YES
NO Check PCB Pattern.
Is signal input at IC301
pin#56?
Check RF Output. Check PCB Pattern & LINE
out.
YES
YES
Check IC301.
NO

12
TROUBLESHOOTING
B. Playback picture doesn’t appear
1) No VCR Playback Picture
YES
YES
Is Y SIGNAL output at IC301
pin#46?
Is VIDEO SIGNAL output at IC301
pin#65?
Check and Replace IC301.
PBvideosignal missing.
Is Envelope output from IC301
pin#79?
NO
NO
Same as EE MODE check.
Is 5V supplied at IC301 pin#91?
Is SW Pulse input at IC301
pin#70?
Is 5V obtained at IC301 pin#24,
42,55,72,91?
Check POWER 5V.
Check IC501 pin#18.
Clean head or Replace head.
Check POWER 5V.
NO
NO
Check PATTERN
NO
YES
YES
YES
YES
YES
YES
NO Does X301(4.43MHz)
oscillate?
Is Y SIGNAL input at IC301
pin#43? NO Check PATTERN
YES
NO Replace X301.
NO Check and replace IC301.

13
TROUBLESHOOTING
2)No DVD Playback Picture
Check RC54,(Digital board)
Check R385, R386,R387,R400,R404(Analog board)
2) No DVD Playback Picture

14
TROUBLESHOOTING
Is +5V supplied at IC301 pin#91? NO
NO
YES
YES
Is VIDEO SW Pulse input at IC301
pin#70?
Is REC signal output from IC301
pin#94,95,89,90?
SP MODE: 89,90 Pin
LP MODE: 94,95Pin
Check video HEAD and Connector.
Is signal input into IC301
pin# 48,50,52,54,56?
Check POWER circuit.
Check IC501 pin#18.
Record video signal poor.
Check EE MODE.
YES
Is luminance and color signal
output from IC301 pin#78?
Replace IC301.
NO
NO
YES
C. No Recording
1) VCR Part
YES
Is IC301 pin#80 REC(H) HIGH? Check IC501 pin#1.
NO

15
TROUBLESHOOTING
DVD is not recording
Check RC54.(Digital board)
Check R385, R386, R387, R400,
R404(Analog board)
at
2) DVD Part

16
TROUBLESHOOTING
4. AUDIO (Hi-Fi MODEL)
No sound in RF E-E mode
Is Audio signal output at IC602 pin
#3, 13?
A. No sound in E-E mode
a. RF E-E
Is Audio signal output at IC251
pin#16,17? Are CLK and DATA obtained at
IC251 pin#42,43?
NO
Is 5V obtained at IC251 pin#40?
Replace IC251.
YES
YES
Is 12V obtained at IC251 pin#34?
NO
YES Check POWER circuit.
YES
Is 5V obtained at IC051 pin#1? Check Power circuit.
NO
Is there SIF signal at IC051 pin#2
in RF mode? Check RF101.
NO
YES
Is there SIF signal out at IC051
pin#30, 31? Check IC051.
NO
YES
YES
Check Digital board(No sound in
E-E mode)
NO
Check Output JACK.
YES

17
TROUBLESHOOTING
b. AV1 E-E
No sound in AV1 E-E mode.
NO Check Input AV1 JACK
Is Audio signal at IC251 pin#6, 7?
Is Audio signal output at IC602 pin
#3, 13?
Is Audio signal output at IC251
pin#16,17? Are CLK and DATA obtained at
IC251 pin#42,43?
NO
Is 5V obtained at IC251 pin#40?
Replace IC251.
YES
YES
Is 12V obtained at IC251 pin#34?
NO
YES Check POWER circuit.
YES
YES
Check Output JACK.
YES
Check Digital board(No sound in
E-E mode)
NO

18
TROUBLESHOOTING
c. AV2 E-E
No sound in AV2 E-E mode.
NO Check Input AV2 JACK
Is Audio signal at IC251 pin#8, 9?
Is Audio signal output at IC602
pin #3, 13?
Is Audio signal output at IC251
pin#19, 20? Are CLK and DATA obtained at
IC251 pin#42,43?
NO
Is 5V obtained at IC251 pin#40?
Replace IC251.
YES
YES
Is 12V obtained at IC251 pin#34?
NO
YES Check POWER circuit.
YES
YES
Check Output JACK.
YES
Check Digital board(No sound in
E-E mode)
NO

19
TROUBLESHOOTING
d. FRONT E-E
No sound in FRONT E-E
mode.
NO Check Input FRONT JACK
Is Audio signal at IC251
pin#10,11?
Is Audio signal output at IC602 pin
#3, 13?
Is Audio signal output at IC251
pin#19, 20? Are CLK and DATA obtained at
IC251 pin#42,43?
NO
Is 5V obtained at IC251 pin#40?
Replace IC251.
YES
YES
Is 12V obtained at IC251 pin#34?
NO
YES Check POWER circuit.
YES
YES
Check Output JACK.
YES
Check Digital board(No sound in
E-E mode)
NO