DAEWOO DV-F952N Service Manual
DAEWOO ELECTRONICS CO., LTD.
Service Manual
MODEL : DV-F952N
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
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 TRANSPOR T
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
Channel coverage
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.
Table 1: Rating for selected areas
* 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)
Insert load Z between B (earth ground, power cord plug
prongs) and exposed accesible parts. Use and AC
voltmeter to measure across both terminals of load Z.
See figure 2 and following table.
Table 2: Leakage current ratings 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.
Fig. 2
AC Line Voltage Region
Insulation Dielectric Clearance
Resistance Strength Distance (d), (d')
100V Japan ≥ 1 MΩ/500 VDC 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 VDC 3 kV AC 1 minute ≥ 6 mm (d)
200 to 240 V Australia ≥ 8 mm (d')
(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
parts
¡ ≤ 0.7 m A peak Antenna earth
110 to 130 V Europe ¡ ≤ 2 m A dc terminals
200 to 240 V Australia ¡ ≤ 0.7 m A peak
Other terminals
¡ ≤ 2 m A dc
Fig. 1
1k
1.5k
1.5kµF
2k
50k
d
Primary circuit termimals
Chassis
d'
a
Z
Exposed
accessible
part
AC Voltmter
(high impedance)
Earth Ground
power cord plug prongsB
2-1. SERVO CIRCUIT ADJUSTMENT METHOD
1. PLAYBACK PHASE
• Connection Method
• 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)
SECTION 2. ELECTRICAL ADJUSTMENT
Adjustment Parts Checking Point Measuring Equipment Mode Test Tape
JPT01
DP-2
Check
PT01 PIN ¤Ø
Oscilloscope Play
Modulator
JPT01
CH-1
OSCILLOSCOPE
CH-2
PT01
TOP VIEW
PATH JIG
6
4
2-2. AUDIO CIRCUIT ADJUSTMENT METHOD
1. AUDIO RECORD BIAS
• Connection Method
• 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.
5
TOP VIEW
R290
3.0mVrms
+
–
A/CHEAD
TP2
(–)
TP1
(+)
Audio LEVEL METER
S/N: 97P65064HA
HEAD AMP PCB
Adjustment Parts Checking Point Measuring Equipment Test Tape Input Signal
R290
A/C Head PCB
Audio level meter Rec None signal
TP1(+), TP2(-)
6
2-3. IF MODULE CIRCUIT ADJUSTMENT METHOD
2-3-1. P AL B/G 2 CARRIER SYSTEM
1. 32.4MHz TRAP
• Connection Method
• 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.
P102
L104
L105
IC101
#3
#2
L101
TP1
L108
TP2
L103
Z101
TP6 TP7
IC102
TP3
L109
P101
IC103
L110
TP4
minimum
CH-1
Oscilloscope
GND
OUT
#3
PIF PCB (Component Side)
SIGNAL
GENERATOR
fc: 32.4 MHz (No modulation)
Output Level: 80dBµV (75Ω loaded)
#2
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L101 TP1
Oscilloscope
EE Mode
Refer to the
Signal Gen followings
2. PIF COIL
• Connection Method
• 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.
7
P102
L104
L105
IC101
#3
#2
L101
TP1
L108
TP2
L103
Z101
TP6 TP7
IC102
TP3
L109
P101
IC103
L110
TP4
CH-1
Oscilloscope
GND
OUT
minimum
#3
PIF PCB (Component Side)
SIGNAL
GENERATOR
fc: 38.9MHz
Output Level: 80dBµV (75Ω loaded)
#2
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L104 TP2
Oscilloscope
EE Mode
Refer to the
Signal Gen followings
3. AFT COIL
• Connection Method
• 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
8
P102
L104
L105
IC101
#3
#2
L101
TP1
L108
TP2
L103
Z101
TP6 TP7
IC102
TP3
L109
P101
IC103
L110
TP4
2.3±0.5V
CH-1
Oscilloscope
GND
OUT
#3
#7
PIF PCB (Component Side)
#2
#7
SIGNAL
GENERATOR
fc: 38.9MHz, fm: 15.625KHz (30% AM Modulation)
Output level: 80dBµV (75Ω loaded)
43kΩ
33kΩ
18kΩ
"A"
Vcc+12V
GND
(Test circuit)
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L105 “A” point
Oscilloscope
EE Mode
Refer to the
Signal Gen. followings
4. SOUND CARRIER
• Connection Method
• 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.
9
P102
L104
L105
IC101
L101
TP1
L108
TP2
L103
Z101
TP6 TP7
IC102
TP3
L109
P101
IC103
L110
TP4
minimum
noise
level
CH-1
Oscilloscope
GND
OUT
PIF PCB (Component Side)
SIGNAL
GENERATOR
fc: 38.9MHz, fm: 15.625KHz (30% AM Modulation)
Output level: 80dBµV (75Ω loaded)
#3
#2
#2
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L190 IC102 #15
Oscilloscope
EE Mode
Refer to the
Signal Gen. followings
5. LEFT, RIGHT SOUND
• Connection Method
• 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.
10
P102
L104
L105
IC101
L101
TP1
L108
TP2
L103
Z101
TP6 TP7
IC102
TP3
L109
P101
IC103
L110
TP4
CH-1
Oscilloscope
CH-2
GND
OUT
LEFT
RIGHT
PIF PCB (Component Side)
SIGNAL
GENERATOR
fc: 5.5MHz (LEFT) fm: 1KHz (50KHz FM Modulation)
5.74MHz (RIGHT)
Output level: 100dBµV (75Ω loaded)
GND
#15
#15
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
6. RF AGC
• Connection Method
• 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.
11
CH-1
Oscilloscope
MAIN PCB
RF Signal : PAL B/G (Color Bar or 100% white)
CH : 21 CH (471.25MHz)
UHF BAND
RF102
RF101 JPT02
RF103
R190
6.0±0.2V
Input Level : 70±1 dBµV
(75Ω Loaded)
RF OUT PM5418
Modulator ANT IN
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
R190 JPT02
Oscilloscope
EE Mode
Refer to the
PM5418 Gen. followings
2-3-2. P AL B/G, I NICAM SYSTEM
1. PIF COIL (NICAM)
• Connection Method
• 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.
12
97P651111A
P102
P101
TP1
CH-1
Oscilloscope
SIGNAL
GENERATOR
GND
OUT
fc: 39.5MHz (I)
38.9MHz (B/G)
Output Level: 80dBµV (75Ω loaded)
minimum
#2
#3
R103
J1
L104
L105
Z101
C107
C106
IC101
TP2
J4
C115
TP3
J19
IC102
L108
J7
J12
J13
J15
C181
D101
R163
L112
X102
30 27
D102
C153
C182
C176C178
TP4
J11
J10
J9
J8
IC104
J6
L103
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L104 TP2
Oscilloscope
EE Mode
Refer to the
Signal Gen. followings
2. AFT COIL
• Connection Method
• 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
13
97P651111A
P102
P101
TP1
SIGNAL
GENERATOR
GND
OUT
fc: 39.5MHz (I)
fc: 38.9MHz (B/G)
fm: 15.625KHz (30% AM MODULATION)
Output Level:80 dBµV (75Ω loaded)
2.3±0.5V
#2
#3
R103
J1
L104
L105
Z101
C107
C106
IC101
L103
TP2
J4
C115
TP3
J19
IC102
L108
J7
J14
J12
J13
J15
C181
D101
R163
L112
X102
30 27
D102
C153
C182
C176C178
TP4
J11
J10
J9
J8
IC104
J6
CH-1
Oscilloscope
#7
43kΩ
33kΩ
18kΩ
(Test circuit)
Vcc+12V
GND
"A"
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L105 “A” point
Oscilloscope
EE Mode
Refer to the
Signal Gen. followings
3. SOUND CARRIER (NICAM)
• Connection Method
• 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.
14
97P651111A
P102
P101
TP1
CH-1
Oscilloscope
SIGNAL
GENERATOR
GND
OUT
fc: 39.5MHz (I)
38.9MHz (B/G)
fm: 15.625KHz (30% AM MODULATION)
Output Level:80 dBµV (75Ω loaded)
minimum
noise
level
#3
R103
S2
J3
J1
L104
L105
Z101
C107
C106
IC101
L103
TP2
J4
C115
J19
IC102
L108
J7
J14
J12
J13
J15
C161
D101
R163
L112
X102
30 27
D102
C155
C182
C176C178
TP4
J11
J10
J9
J8
IC104
J6
TP3
#3#2
#2
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L108 TP3
Oscilloscope
EE Mode
Refer to the
Signal Gen followings
4. 5.5 (6.0) MHz SOUND
• Connection Method
• 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.
15
97P651111A
P102
P101
TP1
CH-1
Oscilloscope
SIGNAL
GENERATOR
GND
OUT
fc: 6.0MHz (I)
5.5MHz (B/G)
fm: 1KHz (50kHz FM MODULATION)
Output Level: 100dBµV (75Ω loaded)
L109
#3
R103
J1
L104
L105
Z101
C107
C106
IC101
L103
TP2
J4
C115
J19
IC102
L108
J7
J14
J12
J13
J15
C181
D101
R163
L112
X102
30 27
D102
C153
C182
C176C178
TP4
J11
J10
J9
J8
IC104
J6
TP3
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
L109 TP4
Oscilloscope
EE Mode
Refer to the
Signal Gen followings
5. RF AGC
• Connection Method
• 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.
16
CH-1
Oscilloscope
MAIN PCB
RF Signal : PAL B/G (Color Bar or 100% white)
CH : 21 CH (471.25MHz)
UHF BAND
RF102
RF101 JPT02
RF103
R190
6.0±0.2V
Input Level : 60 dBµV (I)
63 dBµV (B/G)
(75 ohm Loaded)
RF OUT PM5418
Modulator ANT IN
Adjustment Parts Checking Point Measuring Equipment Condition of Adj. Input Signal
R190 JPT02
Oscilloscope
EE Mode
Refer to the
PM5418 Gen followings
17
4-2. CONNECTION DIAGRAM CIRCUIT(DV-F952N)
18
4-3. POWER CIRCUIT
19
4-4. SERVO-LOGIC CIRCUIT
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