Samsung SV-4000W User manual

VIDEO CASSETTE RECORDER
SV-4000W
SERVICE Manual
VIDEO CASSETTE RECORDER CONTENTS
For mechanical disassembly and adjustment, refer to the “Mechanical Manual”
(DX7-R/RC, DX8-R/RC AC68-20316A).
1. Precautions
2. Reference Information
3. Product Specifications
4. Disassembly and Reassembly
5. Troubleshooting
6. Alignment and Adjustment
7. Exploded View and Parts List
8. Electrical Parts List
9. Block Diagrams
10. PCB Diagrams
11. Wiring Diagram
12. Schematic Diagrams
© Samsung Electronics Co., Ltd. OCT. 1997 AC68-20378A

Samsung Electronics 1-1
1. Precautions
1. Be sure that all of the built-in protective devices are
replaced. Restore any missing protective shields.
2. When reinstalling the chassis and its assemblies, be
sure to restore all pretective devices, including :
control knobs and compartment covers.
3. Make sure that there are no cabinet openings
through which people--particularly children
--might insert fingers and contact dangerous
voltages. Such openings include the spacing
between the picture tube and the cabinet mask,
excessively wide cabinet ventilation slots, and
improperly fitted back covers.
If the measured resistance is less than 1.0 megohm
or greater than 5.2 megohms, an abnormality exists
that must be corrected before the unit is returned
to the customer.
4. Leakage Current Hot Check (See Fig. 1) :
Warning : Do not use an isolation transformer
during this test. Use a leakage current tester or a
metering system that complies with American
National Standards Institute (ANSI C101.1,
Leakage Current for Appliances), and Underwriters
Laboratories (UL Publication UL1410, 59.7).
5. With the unit completely reassembled, plug the AC
line cord directly the power outlet. With the unit’s
AC switch first in the ON position and then OFF,
measure the current between a known erath
ground (metal water pipe, conduit, etc.) and all
exposed metal parts, including : antennas, handle
brackets, metal cabinets, screwheads and control
shafts. The current measured should not exceed
0.5 milliamp. Reverse the power-plug prongs in the
AC outlet and repeat the test.
6. X-ray Limits :
The picture tube is designed to prohibit X-ray
emissions. To ensure continued X-ray protection,
replace the picture tube only with one that is the
same type as the original.
Fig. 1-1 AC Leakage Test
7. Antenna Cold Check :
With the unit’s AC plug disconnected from the
AC source, connect an electrical jumper across the
two AC prongs. Connect one lead of the ohmmeter
to an AC prong.
Connect the other lead to the coaxial connector.
8. High Voltage Limit :
High voltage must be measured each time
servicing is done on the B+, horizontal deflection
or high voltage circuits.
Heed the high voltage limits. These include the
X-ray protection Specifications Label, and the
Product Safety and X-ray Warning Note on the
service data schematic.
9. Some semiconductor (“solid state”) devices are
easily damaged by static electricity.
Such components are called Electrostatically
Sensitive Devices (ESDs); examples include
integrated circuits and some field-effect transistors.
The following techniques will reduce the
occurrence of component damage caused by static
electricity.
10. Immediately before handling sny semiconductor
components or assemblies, drain the electrostatic
charge from your body by touching a known
earth ground. Alternatively, wear a discharging
Wrist-strap device. (Be sure to remove it prior to
applying power--this is an electric shock
precaution.)
Device
Under 
Test
(Reading should
not be above
0.5mA)
Leakage
Currant
Tester
Earth
Ground
Test all
exposed metal
surfaces
Also test with
plug reversed
(using AC adapter
plug as required)
2-Wire Cord

Precautions
1-2 Samsung Electronics
11. High voltage is maintained within specified limits
by close-tolerance, safety-related components and
adjustments. If the high voltage exceeds the
specified limits, check each of the special
components.
12. Design Alteration Warning :
Never alter or add to the mechanical or electrical
design of this unit. Example : Do not add
auxiliary audio or video connectors. Such
alterations might create a safety hazard. Also, any
design changes or additions will void the
manufacturer’s warranty.
13. Hot Chassis Warning :
Some TV receiver chassis are electrically
connected directly to one conductor of the AC
power cord. If an isolation transformer is not
used, these units may be safely serviced only if
the AC power plug is inserted so that the chassis
is connected to the ground side of the AC source.
To confirm that the AC power plug is inserted
correctly, do the following : Using an AC
voltmeter, measure the voltage between the
chassis and a known earth ground. If the reading
is greater than 1.0V, remove the AC power plug,
reverse its polarity and reinsert. Re-measure the
voltage between the chassis and ground.
14. Some TV chassis are designed to operate with 85
volts AC between chassis and ground, regardless
of the AC plug polarity. These units can be safely
serviced only if an isolation transformer inserted
between the receiver and the power source.
15. Never defeat any of the B+ voltage interlocks.
Do not apply AC power to the unit (or any of its
assemblies) unless all solid-state heat sinks are
correctly installed.
16. Always connect a test instrument’s ground lead to
the instrument chassis ground before connecting
the positive lead; always remove the instrument’s
ground lead last.
17. Observe the original lead dress, especially near
the following areas : Antenna wiring, sharp
edges, and especially the AC and high voltage
power supplies. Always inspect for pinched, out-
of-place, or frayed wiring. Do not change the
spacing between components and the printed
circuit board. Check the AC power cord for
damage. Make sure that leads and components
do not touch thermally hot parts.
18. Picture Tube Implosion Warning :
The picture tube in this receiver employs
“integral implosion” protection. To ensure
continued implosion protection, make sure that
the replacement picture tube is the same as the
original.
19. Do not remove, install or handle the picture tube
without first putting on shatterproof goggles
equipped with side shields. Never handle the
picture tube by its neck. Some “in-line” picture
tubes are equipped with a permanently attached
deflection yoke; do not try to remove such
“permanently attached” yokes from the picture
tube.
20. Product Safety Notice :
Some electrical and mechanical parts have special
safety-related characteristics which might not be
obvious from visual inspection. These safety
features and the protection they give might be
lost if the replacement component differs from the
original--even if the replacement is rated for
higher voltage, wattage, etc.
Components that are critical for safety are
indicated in the circuit diagram by shading,
( or ).
Use replacement components that have the same
ratings, especially for flame resistance and
dielectric strength specifications. A replacement
part that does not have the same safety
characteristics as the original might create shock,
fire or other hazards.

Samsung Electronics 2-1
2. Reference Information
2-1 Servicing Jigs and Special Tools
1. For this VCR chassis, the program switch and the
sensors (start/end/reel) are located on the main
PCB, not on the deck ass’y.
2. As long as the deck ass’y is connected to the main
PCB, all repairs are possible.
Important : In order to repair the main PCB
without the deck ass’y connected, the X-5 chassis
jig should be used.
3. To emulate the function of the sensors, connect a
jumper or solder land (two point) at service
option(W750) on the timer PCB. Be sure not to
operate function key within 6 seconds.
4. The X-5 chassis jig can be used for the following :
1) When repairing or confirming the operation of the
deck ass’y.
2) When replacing or repairing the components
located under the deck ass’y.
3) When repairing the function PCB.
5. The X-5 chassis jig can not be used for the
following :
1) Repairing defects in the video section.
2) Repairing defects in the audio section.
3) If the defect is related to tape speed.
Note :
1) Repair may not be possible if there is external
noise between the deck ass’y and main PCB.
2) If tape control signal is not connected to the jig,
the VCR must be operated in SP mode.
2-1-1 Servicing guide
X-5 Chassis Jig
E/Cable 1
E/Cable 2
Jig Item
68140-500-013
68140-300-105
68140-500-104
Part No.
Connects the deck ass’y to the main PCB connecting cable.
Use for ASS’Y SMPS (CN01) ↔ASS’Y MAIN (CN101) connecting cable.
Use for ASS’Y TIMER (CN703, CN704)↔ASS’Y JOINT (CN8J01, CN8J02)
Use
2-1-2 Servicing Jig
X-5 Chassis Jig E/Cable 1 E/Cable 2

Reference Information
2-2 Samsung Electronics
2-1-4 How to Connect X-5 chassis jig
4. Insert wafers of drum motor, capstan motor and
loading motor on X-5 chassis jig into each of the
connectors of deck ass’y, and then secure with
three screws.
5. Solder the 3 leads of the jig cable to “CN608”
on the main PCB.
6. Apply power to the function PCB.
7. Insert a test tape into the housing ass’y.
8. Simultaneously touch the start and end sensor
LEDs on the PCB, so that the tape loads
automatically. After the tape is loaded, all of the
function buttons on the function PCB can be
used.
9. If the test tape is ejected while the jig is in use,
attempt to re-load the tape by simultaneously
touching the start and end sensor LEDs. If the tape
still does not load, turn power off in order to reset.
Note : After completing repairs, turn power off in order to reset.
1. Unplug the power cord from AC outlet.
2. Remove the deck ass’y from main PCB (See Page
4-5 of service manual).
3. To emulate the function of the sensors, place a
jumper or solder land (two point) at service
option(W750) on the timer PCB. Be sure not to
operate function key within 6 seconds.
(see diagram below).
Function-Timer (Conductor side)

Reference Information
Samsung Electronics 2-3
CONNECTS TO THE ASS'Y MAIN CN604.
CONNECTS TO THE ASS'Y MAIN CN608.
CONNECTS TO THE 
ASS'Y MAIN CN603.
CONNECTS TO THE ASS'Y MAIN CN602.
CONNECTS TO THE DRUM MOTOR 
CONNECTOR OF ASS'Y FULL DECK.
CONNECTS TO THE CAPSTAN MOTOR 
CONNECTOR OF ASS'Y FULL DECK.
CONNECTS TO THE LOADING MOTOR CONNECTOR OF ASS'Y FULL DECK.
ASS'Y FULL DECK
ASS'Y MAIN
1 SCREW (1-3X10)
2 SCREWS (2-3X10)
CN604
CN603
CN608
CN602
How to Connect X-5 chassis jig

Reference Information
2-4 Samsung Electronics
How to Connect E/Cable 1
How to Connect E/Cable 2
ASS’Y MAIN CN101
CN1
ASS’Y SMPS
E/CABLE 1
E/CABLE 2
ASS’Y TIMER
ASS’Y JOINT
CN8J01
CN8J02
CN703
CN704

Samsung Electronics 3-1
3. Product Specifications
Design and specifications are subject to change without notice.
Operation Description
Recording system Rotary head azimuth recording, luminance signal FM recording system
Crominance signal down converted phase shift recording system
(NTSC, PAL, PAL-M)
Chrominance signal down converted direct recording system (MESECAM)
Chrominance signal 1/4 frequency countdown direct recording system
(SECAM)
Color system NTSC3.58, NTSC4.43, PAL, PAL-M, PAL-N, SECAM
Tuning system B/G, D/K, I, M, N
RF out Splitter type (without RF converter)
Tape recording/playback NTSC, PAL, PAL-M, SECAM, MESECAM
Tape speed NTSC 33.35mm/sec (standard recording)
PAL-M 16.375mm/sec (when playing the double speed recording tape)
11.12mm/sec (three times recording)
PAL 23.39mm/sec (standard recording)
MESECAM 11.69mm/sec (double speed recording)
SECAM
Tape format VHS tyep video tape, S-VHS type video type (playback only)
Recording time Maximum 8 hours (with a T-160 tape)
Rewinding time within 3 minutes (High speed rewinding, T-120 or E-180 tpae)
Video input 1.0Vp-p (Unbalanced) 75 Ω
Video output 1.0Vp-p (Unbalanced) 75 Ω
Video S/N Above 43dB (standard recording)
Resolution Above 220 (standard recording NTSC), 240 (standard recording PAL)
Audio input -8dBm
Audio output -6dBm (Hi-Fi), -7dBm (Mono)
Audio S/N Above 39dB (Mono), 68dB (Hi-Fi)
Audio frequency 20Hz-20KHz (Hi-Fi standard recording)
characteristics 100Hz-10KHz (standard recording NTSC)
100Hz-8KHz (standard recording PAL), 100Hz-8KHz (SLP, LP)
Rated voltage 100V~240V AC
Rated frequency 50/60Hz
Power consumption ARP. 26watts on recording; 8 watts off
Working ambient temperature 41°F-104°F (5°C-40°C)
Installation conditions Operation position : Horizontal, Relative humidity : Below 80%
Outside dimensions Width 17.8 inches X Length 13.0 inches X Height 3.4 inches
Weight 13.2 lbs

Product Specifications
3-2 Samsung Electronics
MEMO

Samsung Electronics 4-1
4. Disassembly and Reassembly
4-1 Cabinet Assembly
Note : Disassemble in the order shown.
Reassemble in reverse order.
4-1-1 Panel-Side L/R and Cabinet Top removal
"B"
"A"
´REMOVE 2 SCREWS.
(BH;5-4X16-BLOCK)
ˇRELEASE 2 HOOKS.
ŒREMOVE 1 SCREW.
(BH;5-4X16-BLOCK)
"C"
¨REMOVE THE PANEL-SIDE(L) IN THE DIRECTION OF ARROW "A".
ˆREMOVE 2 SCREWS.
(BH;5-4X16-BLOCK)
ØRELEASE 2 HOOKS.
∏REMOVE THE PANEL-SIDE(R) IN THE DIRECTION OF ARROW "B".
”LIFT UP THE CABINET-TOP 
IN THE DIRECTION OF ARROW "C".
Fig. 4-1 Cabinet Top removal

Disassembly and Reassembly
4-2 Samsung Electronics
4-1-2 Bottom cover removal
Fig. 4-2 Bottom Cover removal
"A"
"A"
"B"
ŒREMOVE 3 SCREWS.
(BH;3-3X12-YELLOW)
´REMOVE THE DECORATION-LEG IN THE
DIRECTION OF ARROW "A".
ˇRELEASE 2 TABS.
¨RELEASE 2 TABS.
ˆLIFT UP THE COVER-BOTTOM
IN THE DIRECTION OF ARROW "B".

Disassembly and Reassembly
Samsung Electronics 4-3
4-1-3 Ass’y Front Panel removal
(Bottom view)
ŒRELEASE 4 HOOKS.
´RELEASE 3 HOOKS.
(Top view)
Fig. 4-3 Ass’y Front Panel removal

Disassembly and Reassembly
4-4 Samsung Electronics
4-1-4 Ass’y Function removal
Note : Take extreme care not to damage the PCB when removing it.
Fig. 4-4 Ass’y Function-Timer removal
ŒDISCONNECT CN4303 FROM THE ASS'Y I/O.
´RELEASE 6 HOOKS.
"A"
ˇREMOVE THE ASS'Y FUNCTION IN THE DIRECTION
OF ARROW "A".

Disassembly and Reassembly
Samsung Electronics 4-5
4-1-5 Ass’y Full Deck removal
Fig. 4-5 Ass’y Full Deck removal
"A"
ŒREMOVE THE CONNECTOR-WAFER IN THE DIRECTION OF ARROW "A".
"B"
´REMOVE 2 SCREWS.
ˇREMOVE 2 SCREWS.
¨LIFT UP THE ASS'Y FULL DECK
IN THE DIRECTION OF ARROW "B".

Disassembly and Reassembly
4-6 Samsung Electronics
4-1-6 Ass’y SMPS removal
Fig. 4-6 Ass’y SMPS removal
ΠREMOVE 3 SCREWS.
´REMOVE THE ASS'Y SMPS
IN THE DIRECTION OF ARROW.
4-1-7 Ass’y Digital removal
Fig. 4-7 Ass’y Digital removal
Œ REMOVE HOLDER PCB. ´DISCONNECT CNA2 FROM ASS'Y I/O.
ˇDISCONNECT CNA1 FROM ASS'Y IF.
¨LIFT UP THE ASS'Y DIGITAL IN THE DIRECTION OF ARROW.

Disassembly and Reassembly
Samsung Electronics 4-7
4-1-8 Ass’y IF removal
Fig. 4-8 Ass’y IF removal
ŒREMOVE 2 SCREWS.
´RELEASE 4 TABS.
ˇLIFT UP THE ASS'Y IF IN THE DIRECTION OF ARROW.

Disassembly and Reassembly
4-8 Samsung Electronics
4-1-9 Ass’y Main removal
Fig. 4-9 Ass’y Main removal
ŒREMOVE 1 SCREW.
´RELEASE 3 TABS.
ˇLIFT UP THE ASS'Y MAIN IN THE DIRECTION 
OF ARROW.

Disassembly and Reassembly
Samsung Electronics 4-9
4-2 Circuit Board Locations
ASS'Y FUNCTION ASS'Y MAIN
ASS'Y SMPS
ASS'Y I/O
ASS'Y IF
ASS'Y DIGITAL
Fig. 4-10 Circuit Board Locations

Disassembly and Reassembly
4-10 Samsung Electronics
MEMO

Samsung Electronics 6-1
6. Alignment and Adjustment
Note : After replacing the ass’y full deck, the ass’y main, the cylinder ass’y and the micom(IC601), the remote
control ass’y can be used to adjust the “X-point (tracking center) adjustment” and “Head S/W point”
adjustment.
6-1 Reference
6-1-1 The type of remote control ass’y
The remote control ass’y of SV-4000W unit.
VCR
POWER EJECT
INDEX REC.SPEED CLK/COUNT PICTURE Q-PRO
ART INPUT
123
46
789
0CLR/RST
MENU
CH
R
E
W
P
L
A
Y
F
.
F
DISPLAY MONITOR A.DUB
REC P/STILL
INPUT
SYSTEM OUTPUT SYSTEM
A.TRK SLOW
REV
FWD
STOP
FINE
STROBE AUDIO
OK
"SPEED" BUTTON
(H'D S/W ADJ.)
5"5" BUTTON
(TRACKING
CENTER ADJ.)
"VCR POWER" 
BUTTON
(RESET)
"FINE" BUTTON
(TRK MAX./MIN.)
Fig. 6-1 Remote control ass’y of SV-4000W unit