Samsung Electronics
1-1
1. Precautions
1. Be sure that all of the built-in protective
devices are replaced.
2. When reinstalling the chassis and its
assemblies, be sure to restore all protective
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.
4. Design Alteration Warning:
Never alter or add to the mechanical or
electrical design of the 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.
5. Leakage Current Hot Check (Figure 1-1):
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).
With the unit completely reassembled, plug
the AC line cord directly into a 120V AC
outlet. With the unit's AC switch first in the
ON position and then OFF, measure the
current between a known earth ground
(metal water pipe, etc.) and all exposed
metal parts. Examples: 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.
6. Insulation Resistance Cold Check:
(1) With the unit's AC plug disconnected
from the AC source, connect an electrical
jumper across the two AC prongs. (2) Set
the power switch to ON. (3) Measure the
resistance between the shorted AC plug and
any exposed metallic parts. Example:
Screwheads, antenna, control shafts or
handle brackets.
If any of the exposed metallic parts has a
return path to the chassis, the measured
resistance should be between 1 and 5.2
megohms. If there is no return path, the
measured resistance should be "infinite." If
the resistance is outside these limits, a shock
hazard might exist. See Figure 1-2
1-1 Safety Precautions
Follow these safety, servicing and ESD precautions to prevent damage and protect against potential hazards
such as electrical shock and X-rays.
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
Fig. 1-1 AC Leakage Test
Antenna
Terminal
Exposed
Metal Part
ohm
Ohmmeter
Fig. 1-2 Insulation Resistance Test
Summary of Contents for DV4700V
Page 21: ...Samsung Electronics 5 2 5 1 Adjustment Point Location Alignment and Adjustment ...
Page 150: ...Samsung Electronics 8 1 8 Block Diagram ...
Page 151: ...Samsung Electronics 9 1 9 PCB Diagram 9 1 Front Top DV7720KV ...
Page 152: ...Samsung Electronics 9 2 PCB Diagram 9 2 Front Top DV4720KV ...
Page 153: ...Samsung Electronics 9 3 PCB Diagram 9 3 Video cd 9 4 1 Top view 9 4 2 Bottom view ...
Page 154: ...Samsung Electronics 9 4 PCB Diagram 9 3 Main ...
Page 155: ...Samsung Electronics 9 5 PCB Diagram ...
Page 156: ...Samsung Electronics 9 6 PCB Diagram 9 5 Power ...
Page 157: ...Samsung Electronics 9 7 PCB Diagram 9 6 Deck ...
Page 158: ...Samsung Electronics 9 8 PCB Diagram 9 7 Deck 9 8 Deck ...
Page 159: ...Samsung Electronics 10 1 10 Wiring Diagram Fig 10 1 Wiring Diagram DV7720KV DV4720V ...
Page 160: ...Samsung Electronics 10 2 Wiring Diagrams Fig 10 2 Wiring Diagram DV7700KV DV4700V ...
Page 161: ...Samsung Electronics 11 1 Schematic Diagrams 11 Schematic Diagram 11 1 Front ...
Page 162: ...Samsung Electronics 11 2 Schematic Diagrams 11 2 Main 1 4 Servo Section ...
Page 163: ...Samsung Electronics 11 3 Schematic Diagrams 11 3 Main 2 4 LD Video Section ...
Page 164: ...Samsung Electronics 11 4 Schematic Diagrams 11 4 Main 3 4 Audio Section ...
Page 165: ...Samsung Electronics 11 5 Schematic Diagrams 11 5 Main 4 4 Syscon Section ...
Page 166: ...Schematic Diagrams 11 Ð 6 Samsung Electronics 11 6 Video CD ...
Page 167: ...Samsung Electronics 11 7 Schematic Diagrams 11 8 Power DV 7620KV DV 7622KV ...