Samsung SP-A12G, SV-A12G Service Manual

VIDEO CASSETTE PLAYER VIDEO CASSETTE LINE RECORDER

SV-A12G/SP-A12G

SERVICE

Manual

VIDEO CASSETTE PLAYER/VIDEO CASSETTE LINE RECORDER

CONTENTS

PAL

For mechanical disassembly and adjustment, refer to the “Mechanical Manual” (DX7-R/DX-7RC, DX8-R/DX-8RC AC68-20316A).

1. Precautions

2. Reference Information

3. Product Specifications

4. Disassembly and Reassembly

5. Alignment and Adjustment

6. Exploded View and Parts List

7. Electrical Parts List

8. Block Diagrams

9. PCB Diagrams

10. Wiring Diagram

11. Schematic Diagrams

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 unitÕs 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 unitÕs 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 (Òsolid stateÓ) 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 manufacturerÕs 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 instrumentÕs ground lead to the instrument chassis ground before connecting the positive lead; always remove the instrumentÕs 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, outof-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 Òintegral implosionÓ 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 Òin-lineÓ picture tubes are equipped with a permanently attached deflection yoke; do not try to remove such Òpermanently attachedÓ 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 VCP chassis, the program switch and the sensors (start/end/reel) are located on the main PCB, not on the deck assÕy.

2. As long as the deck assÕy is connected to the main PCB, all repairs are possible. Important : In order to repair the main PCB without the deck assÕy connected, the X-5 chassis jig should be used.

3. To emulate the function of the sensors, plug the power cord to outlet with pressing SW711 on the function PCB.

4. The X-5 chassis jig can be used for the following :

1) When repairing or confirming the operation of the deck assÕy.

2) When replacing or repairing the components located under the deck assÕy.

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 : Accurate repair may not be possible due to

external noise between the deck assÕy and main PCB.

2-1-1 Servicing guide

X-5 Chassis Jig

Jig Item

68140-500-013

Part No.

Connects the deck ass’y to the main PCB connecting cable.

Use

2-1-2 Servicing Jig

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 assÕy, and then secure with three screws.

5. Solder the 3 leads of the jig cable to ÒSERVICE OPTIONÓ on the main PCB.

6. Apply power to the function PCB.

7. Insert a test tape into the housing assÕy.

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.

Note : After completing repairs, unplug and plug the power cord in order to reset.

1. Unplug the power cord from AC outlet.

2. Remove the deck assÕy from main PCB (See Page 4-4 of service manual).

3. To emulate the function of the sensors, plug the power cord to outlet with pressing SW711 on the function PCB (See diagram below).

The location of SVC OPTION(SW711) is same on the function PCB regardless of model.

Function (Component side)

Reference Information

Samsung Electronics 2-3

CONNECTS TO THE MAIN PCB CN604.

CONNECTS TO THE MAIN PCB SVC OPTION.

CONNECTS TO THE MAIN PCB CN606.

CONNECTS TO THE MAIN PCB CN601.

CONNECTS TO THE DRUM MOTOR CONNECTOR OF DECK ASS'Y.

CONNECTS TO THE CAPSTAN MOTOR CONNECTOR OF DECK ASS'Y.

CONNECTS TO THE LOADING MOTOR CONNECTOR OF DECK ASS'Y.

DECK ASS'Y

MAIN BOARD

1 SCREW (1-3X10)

2 SCREWS (2-3X10)

CN604

CN606

SVC OPTION

CN601

How to Connect X-5 chassis jig

Reference Information

2-4 Samsung Electronics

2-2 IC Blocks

2-2-1 IC601 (KS88C8016)

Reference Information

Samsung Electronics 2-5

2-2-2 IC301 (SS11511M)

Reference Information

2-6 Samsung Electronics

2-2-3 IC302 (LA7411)

Reference Information

Samsung Electronics 2-7

2-2-4 IC303 (SS23377M)

Reference Information

2-8 Samsung Electronics

MEMO

Samsung Electronics 3-1

3. Product Specifications and Comparison Chart

3-1 Product Specifications

Design and specifications are subject to change without notice.

Operation Description

Format VHS PAL standard Video Recording System 2 Rotary Heads, Helical Scanning System

Luminance : FM azimuth recording

Color : Down converted subcarrier phase shifted Television System CCIR Standard G, K Color System PAL, MESECAM, NT 4.43, NT PB (NT 3.58 REC) Tape Width 12.65 mm (1/2 inch) Tape Speed SP : (PAL) 23.39 mm/sec, (NTSC) 33.35 mm/sec Record/Playback Time SP : 4 hours (E-240 Tape) F.F/REW Time 100 sec ~ 4 min with E-180 Heads Video : 2 Rotary Heads

Audio/Control : 1 stationary head

Erase : 1 full track erase head VIDEO Input 0.5 to 2.0 Vp-p : 75 ohm unbalanced

Output 1.0 Vp-p : 75 ohm unbalanced Signal-to-Noise Ratio Better than 43 dB (SP) Horizontal Resolution More than 240 lines (SP)

Audio Input Line : -8 dBm, 47 Kohm unbalanced

Output Line : -8 ± 3 dBm, 1.5 Kohm unbalanced Signal-to-Noise Ratio More than 39dB Frequency Response 100Hz ~ 8KHz(SP)

Output Channel Channels 30 ~ 39 (preset CH 36) Power Requirement AC 100 ~ 240V 50/60Hz, DC 12V (CAR BATTERY ONLY) Power Consumption Approx. 17 watts Operation Temperature 41°F-104°F (5°C-40°C) Operation Humidity 10%-75% Weight 4.0 Kg Dimensions (W x H x D) 360 x 92 x 309 mm

Product Specifications

3-2 Samsung Electronics

3-2 Comparison Chart

SV-A12G O SP-A12G X

MODEL

FUNCTION

LINE RECORD

REMARK

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 Top Cabinet removal

REMOVE 5 SCREWS

1. Remove 5 screws and slide the top cabinet to the rear to remove.

Fig. 4-1 Top Cabinet removal

Disassembly and Reassembly

4-2 Samsung Electronics

4-1-2 Bottom cover removal

REMOVE 1 SCREW (BH;1-3X12 YELLOW)

"A"

LIFT UP THE BOTTOM COVER IN THE DIRECTION ARROW "A"

1. Remove 1 screw.

2. Lift up the bottom cover toward arrow ÒAÓ.

Fig. 4-2 Bottom Cover Removal

Disassembly and Reassembly

Samsung Electronics 4-3

4-1-3 Ass’y Front Panel removal

(Bottom view)

RELEASE 4 TABS

RELEASE 3 TABS

1. Remove the knob-shuttle.

2. Release 4 hooks on the top side and 3 hooks on the bottom side and then, pull the assÕy front panel to remove.

(Top view)

Fig. 4-3 Ass’y Front Panel removal

Disassembly and Reassembly

4-4 Samsung Electronics

4-1-4 Ass’y Function removal

RELEASE 4 TABS

1. Release 5 hooks and remove the assÕy function.

Note : Take extreme care not to damage the PCB when removing it.

Fig. 4-4 Ass’y Function Removal

Disassembly and Reassembly

Samsung Electronics 4-5

4-1-5 Chassis Removal

REMOVE 2 SCREWS (BH;2-3X12 YELLOW)

ASS'Y FULL DECK

CONNECTOR BOARD ASS'Y

ASS'Y MAIN

FRAME

RELEASE 2 HOOKS

REMOVE 2 SCREWS (BH;2-3X12 YELLOW)

1. Remove 2 screws holding the frame.

2. Remove 2 screws holding the connector board assÕy.

3. Remove 2 screws holding the housing assÕy.

4. Remove 2 screws holding the assÕy full deck.

5. Release 2 hooks holding the assÕy main.

6. Lift the assÕy full deck up.

7. Lift the assÕy main up to remove.

Note : 1. When removing chassis, take extreme care not to damage the main PCB front.

2. When reinstalling the deck on the main PCB, take extreme care not to damage the sensor.

Fig. 4-5 Chassis Removal

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