Panasonic SAHT-878-GC, SAHT-878-GCS Service manual

ORDER NO.MD0403133C3

DVD Home Theater Sound System

SA-HT878GC SA-HT878GCS

Colour

(S).......................Silver Type

Specifications

lGeneral Power Source:

Power consumption: Dimensions (W×H×D): Mass: 3.2 kg lAmplifier section

RMS Output Power: Dolby Digital Mode

lTotal RMS Dolby Digital mode Power:

At 1kHz and total harmonic of 10%

lFront: 55 W/ Channel (6Ω) lCenter: 160 W/ Channel (6Ω) lSurround: 55 W/ Channel (6Ω)

At 100Hz and total harmonic of 10%

lActive subwoofers: 220 W/ Channel (4Ω)

DIN Output Power: Dolby Digital Mode:

lTotal DIN Dolby Digital mode Power:

At 1kHz and total harmonic of 1%

lFront: 40 W/ Channel (6Ω) lCenter: 120 W/ Channel (6Ω)

C 110/127/220-230/240V, 50/60Hz 25 W 430×68×359.2 mm

600 W

430 W

lSurround: 40 W/ Channel (6Ω)

At 100Hz and total harmonic of 1%

lSubwoofer: 150 W/ Channel (4Ω)

PMPO output power:

lFM tuner section

Frequency Range: 87.5-108.0MHz

Sensitivity: 2.5µV (IHF) S/N 26dB 2.2µV Antenna Terminal: 75Ω (non balance)

lAM tuner section (AM/MW)

Frequency Range:

AM Sensitivity S/N 20dB at 999kHz:

Phone Jack:

Terminal: Stereo 3.5mm jack

Mic Jack:

Sensitivity: 0.7mV, 1.2kΩ Terminal: Mono, 6.3mm jack (2 systems)

lDisc section Discs played [8 cm or 12 cm]:

5000 W

(50kHz in step)

522-1629kHz (9kHz in step) 520-1630kHz (10kHz in step)

560µV/m

SA-HT878GC / SA-HT878GCS

(1) DVD-RAM (DVD-VR compatible, JPEG formatted discs) (2) DVD-Audio (3) DVD-Video (4) DVD-R (DVD-Video compatible) (5) CD-Audio (CD-DA) (6) Video CD (7) SVCD (Conforming to IEC62107) (8) CD-R/CD-RW (CD-DA, Video-CD, SVCD, MP3, WMA, JPEG

formatted discs)

(9) MP3/WMA

lMaximum number of recognizable audio and picture contents and groups:

4000 audio and picture contents and 400 groups

lCompatible compression rate:

MP3: between 32 kbps and 320 kbps WMA: between 48 kbps and 320 kbps

(10) JPEG

lExif Ver 2.1 JPEG Baseline files lPicture resolution: between 320 x 240 and 6144 x 4096

pixels (sub sampling is 4:2:2 or 4:2:0)

(11) HighMAT Level 2 (Audio and lmage)

Pick up:

Source of light beam:

Semiconductor Laser

Wavelength:

lCD: 785nm lDVD: 662nm

Audio output (DISC):

Number of channels:

5.1 ch (FL, FR, C, SL, SR, SW)

Audio performance (measured at LINE OUT terminal):

Frequency response:

DVD (linear audio):

4 Hz-22 kHz (48 kHz sampling) 4 Hz-44 kHz (96 kHz sampling)

DVD-Audio: 4 Hz-88 kHz (192 kHz

sampling)

CD-Audio:

4 Hz-20 kHz

S/N ratio:

CD-Audio: 95 dB

Dynamic range:

DVD (linear audio): 95 dB CD-Audio: 93 dB

Total harmonic distortion:

CD-Audio: 0.005 %

lVideo section

ideo system:

Signal system: PAL 625/50, PAL 525/60,

NTSC

Composite video output:

Output level: 1 Vp-p (75 Ω) Terminal: Pin jack (1 system)

S-video output:

output level: 1 Vp-p (75 Ω)

C output level: PAL; 0.3Vp-p (75 Ω)

NTSC; 0.286 Vp-p (75 Ω)

Terminal S terminal (1 system)

Component video output (480P/480I):

output level: 1 Vp-p (75 Ω)

PBoutput level: PRoutput level: Terminal:

0.7 Vp-p (75 Ω)

0.7 Vp-p (75 Ω) Pin jack (Y: green, PB: blue,

: red) (1 system)

Power consumption in standby mode:

approx 0.7W

Note:

1. Specifications are subject to change without notice. Mass and dimensions are approximate.

2. Total harmonic distortion is measured by the digital spectrum analyzer.

Solder:

This model uses lead free solder (PbF).

SA-HT878GC / SA-HT878GCS

CONTENTS

Page Page

1 Use of Active Subwoofer 4

1.1. Checking Player when Active Subwoofer is not used

2 Safety Precautions

2.1. GENERAL GUIDELINES

3 Prevention of Electro Static Discharge (ESD) to

Electrostatically Sensitive (ES) Devices 4 Before Repair and Adjustment (Using Active Subwoofer) 5 Protection Circuitry 6 Precaution of Laser Diode 7 About Lead Free Solder (PbF) 8 General Description

8.1. Operating instructions

8.2. Disc information

9 Accessories 10 Handling Precautions for Optical Pickup Unit

10.1. Cautions to Be Taken in Handling the Optical Pickup Unit

10.2. Cautions to Be Taken When Replacing the Optical Pickup

10.3. Grounding for electrostatic breakdown prevention

11 DISASSEMBLING THE CASING AND CHECKING P.C.B.S

11.1. Disassembly Procedure

11.2. Casing Parts and P.C.B. Positions

11.3. Top Cabinet

11.4. Tray (When taking out disc manually)

11.5. Front Panel

11.6. FL P.C.B.,Volume P.C.B. and Mic P.C.B.

11.7. Mechanism Unit

11.8. DVD Module P.C.B.

11.9. Rear panel

11.10. Main P.C.B.

11.11. Service Position

12 ASSEMBL ING AND DISASSEM BLING THE MECHANISM UNIT

12.1. Disassembly Procedure

12.2. Traverse Unit

12.3. Tray

12.4. Loading section

12.5. Tray Loading P.C.B.

12.6. Optical Pickup Unit

12.7. Traverse Motor and Spindle Motor

13 DVD-Optic al Pick-up Self-Diagnosis and Replacement

5 6 6 7 7 8

8 9

10 11

11 11

13 13 14 14 14 15 15 15 16 16 16

17 17 18 19 20 21 24

Procedure

13.1. Optical Pickup Breakdown Diagnosis

13.2. Service Mode Table 1

13.3. DVD Self Diagnostic Function-Error Code

13.4. Last Error Code saved during NO PLAY

13.5. Service mode table 2

13.6. Sales demonstration lock function

13.7. Handling After Completing Repairs

14 Self-Diagn osis Function

14.1. Automatic Displayed Error Codes

14.2. Memorized Error Codes

15 Service Precautions

15.1. Recovery after the DVD player is repaired

15.2. Firmware version-up of the DVD player

16 Adjustmen t Procedure

16.1. Service Tools and Equipment

16.2. Important points in adjustment

16.3. Storing and Handling Test Discs

16.4. Optical adjustment

17 Abbreviations 18 Voltage Chart

18.1. DVD Module P.C.B.

18.2. Main P.C.B.

18.3. Tray Loading P.C.B.

18.4. FL P.C.B.

18.5. Mic P.C.B.

19 Schematic Diagram Notes 20 Block Diagram 21 Schematic Diagram 22 Printed Circuit Board Diagram 23 Wiring Connection Diagram 24 Illustration of IC's, Transistors and Diodes 25 Terminal Function of ICs

25.1. IC2018 (C2CBHG000139): System control

26 Parts Location and Replacement Parts List

26.1. Loading Mechanism, Traverse Unit & Cabinet

26.2. Component Parts List

26.3. Packing Materials & Accessories Parts List

26.4. Packaging

26 27 27 28 29 31 31

32 32

33 33

34 34 34 35

36 38

38 40 42 42 42

43 45 51 59 63 65 66

68 71 80 81

SA-HT878GC / SA-HT878GCS

1 Use of Active Subwoofer

1.1. Checking Player when Active Subwoofer is not used

1. This unit uses the active subwoofer to supply the power of the component, and the active subwoofer should be connected to the component to check operational conditions of the component.

2. If the active subwoofer is not available due to repair of the unit, use the following equipment.

Jig product number: RFKZ0182 (110V, 127V, 220V, 230V-240V for overseas domestic use)

SA-HT878GC / SA-HT878GCS

2 Safety Precautions

2.1. GENERAL GUIDELINES

1. When servicing, observe the original lead dress. If a short circuit is found, replace all parts which have been overheated or damaged by the short circuit.

2. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers shields are properly installed.

3. After servicing, make the following leakage current checks to prevent the customer from being exposed to shock hazards.

2.1.1. LEAKAGE CURRENT COLD

CHECK

1. Unplug the AC cord and connect a jumper between the two prongs on the plug.

2. Measure the resistance value, with an ohmmeter, between the jumpered AC plug and each exposed metallic cabinet part on the equipment such as screwheads, connectors, control shafts, etc. When the exposed metallic part has a return path to thechassis, the reading should be between 1MΩand 5.2MΩ.

When the exposed metal does not have a return path to

the chassis, the reading must be

Figure 1

2.1.2. LEAKAGE CURRENT HOT CHECK (See Figure 1 .)

1. Plug the AC cord directly into the AC outlet. Do not use an

isolation transformer for this check.

2. Connect a 1.5kΩ, 10 watts resistor, in parallel with a 0.15µF

capacitors, between each exposed metallic part on the set and a good earth ground such as a water pipe, as shown in Figure 1 .

3. Use an AC voltmeter, with 1000 ohms/volt or more

sensitivity, to measure the potential across the resistor.

4. Check each exposed metallic part, and measure the

voltage at each point.

5. Reverse the ACplug inthe AC outlet and repeat each of the

above measurements.

6. The potential at any point should not exceed 0.75 volts

RMS. A leakage current tester (Simpson Model 229 or equivalent) may be used to make the hot checks, leakage current must not exceed 1/2 milliamp. In case a measurement is outsideof the limits specified, there is a possibility of a shock hazard, and the equipment should be repaired and rechecked before it is returned to the customer.

3 Prevention of Electro Static Discharge (ESD) to

Electrostatically Sensitive (ES) Devices

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistorsand semiconductor caused by electro static discharge (ESD).

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available dischargingESD wrist strap, which should be removed for potential shock reasons prior to applying power to the unit under test.

2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.

4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static (ESD protected)" can generate electrical charge sufficient to damage ES devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.

6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparableconductive material).

7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed.

"chip" components. The following techniques should be used to help reduce the incidence of component damage

SA-HT878GC / SA-HT878GCS

Caution

Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.

8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD)sufficient to damage an ES device).

4 Before Repair and Adjustment (Using Active Subwoofer)

Disconnect AC power, discharge Power Supply Capacitors C546~C549 through a 10 Ω, 10 W resistor to ground. DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may destroy solid state devices. After repairs are completed, restore power gradually using a variac, to avoid overcurrent. Current consumption at AC 110/127/220-230/240 V, 50/60 Hz in NO SIGNAL mode should be ~ 1000 mA.

5 Protection Circuitry

The protection circuitry may have operated if either of the following conditions are noticed:

· No sound is heard when the power is turned on.

· Sound stops during a performance.

The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are “shorted”, or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used. If this occurs, follow the procedure outlines below:

1. Turn off the power.

2. Determine the cause of the problem and correct it.

3. Turn on the power once again after one minute.

Note:

When the protection circuitry functions, the unit will not operate unless the power is first turned off and then on again.

SA-HT878GC / SA-HT878GCS

6 Precaution of Laser Diode

CAUTION :

This product utilizes a laser. Invisible laser radiation is emitted from the optical pick up lens when the unit is turned on. Wavelength : 662nm(DVD)/785nm(VCD/CD) Maximum output radiation power from pick up : 100µW/VDE Laser radiation from pick up unit is safety level, but be sure the followings:

1. Do not disassemble the optical pick up unit, since radiation from exposed laser diode is dangerous.

2. Do not adjust the variable resistor on the pick up unit. It was already adjusted.

3. Do not look at the focus lens using optical instruments.

4. Recommend not to look at pick up lens for a long time.

7 About Lead Free Solder (PbF)

Distinction of PbF PCB: PCBs (manufactured) using lead free solder will have a Pbf stamp on the PCB.

Caution:

· Pb free solder has a higher melting point than standard solder; Typically the melting point is 50 - 70°F (30 - 40°C) higher.

Please use a high temperature soldering iron. In case of the soldering iron with temperature control,please set it to 700 ± 20°F (370 ± 10°C).

· Pb free solder will tend to splash when heated too high (about 1100°F/ 600°C).

When soldering or unsoldering, please completely remove all of the solder on the pins or solder area, and be sure to heat the soldering points with the Pb free solder until it melts enough.

SA-HT878GC / SA-HT878GCS

8 General Description

8.1. Operating instructions

[ /I]

SHIFT

SHIFTSHIFT

8.2. Disc information

SA-HT878GC / SA-HT878GCS

9 Accessories

Remote control

AM loop antenna

FM indoor antenna

Video Cable

AC power supply cord

System cable

Silver screw

Black screw

5 Speaker cables

(4m×3, 10m×2)

Clip

SA-HT878GC / SA-HT878GCS

10 Handling Precautions for Optical Pickup Unit

The laser diode in the optical pickup unit may brake down due to static electricity of clothes or human body. Use due caution to electrostatic breakdown when servicing and handling the laser diode.

10.1. Cautions to Be Taken in Handling the Optical Pickup Unit

The laser diode in the optical pickup unit may be damaged due to electrostatic discharge generating from clothes or human body. Use due caution to electrostatic discharge damage when servicing the laser diode.

1. Do not give a considerable shock to the optical pickup unit as it has an extremely high-precise structure.

2. To prevent the laser diode from the electrostatic discharge damage, the flexible cable of the optical pickup unit removed from the PCB should be short-circuited with a short pin or a clip.

3. The flexible cable may be cut off if an excessive force is applied to it. Use caution when handling the flexible cable.

4. The antistatic FPC is connected to the new optical pickup unit. After replacing the optical pickup unit and connecting the flexible cable, cut off the antistatic FPC.

10.2. Cautions to Be Taken When Replacing the Optical Pickup

The flexible cable of the optical pickup unit which was supplied as a component is equipped with a short clip to prevent the laser diode from being damaged due to electrostatic discharge. Remove the short clip before connecting the flexible cableand make sure that the short land is open. (If the flexible cable is short-circuited, remove the solder.)

10.3. Grounding for electrostatic breakdown prevention

Some devices such as the DVD player use the optical pickup (laser diode) and the optical pickup will be damaged by static electricity in the working environment. Proceed servicing works under the working environment where grounding works is completed.

10.3.1. Worktable grounding

1. Put a conductive material (sheet) or iron sheet on the area where the optical pickup is placed, and ground the sheet.

SA-HT878GC / SA-HT878GCS

10.3.2. Human body grounding

1. Use the anti-static wrist strap to discharge the static electricity form your body.

SA-HT878GC / SA-HT878GCS

11 DISASSEMBLING THE CASING AND CHECKING P.C.B.S

11.1. Disassembly Procedure

11.2. Casing Parts and P.C.B. Positions

SA-HT878GC / SA-HT878GCS

11.3. Top Cabinet

1. Unscrew the screws.

11.4. Tray (When taking out disc manually)

1. Separates the gear for drawing out tray from the

mechanism unit. It inserts a screwdriver in the gear. (The gear jig)

2. Insert the gear jig into the tray open/ close hole.

3. Turn the gear jig counterclockwise to open the tray.

11.5. Front Panel

1. Remove the tray top from the tray section.

2. Remove the connectors.

3. Release the tabs.

11.6. FL P.C.B.,Volume P.C.B. and Mic P.C.B.

SA-HT878GC / SA-HT878GCS

11.7. Mechanism Unit

1. Turn the gear jig clockwise to close the tray, turn until the gear jig not to turn.

2. Unscrew the screws.

3. Remove the connectors.

4. Pull out the mechanism unit vertically.

1. Remove the volume knob.

2. Unscrew the screws.

3. Remove the front angle.

4. Unscrew the screws.

11.8. DVD Module P.C.B.

1. Unscrew the screws.

2. Remove the connectors.

SA-HT878GC / SA-HT878GCS

11.9. Rear panel

1. Unscrew the screws.

2. Release the tabs.

11.10. Main P.C.B.

1. Unscrew the screws.

11.11.2. Servici ng position of the Main P.C.B.

11.11. Service Position

11.11.1. Servici ng position of the DVD Module P.C.B.

SA-HT878GC / SA-HT878GCS

12 ASSEMBLING AND

DISASSEMBLING THE MECHANISM UNIT

12.1. Disassembly Procedure

12.2. Traverse Unit

1. Slide the lever (A) in the arrow direction (to the opposite side) till it stops.

2. Slide the lever (A) further by bending the tab at the right side of the lever A in the right direction. (The right groove opens and the boss becomes seen.)

3. Open the lever (B) to left. (The 2 grooves at the left side open.)

4. Remove the traverse unit

SA-HT878GC / SA-HT878GCS

12.3. Tray

1. Slide the guide tray unit while pressing the stopper in the arrow direction, and remove the guide tray unit.

2. Raise the loading unit.

3. Slide the lever in the arrow direction till it stops and pull the tray out.

5. Remove the drive arm concave phase from the tray slider and tray.

1. Insert a part of the tray into the unit sliding over the

groove on the mechanical chassis unit.

2. Insert the tray to the point before the tab of the

mechanical chassis unit.

4. Spread the tabs at the both sides and pull the tray out. (The tray slides a little forward and stops.)

SA-HT878GC / SA-HT878GCS

3. Hook the drive arm concave phase over the tray and the tray slider.

4. Press in the tray.

5. Make sure that the tray and the drive arm move smoothly.

2. Hook the lock lever spring on the lock lever projection part temporarily.

3. Unlock the tab and remove the lock lever.

12.4. Loading section

1. Spread the tabs at the both sides and push out the drive arm shaft.

4. Remove the belt.

5. Unlock the tab and remove the pulley.

6. Remove the relay gear.

SA-HT878GC / SA-HT878GCS

7. Turn the change lever in the arrow direction till it stops.

8. Hook the change lever spring on the change lever project part temporarily.

9. Pull the lever (B) in the bottom side toyour side and remove the change lever.

13. Remove the drive rack, the sub rack and the drive gear.

12.5. Tray Loading P.C.B.

1. Unscrew the screws

10. Unscrew the screws.

11. Unlock the tabs and remove the guide piece (L).

12. Unlock the tabs and remove the guide piece (R).

SA-HT878GC / SA-HT878GCS

12.6. Optical Pickup Unit

12.6.1. Cautions to Be Taken in Handling the Optical Pickup Unit

1. Do not give a considerable shock to the optical pickup unit as it has an extremely high-precise structure.

2. To prevent the laser diode from the electrostatic discharge damage, the flexible cable of the optical pickup unit removed from the PCB should be short-circuited with a short pin or a clip.

3. The flexible cable may be cut off if an excessive force is applied to it. Use caution when handling the flexible cable.

4. The antistatic FPC is connected to the new optical pickup unit. After replacing the optical pickup unit and connecting the flexible cable, cut off the antistatic FPC.

12.6.2. Cautions to Be Taken When Replacing the Optical Pickup

SA-HT878GC / SA-HT878GCS

12.6.3. Procedure for Disassembling the Optical Pickup Unit

1. Spread the tabs to push in the pin.

3. Remove the traverse deck.

2. Remove the pins.

4. Move the optical pickup unit in the arrow direction till it stops.

5. Unscrew the screws.

SA-HT878GC / SA-HT878GCS

6. Remove the drive rack.

7. Unscrew the screw

8. Slide the shaft in the arrow direction.

10. Remove the optical pickup unit.

9. Lift the optical pickup unit with the shaft.

11. Pull the shaft and the rubber out.

SA-HT878GC / SA-HT878GCS

1. Pass the intermediate FPC through the frame hole.

2. Align the guide section of the optical pickup unit withthe rail.

3. Install the shaft top to the holder.

2. Remove the cover while lifting the inner gear.

3. Remove the solders.

12.7. Traverse Motor and Spindle Motor

1. Unscrew the screws.

4. Remove the traverse motor.

5. Remove the solders.

6. Remove the screw lock as carefully as you can.

7. Unscrew the screws with torx screw driver (T6).

8. Remove the spindle motor.

SA-HT878GC / SA-HT878GCS

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