Sony HCDV-4800 Service manual

HCD-V4800

SERVICE MANUAL

HCD-4800 is the tuner, deck, Video CD and amplifier section in LBT-V4800/V4800R.

* Dolby noise reduction manufactured under

license from Dolby Laboratories Licensing Corporation. “DOLBY” and the double-D symbol a are trademarks of Dolby Laboratories Licensing Corporation.

CD Section

Tape deck Section

E Model

Chinese Model

Model Name Using Similar Mechanism HCD-V3500 CD Mechanism Type Base Unit Name BU-5BD21AL Optical Pick-up Name Model Name Using Similar Mechanism HCD-V808 T ape Transport Mechanism T ype TCM-220WR2

CDM37L-5BD21AL

KSS-213D/Q-NP

SPECIFICA TIONS

– Continued on next page –

MICROFILM

MINI Hi-Fi COMPONENT SYSTEM

CAUTION

Use of controls or adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.

This appliance is classified as a CLASS 1 LASER product. The CLASS 1 LASER PRODUCT MARKING is located on the rear exterior.

Laser component in this product is capable of emitting radiation exceeding the limit for Class 1.

The following caution label is located inside the unit.

MODEL IDENTIFICA TION

– BACK PANEL –

PAR T No.

MODEL PAR T NO. Singapore 4-992-219-0π Malaysia, Thai 4-992-219-1π Chinese 4-992-219-2π Indonesia 4-992-219-3π

SAFETY -RELA TED COMPONENT W ARNING!!

COMPONENTS IDENTIFIED BY MARK ! OR DOTTED LINE WITH MARK ! ON THE SCHEMA TIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PAR TS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY .

– 2 –

T ABLE OF CONTENTS

SERVICING NOTES

1 . GENERAL

.................................................................. 4

2 . DISASSEMBL Y ......................................................... 7

3 . TEST MODE ............................................................. 15

4 . MECHANICAL ADJUSTMENTS ...................... 18

5 . ELECTRICAL ADJUSTMENTS

DECK Section ................................................................. 18

CD Section....................................................................... 21

VIDEO Section................................................................ 22

6 . DIAGRAMS

6-1. IC Pin Function Description ............................................ 23

6-2. Printed Wiring Board —BD Section— ........................... 33

6-3. Schematic Diagram —BD Section— .............................. 35

6-4. Printed Wiring Boards —CD MOT OR Section— .......... 37

6-5. Schematic Diagram —CD MOTOR Section—............... 39

6-6. Printed Wiring Boards —VIDEO Section—................... 42

6-7. Schematic Diagram —VIDEO Section— ....................... 45

6-8. Schematic Diagram —DECK Section—......................... 51

6-9. Printed Wiring Boards —DECK Section— .................... 55

6-10. Printed Wiring Boards

—MAIN/DECK/POWER SUPPLY Section— ............... 58

6-11. Schematic Diagram

—MAIN/POWER SUPPLY Section— ........................... 61

6-12. Schematic Diagram —PANEL Section— ....................... 68

6-13. Printed Wiring Boards —PANEL Section—................... 71

6-14. Schematic Diagram

—POWER AMP/KEY CONTROL Section—................ 74

6-15. Printed Wiring Boards

—POWER AMP/KEY CONTROL Section—................ 77

7 . EXPLODED VIEWS ............................................... 88

8 . ELECTRICAL P ARTS LIST ................................ 97

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostatic break-down because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body. During repair, pay attention to electrostatic break-down and also use the procedure in the printed matter which is included in the repair parts. The flexible board is easily damaged and should be handled with care.

NOTES ON LASER DIODE EMISSION CHECK

The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pick-up block. Therefore, when checking the laser diode emission, observe from more than 30 cm away from the objective lens.

LASER DIODE AND FOCUS SEARCH OPERATION CHECK

Carry out the “S curve check” in “CD section adjustment” and check that the S curve waveforms is output three times.

Notes on chip component replacement

• Never reuse a disconnected chip component.

• Notice that the minus side of a tantalum capacitor may be damaged by heat.

Flexible Circuit Board Repairing

• Keep the temperature of the soldering iron around 270 ˚C during repairing.

• Do not touch the soldering iron on the same conductor of the circuit board (within 3 times).

• Be careful not to apply force on the conductor when soldering or unsoldering.

– 3 –

SECTION 1

GENERAL

LOCA TION OF CONTROLS — Front Panel —

4321

@£ @¢

@∞

@§ @¶

@• @ª

#º

#¡ #™

#£ #¢ #∞ #§

1 POWER button 2 SPECTRUM ANALYZER button 3 DISPLAY/DEMO button 4 Remote control receiver

#¶

!¡

#• #ª

!™ !£

!¢ !∞ !§

!¶ !•

!ª @º

@¡ @™

5 Fluorescent indicator tube 6 EFFECT button and indicator 7 ENTER/NEXT button and indicator 8 TUNER MEMORY button 9 TUNING MODE button 0 TUNING – button !¡ TUNER/BAND button and indicator !™ TUNING + button !£ STEREO/MONO button !¢ FUNCTION button !∞ VOLUME control knob !§ SUPER WOOFER button and indicator !¶ SUPER W MODE button !• p button (deck B side) !ª ) button (deck B side) @º 0 button (deck B side) @¡ § EJECT button (deck B side) @™ 6 OPEN button @£ t /CLOCK SET button @¢ SLEEP button @∞ REC button @§ ) button (deck A side) @¶ p button (deck A side) @• 0 button (deck A side) @ª § EJECT button (deck A side) #º DIRECT PLAY DISC 1 to DISC 5 buttons #¡ ˆ RETURN button #™ PREV button #£ NEXT button #¢ Cassette holder (deck A side) #∞ CD disc tray #§ Cassette holder (deck B side) #¶ 0 button #• ≠ AMS ± jog dial knob #ª ) button

– 4 –

%¡

%™ %£

%¢

%∞

$¡$™$£

$º

%¶%§

%•

$º SOUND CONTROL WAVE button $¡ SOUND CONTROL SURROUND button $™ P FILE MEMORY button $£ GEQ CONTROL button $¢ GROOVE button and indicator $∞ GEQ cursor control

$¢

$∞ $§

$¶

$•

$ª

%º

^¡^º%ª

$§ ENTER button and indicator $¶ KEY CONTROL n button $• · button and indicator $ª p button %º REPEAT button %¡ MIC LEVEL control knob %™ ECHO LEVEL control knob %£ KARAOKE PON/MPX button %¢ KEY CONTROL ˜ button %∞ CD NON-STOP button and indicator %§ DJ MIX CD LOOP button %¶ DJ MIX CD FLASH button %• KEY CONTROL indicator %ª DISC SKIP button ^º EDIT button ^¡ P button and indicator

&∞ &§

&¶ &•

&ª *º

*¡

*™ *£

^™ ^£ ^¢ ^∞ ^§

*§

*∞

*¢

^¶

*¶

^• ^ª

&º &¡

&™

&£

&¢

^™ FILE 1/MOVIE/ROCK indicator ^£ FILE 2/GAME/POP indicator ^¢ FILE 3/NIGHT/JAZZ indicator ^∞ FILE 4/PARTY/DANCE indicator ^§ FILE 5/RELAX/SALSA indicator ^¶ P FILE/MENU 2/MENU 1 indicator ^• ª button and indicator (deck B side) ^ª · button and indicator (deck B side) &º r REC button and indicator &¡ CD SYNC button &™ H SPEED DUB button &£ PLAY MODE button &¢ 1/ALL DISCS button &∞ DAILY 1 button &§ DAILY 2 button &¶ MIC 1 jack &• MIC 2 jack &ª PHONES jack *º · button and indicator (deck A side) *¡ ª button and indicator (deck A side) *™ DIRECTION button *£ DOLBY NR button *¢ VCD indicator *∞ PBC indicator *§ AUTO PBC indicator *¶ P PAUSE button and indicator

– 5 –

— Rear Panel —

1 FM ANTENNA terminal 2 AM ANTENNA terminal 3 VOLTAGE SELECTOR (except Malaysia, Thai models) 4 PHONO IN pin jack 5 VIDEO (AUDIO) IN pin jack 6 VIDEO (AUDIO) OUT pin jack 7 SPEAKER output terminal 8 VIDEO OUT pin jack 9 S VIDEO OUT connector 0 SYSTEM SELECT switch (NTSC/AUTO/PAL select)

– 6 –

• This set can be disassembled in the order shown below.

)

SECTION 2

DISASSEMBL Y

CASE (Page 7)

Note: Follow the disassembly procedure in the numerical order given.

FRONT PANEL SECTION (Page 8)

MAIN SECTION (Page 9)

TAPE MECHANISM DECK SECTION (TCM-220WR2) (Page 10)

CD LID ASS’Y SECTION (Page 11)

MAIN BOARD (Page 8)

CD MECHANISM DECK SECTION (CDM37L-5BD21AL) (Page 9)

PANEL (A)/(B) SUB ASS’Y (Page 11)

CASE

BASE UNIT (BU-5BD21AL) (Page 12)

DISC TABLE (Page 12)

CAPSTAN MOTOR (M1) (Page 14)

CASSETTE LID ASS’Y (Page 10)

BD BOARD (Page 13)

OPTICAL PICK-UP (KSS-213D/Q-NP) (Page 13)

SLED MOTOR (M102), SPINDLE MOTOR (M101) (Page 13)

screw (case 3 TP2)

case

screw (case 3 TP2)

two screws (case 3 point

two screws (case 3 point)

– 7 –

seven screws (BVTT 3

FRONT P ANEL SECTION

)

front panel section

flat wire (11 core)

(CN206)

flat wire (21 core)

(CN205)

flat wire (17 core)

(CN102)

four screws

(BVTP 3 × 8)

MAIN BOARD

•

Installing the power cord for

the chinese model.

power transformer

power cord

ferrite core

wire clamp

connector (CN901)

power cord

back panel

fourteen screws (BVTP 3

flat wire (13 core (CN1)

MAIN board

IC201

flat wire (13 core) (CN202)

connector (CN106)

– 8 –

connector (CN203)

connector (CN101)

two screws (BVTP 3

MAIN SECTION

two screws (BVTP 3

flat wire (13 core)

connector (CN203)

(CN202)

main section

eight screws (BVTP 3

two screws (BVTP 3

CD MECHANISM DECK SECTION (CDM37L-5BD21AL)

five screws

CD mechanism deck section (CDM37A-5BD21AL)

(BVTP 3

flat wire (29 core) (CN101)

– 9 –

Open the clamp.

T APE MECHANSM DECK SECTION (TCM-220WR2)

)

three screws (BVTP 2.6

flat wire (21 core) (CN601)

flat wore (11 core) (CN1001)

three screws (BVTP 2.6

Remove the tape mechanism deck section (TCM-220WR2) to derection of the arrow

Open the cassette lids.

CASSETTE LID ASS’Y

two springs

cassette lid ass’y

Push the two buttons.

two brackets

two screws (BVTP 2.6

– 10 –

)

connector (CN612)

two claws

panel (B) sub ass’y

two claws

panel (A) sub ass’y

two claws

four screws (BVTP 2.6

CD LID ASS’Y SECTION

connector (CN671)

four screws (BVTP 2.6

CD lid ass’y

CD-B1 SW board

connector (CN661)

four screws (BVTP 2.6

P ANEL (A) / (B) SUB ASS’Y

connector (CN642)

– 11 –

BASE UNIT (BU-5BD21AL)

base unit (BU-5BD21AL)

DISC T ABLE

Note:

When the disc table is installed, adjust the positions of roller cam amd mark ( as shown in the figure, then set to the groove of disc table.

boss

screw (BVTP 3

bracket (BU)

screw (BVTP 3

yoke bracket

step screw

disc tabl

– 12 –

)

BD BOARD

two screws (PTPWH M2.6

two springs

screw

(BVTP 2.6

Removal four solders. limit switch

(S101)

two screws (PTPWH M2.6

optical pick-up section

two springs

flat wire (16 core) (CN102)

BD board

OPTICAL PICK-UP (KSS-213D/Q-NP), SLED MOTOR (M102), SPINDLE MOTOR (M101)

optical pick-up (KSS-213D/Q-NP)

spindle motor

sled shaft

(M101)

two screw (P2 × 3)

claw

– 13 –

sled motor (M102)

CAPST AN MOTOR (M1)

Removal the AUDIO board to direction of the arrow

four screws (BTP 2.6

connector (CN651)

Removal the capstan motor (M1) to direction of the arrow

Break the soldering of motor lead.

claw

two scres (BTP 2.6

Hang two belts.

– 14 –

SECTION 3

TEST MODE

MC COLD RESET

• The cold reset clears all data including preset data stored in the RAM to initial conditions. Execute this mode when returning the set to the customer.

Procedure:

1. Press three buttons GROOVE , ENTER/NEXT , and

DISC 1 simultaneously.

2. The fluorescent indicator tube becomes blank instantaneously,

and the set is reset.

CD DELIVERY MODE

• This mode moves the pick-up to the position durable to vibration. Use this mode when returning the set to the customer after repair.

Procedure:

1. Press POWER button to turn the set ON.

2. Press PLAY MODE button and POWER button simulta-

neously.

3. A message “LOCK” is displayed on the fluorescent indicator

tube, and the CD delivery mode is set.

MC HOT RESET

• This mode resets the set with the preset data kept stored in the memory. The hot reset mode functions same as if the power cord is plugged in and out.

Procedure:

1. Press three buttons GROOVE , ENTER/NEXT , and

DISC 2 simultaneously.

2. The fluorescent indicator tube becomes blank instantaneously,

and the set is reset.

SLED SERVO MODE

• This mode can run the CD sled motor freely. Use this mode, for instance, when cleaning the pick-up.

Procedure:

1. Select the function “CD”.

2. Press three buttons GROOVE , ENTER/NEXT , and

CD FLASH simultaneously.

3. The Sled Servo mode is selected, if “CD” is blanking on the

fluorescent indicator tube.

4. With the CD in stop status, press ) button in CD section to

move the pick-up to outside track, or 0 button to inside track.

5. To exit from this mode, perform as follows:

1) Move the pick-up to the most inside track.

2) Press three buttons in the same manner as step 2.

Note:

• Always move the pick-up to most inside track when exiting from this mode. Otherwise, a disc will not be unloaded.

• Do not run the sled motor excessively, otherwise the gear can be chipped.

CHANGE-OVER OF AM TUNER STEP BETWEEN 9 kHz AND 10 kHz

• A step of AM channels can be changed over between 9 kHz and 10 kHz.

Procedure:

1. Press POWER button to turn the set ON.

2. Select the function “TUNER”, and press TUNER/BAND

button to select the BAND “AM”.

3. Press POWER button to turn the set OFF.

4. Press ENTER/NEXT and POWER buttons simultaneously,

and the display of fluorescent indicator tube changes to “AM 9 k STEP” or “AM 10 k STEP”, and thus the channel step is changed over. Be sure not to change with carelessness.

LED AND FLUORESCENT INDICA TOR TUBE ALL LIT , KEY CHECK MODE

Procedure:

1. Press three buttons GROOVE , ENTER/NEXT , and

DISC 3 simultaneously.

2. LEDs and fluorescent indicator tube are all turned on.

Press DIRECTION button, and the key check mode is activated.

3. In the key check mode, the fluorescent indicator tube displays

“K 1 J0 V0”. Each time a button is pressed, “K”value increases. However, once a button is pressed, it is no longer taken into account. “J” value increases like 1, 2, 3 ... if rotating JOG dial knob in “+” direction, or it decreases like 0, 9, 8 ... if rotating in “–” direction. “V” value increases like 1, 2, 3 ... if rotating VOLUME knob in “+” direction, or it decreases like 0, 9, 8 ... if rotating in “–” direction.

4. To exit from this mode, press three buttons in the same manner

as step 1, or disconnect the power cord.

SELF-DIAGNOSIS

This model has the self-diagnosis function for the video and audio decoder sections. Immediately after the power on, the self-diagnosis function searches each operation of IC’s around the mechanism controller (IC701). The LED (D701) on the VIDEO board indicates their results.

LED (D701) INDICATION SYMPTOM

Light No error 1 time blinking (Repeatedly) External RAM (S-RAM) error

(IC751)

2 times blinking (Repeatedly) Video decoder section error

(IC201)

3 times blinking (Repeatedly) Video RAM (D-RAM) error

(IC251)

4 times blinking (Repeatedly) Audio decoder section error

(IC201)

[VIDEO BOARD] (SIDE-A)

IC701

D701

IC771

– 15 –

IC201

IC901

AGING MODE

This mode can be used for operation check of CD section and tape deck section.

• If an error occurred: The aging operation stops.

• If no error occurs: The aging operation continues repeatedly.

1. Aging Mode in CD Section

1-1. Operating Method of Aging Mode

1. Set discs in DISC 1 and DISC 3 trays.

2. Select the function “CD”.

3. Press three buttons GROOVE , ENTER/NEXT , and DISC 5 simultaneously.

4. The aging mode is activated, if a roulette mark on the fluorescent indicator tube is blinking.

5. In the aging mode, the aging is executed in a sequence given in “1-2. Operation during Aging Mode”. The aging continues unless an alarm occurred.

6. To exit from the aging mode, press POWER button to turn the set OFF.

• If a button other than buttons In CD section is pressed during aging, the aging in the CD section is finished.

• T o execute aging to the tape deck section successively , press · button in the deck A. “AGING” is displayed on the fluorescent indicator tube. (For the aging in tape deck, see “2. Aging Mode in Tape Deck Section”.

1-2. Operation during aging Mode In the aging mode, the program is executed in the following sequence.

1. The disc tray turns to select a disc. (For a disc selection sequence, see Section 1-3.)

2. TOC of disc is read.

3. The pick-up accesses to the last track.

4. Steps 1 through 3 are repeated.

7. In the aging mode, the aging is executed in a sequence given in “2-2. Operation during Aging Mode”. The aging continues unless an alarm occurred.

8. To exit from the aging mode, press POWER button to turn the set OFF.

2-2. Operation during Aging Mode In the aging mode, the program is executed in the following sequence.

1. A tape on FWD side is played for one minute.

2. PAUSE STOP is made.

3. Recording is made for 3 minutes. (For the deck not having the record function, the play is executed. In this case, · LED does not light up.)

4. FF is executed up to the end of tape.

5. A tape is reversed, and the tape on REV side is played for one minute.

6. PAUSE STOP is made.

7. Recording is made for 3 minutes. (For the deck not having the record function, the play is executed. In this case, ª LED does not light up.)

8. FF is executed up to the end of tape.

9. Steps 1 through 8 are executed for the other deck.

10. Steps 1 through 9 are repeated unless an alarm occurred.

2-3. Deck Selection Sequence

• During the aging mode, decks are selected in the following sequence:

Deck A (FWD) → Deck A (REV)

↑↓

Deck B (REV) ← Deck B (FWD)

1-3. Disc Selection Sequence

• During the aging mode, discs are selected in the following sequence:

Disc 1 → Disc 3

↑↓

Disc 3 ← Disc 1

2. Aging Mode in Tape Deck Section

2-1. Operating Method of Aging Mode

1. Load a commercially available 10-minute tape into the decks A and B respectively. (If a 10-minute tape is not available, another tape may be used but a cycle time will be longer.)

2. Select the function “TAPE”.

3. Rewind tapes in advance by pressing 0 button respectively on decks A and B.

4. Press three buttons GROOVE , ENTER/NEXT , and DISC 5 simultaneously.

5. Press · button on deck A. (This button triggers the aging mode.)

6. The aging mode is activated if “AGING A” is displayed on the fluorescent indicator tube.

– 16 –

VIDEO CD COLOR BAR MODE

On this mode, the data of the color bar signal as a picture signal and the 1 kHz sine wave signal as a sound signal are output by the mechanism controller (IC701) for the video CD signal check. When measurement of the voltage and waveform on the VIDEO board, perform it in this mode. For reference, the color bar signal can be observed at J9001 (VIDEO OUT) and the sound signal can be observed at J101 (VIDEO (AUDIO) OUT) using an oscilloscope.

Procedure:

1. Turned power switch on.

2. Press the FUNCTION button to select the CD.

3. Connect the SL701 on the VIDEO board with solder.

4. After measuring, remove the soldering installed.

oscilloscope

E-F BALANCE MODE

Refer to the SECTION 6 ELECTRICAL ADJUSTMENTS page

21.

Procedure:

1. Turned power switch on.

2. Press the FUNCTION button to select the CD.

3. Connect the SL701 and SL703 on the VIDEO board with solder.

4. Press the · button in playback.

5. Every pressing the REPEAT button, the tracking servo and sledding servo are turned on or off.

6. When the servo is off, the counter on front panel will not be changed.

7. After measuring, remove the soldering installed.

set

Ω

J9001 (VIDEO OUT)

+ –

A = 0.9 to 1.1 Vp-p B = 0.678 to 0.75 Vp-p C = 0.214 to 0.328 Vp-p

Fig. 1 Video CD Color Bar Signal Output from J9001

(VIDEO OUT)

[VIDEO BOARD] (SIDE-B)

SL703

SL702

SL701

IC751

IC251

– 17 –

SECTION 4

MECHANICAL ADJUSTMENTS

SECTION 5

ELECTRICAL ADJUSTMENTS

PRECAUTION

1. Clean the following parts with a denatured-alcohol-moistened swab:

record/playback head pinch roller erase head rubber belts capstan idlers

2. Demagnetize the record/playback head with a head demagnetizer.

3. Do not use a magnetized screwdriver for the adjustments.

4. After the adjustments, apply suitable locking compound to the parts adjusted.

5. The adjustments should be performed with the rated power supply voltage unless otherwise noted.

• T orque Measur ement

Mode Torque Meter Meter Reading

Forward CQ-102C

Forward Back Tension (0.026 – 0.082 oz•inch)

Reverse CQ-102RC

Reverse Back Tension (0.026 – 0.082 oz•inch)

FF, REW CQ-201B

CQ-102C

CQ-102RC

36 to 61g•cm

(0.50 – 0.84 oz•inch)

2 to 6g•cm

36 to 61g•cm

(0.50 – 0.84 oz•inch)

2 to 6g•cm

61 to 143g•cm

(0.85 – 1.98 oz•inch)

DECK SECTION

0 dB=0.775 V

1. Demagnetize the record/playback head with a head demagnetizer. (Do not bring the head demagnetizer close to the erase head.)

2. Do not use a magnetized screwdriver for the adjustments.

3. After the adjustments, apply suitable locking compound to the parts adjust.

4. The adjustments should be performed with the rated power supply voltage unless otherwise noted.

5. The adjustments should be performed in the order given in this service manual. (As a general rule, playback circuit adjustment should be completed before performing recording circuit adjustment.)

6. The adjustments should be performed for both L-CH and R-ch.

7. Switches and controls should be set as follows unless otherwise specified.

8. Set to test mode. (Press key switch same time

GROOVE ENTER/NEXT and DISC 4 buttons.)

T o exit from the test mode, press the POWER button.

• T est T ape

Tape Signal Used for

P-4-A100 10 kHz, –10 dB Azimuth Adjustment

WS-48B 3 kHz, 0 dB Tape Speed Adjustment

P-4-L300 315 Hz, 0 dB Level Adjustment

• T ape T ension Measurement

Mode Tension Meter Meter Reading

Forward CQ-403A more than 100 g (3.53 oz) Reverse CQ-403R more than 100 g (3.53 oz)

Record/Playback Head Azimuth Adjustment

DECK A DECK B

Note: Perform this adjustments for both decks.

Procedure:

1. Mode: Playback (FWD)

test tape P-4-A100 (10 kHz, –10 dB)

set

MAIN board CN207 pin

(L-CH)

(R-CH)

MAIN board CN207

(GND)

level meter

+ –

2. Turn the adjustment screw and check output peaks. If the peaks do not match for L-CH and R-CH, turn the adjustment screw that outputs match within 1 dB of peak.

output level

within 1 dB

L-CH peak

– 18 –

Screw position

R-CH peak

L-CH peak

R-CH peak

Screw position

3. Mode: Playback (FWD)

(

)

test tape P-4-A100 (10 kHz, –10 dB)

in phase 45°90°135°180

MAIN board CN207

set

(R-CH)

waveform of oscilloscope

good

(L-CH)

pin 2 (GND)

wrong

oscilloscope

T ape Speed Adjustment DECK A

Note: Start the Tape Speed adjustment as below after setting to the test

mode. In the test mode, the tape speed is high during pressing the H SPEED DUB button.

Procedure:

1. Turn the power switch on.

2. Press the GROOVE button, ENTER/NEXT button and DISC 4 button simultaneously. T o exit from the test mode, press the POWER button.

Mode: Playback (FWD)

test tape WS-48B (3 kHz, 0 dB)

set

frequency counter

+ –

4. Repeat steps 1 to 3 in playback (REV) mode.

5. After the adjustments, apply suitable locking compound to the parts adjusted.

Adjustment Location: Playback Head (Deck A)

Record/Playback Head (Deck B)

revers

forward

MAIN board CN207 (pin

pin 1 :R-CH

: L-CH)

1. Insert the WS-48B into the deck A and the blank tape into the deck B.

2. Press the r REC button and · button on the deck B. Then the deck B is at recording mode.

3. Set the deck A to playback mode.

4. Keep pressing the H SPEED DUB button in playback mode. Then at high speed mode.

5. Adjust RV652 on the AUDIO board so that frequency counter reads 6,000 ± 90 Hz.

6. Take off the H SPEED DUB button. Then at normal speed mode.

7. Adjust R V651 on the AUDIO board so that frequency counter reads 3,000 ± 90 Hz.

8. Frequency difference between deck A and deck B the beginning of the tape should be within ± 1.5 %.

Adjustment Location: AUDIO board (See page 20)

Sample Value of Wow and Flutter: 0.3% or less W.RMS

(WS-48B)

Playback level Adjustment DECK A DECK B

Procedure:

Mode: Playback (FWD)

test tape P-4-L300 (315 Hz, 0 dB)

set

MAIN board CN207 (pin

(pin

level meter

: L-CH)

: R-CH)

+ –

Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301 (L-CH) and RV401 (R-CH) so that adjustment within adjustment level as follows.

Adjustment Level:

CN207 PB level: 301.5 to 338.3 mV (– 8.2 to – 7.2 dB) level difference between the channels: within ± 0.5 dB

Adjustment Location: AUDIO board (See page 20)

– 19 –

Record bias Current Adjustment DECK B

Procedure:

1. Mode: Record

pin 6 (L-CH) of IC1501 on the MAIN board.

#¶

(R-CH) of IC1501 on the MAIN board.

1) 315 Hz

2) 10 kHz

AF OSC

attenuator

pin 2 (GND) of CN207 on the MAIN board.



50 mV (–23.8 dB)

 

600

Ω

set

2. Mode: Playback

recorded portion

level meter

blank tape CS-123

Adjustment and Connection Location:

[AUDIO BOARD] (Conductor Side)

RECORD

BAIS



RV301

® ®

RV401

PB LEVEL

– DECK B –

RV441RV341



(NORMAL)

LEVEL

TAPE SPEED

RV651

– DECK A –

(HIGH) RV652



RV311

  

RV411





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3 1

+ –

: L-CH) : R-CH)

set

MAIN board CN207 (pin

(pin

Confirm playback the signal recorded in step 1 become adjustable limits as follows. If these levels do not adjustable limits, adjustment the RV341 (LCH) and RV441 (R-CH) on the AUDIO board to repeat steps 1 and 2. Adjustable limits: Playback output of 315 Hz to playback out-

put of 10 kHz: ±0.5 dB

Adjustment Location: AUDIO board

Record Level Adjustment DECK B

Procedure:

1. Mode: Record

(L-CH) of IC1501 on the MAIN board.

#¶

(R-CH) of IC1501 on the MAIN board.

AF OSC

315 Hz, 50 mV (–23.8 dB)

Ω

attenuator

(GND) of CN207 on the MAIN board.

600

blank tape CS-123

set

[MAIN BOARD] (Component Side)

IC201

IC301

RV1501

21 1

IC1501

CN207

RECORD LEVEL

22 42

RV1551

CN205

2. Mode: Playback

recorded portion

set

MAIN board CN207 (pin

(pin

level meter

: L-CH)

: R-CH)

+ –

Confirm playback the signal recorded in step 1 become adjustable limits as follows. If these levels do not adjustable limits, adjustment the R V1501 (LCH) and RV1551 (R-CH) on the MAIN board to repeat steps 1 and 2.

Adjustable limits:

CN207 PB level: 47.3 to 53.1 mV (–24.3 to –23.3 dB)

Adjustment Location: MAIN board

– 20 –

CD SECTION

+ –

BD board

TP (TE)

TP (VC)

oscilloscope

(DC range)

Notes:

1. CD block basically constructed to operate without adjustment. Therefore, check each item in order given.

2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise indicated.

3. Use the oscilloscope with more than 10 MΩ impedance.

4. Clean an object lens by an applicator with neutral detergent when the signal level is low than specified value with the following checks.

S-Curve Check

Connection:

RF signal waveform

VOLT/DIV : 200 mV TIME/DIV: 500 ns (with the 10: 1 probe in use)

level: 1.3 Vp-p

+0.25 –0.20

When observing the eye pattern, set the oscilloscope for AC range and raise vertical sensitivity.

oscilloscope

BD board

TP (FE)

TP (VC)

+ –

Procedure:

1. Connect the oscilloscope to TP (FE) and TP (VC) on BD board.

2. Connect the TP (FEI) and TP (VC) with lead wire.

3. Turned power switch on.

4. Put disc (YEDS-18) in and turned power switch on again and

actuate the focus search.

5. Confirm that the oscilloscope waveform (S-curve) is symmetri-

cal between A and B. And confirm peak to peak level within

3.0 ± 1.0 Vp-p.

S-curve waveform

symmetry

within 3.0 ± 1.0 Vp-p

6. After check, remove the lead wire connected in step 2.

Note: • Try to measure several times to make sure that the ratio of A : B

or B : A is more than 10 : 7.

• T ake sweep time as long as possible and light up the brightness to obtain best waveform.

E-F Balance (T raverse) Check

Connection:

Procedure:

1. Connect the oscilloscope to TP (TE) and TP (VC) on BD board.

2. Turned power switch on.

3. Connect the SL702 and SL703 on the VIDEO board with solder.

4. Put disc (YEDS-18) in and press the · button, and play the number five track.

5. Press the REPEAT button. (The tracking servo and the sledding servo are turned off.)

6. Confirm that the level B of the oscilloscope’s waveform and the A (DC voltage) of the center of the traverse waveform. Confirm the following: A/B × 100 = less than ±22 %

T raverse waveform

Center of the waveform

0 V

A (DC voltage)

RF Level Check

Connection:

oscilloscope

(AC range)

BD board

TP (RF) TP (VC)

+ –

Procedure:

1. Connect the oscilloscope to TP (RF) and TP (VC) on BD board.

2. Turned power switch on. (stop mode)

3. Put disc (YEDS-18) in and press the · button.

4. Confirm that the oscilloscope waveform is clear and check RF signal level is correct or not.

Note: Clear RF signal waveform means that the shape “≈” can be clearly

distinguished at the center of the waveform.

level: 1.3 ± 0.6 Vp-p

7. Press the REPEAT button. (The tracking servo and the sledding servo are turned on.) Confirm that the C (DC voltage) is almost equal to the A (DC voltage) is step 6.

T raverse waveform

0 V

T racking servo

Sled servo

OFF

T racking servo Sled servo ON

8. After check, remove the soldering installed in step 3.

– 21 –

C (DC voltage)

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