JVC UX-T550 SERVICE MANUAL

SERVICE MANUAL

MICRO COMPONENT SYSTEM

UX-T550

Contents

Safety precautions Important for laser products Preventing static electricity Disassembly method Adjustment method

1-2 1-4 1-5 1-6 1-17

This service manual is printed on 100% recycled paper.

Flow of functional operation until TOC read

Maintenance of laser pickup Replacement of laser pickup Description of major ICs

Area Suffix

B ------------------------------- U.K.

E ----------- Continental Europe EN ------------ Northern Europe EV -------------- Eastern Europe

EE --------- Russian Federation

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No.20908

Jan. 2001

UX-T550

1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. Services should be performed by qualified personnel only.

2. Alterations of the design or circuitry of the product should not be made. Any design alterations of the product should not be made. Any design alterations or additions will void the manufacturer`s warranty and will further relieve the manufacture of responsibility for personal injury or property damage resulting therefrom.

3. Many electrical and mechanical parts in the products have special safety-related characteristics.

These characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in the Parts List of Service Manual. Electrical components having such features are identified by shading on the schematics and by ( ) on the Parts List in the Service Manual. The use of a substitute replacement which does not have the same safety characteristics as the recommended replacement parts shown in the Parts List of Service Manual may create shock, fire, or other hazards.

4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the like to be separated from live parts, high temperature parts, moving parts and/or sharp edges for the prevention of electric shock and fire hazard. When service is required, the original lead routing and dress should be observed, and it should be confirmed that they have been returned to normal, after re-assembling.

5. Leakage currnet check (Electrical shock hazard testing) After re-assembling the product, always perform an isolation check on the exposed metal parts of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control shafts, etc.) to be sure the product is safe to operate without danger of electrical shock. Do not use a line isolation transformer during this check.

Plug the AC line cord directly into the AC outlet. Using a "Leakage Current Tester", measure the leakage current from each exposed metal parts of the cabinet , particularly any exposed metal part having a return path to the chassis, to a known good earth ground. Any leakage current must not exceed 0.5mA AC (r.m.s.)

Alternate check method Plug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms per volt or more sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by a 0.15 F AC-type capacitor between an exposed metal part and a known good earth ground. Measure the AC voltage across the resistor with the AC voltmeter.

AC VOLTMETER (Having 1000 ohms/volts, or more sensitivity)

Move the resistor connection to eachexposed metal part, particularly any exposed metal part having a return path to the chassis, and meausre the AC voltage across the resistor. Now, reverse the plug in the AC outlet and repeat each measurement. voltage measured Any must not exceed 0.75 V AC (r.m.s.).

0.15 F AC TYPE

1500 10W

Place this probe on each exposed metal part.

This corresponds to 0.5 mA AC (r.m.s.).

Good earth ground

1. This equipment has been designed and manufactured to meet international safety standards.

2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.

3. Repairs must be made in accordance with the relevant safety standards.

4. It is essential that safety critical components are replaced by approved parts.

5. If mains voltage selector is provided, check setting for local voltage.

!

Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system.

1-2

(U.K only)

1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits.

2. Any unauthorised design alterations or additions will void the manufacturer's guarantee ; furthermore the manufacturer cannot accept responsibility for personal injury or property damage resulting therefrom.

3. Essential safety critical components are identified by ( ) on the Parts List and by shading on the schematics, and must never be replaced by parts other than those listed in the manual. Please note

however that many electrical and mechanical parts in the product have special safety related characteristics. These characteristics are often not evident from visual inspection. Parts other than specified by the manufacturer may not have the same safety characteristics as the recommended replacement parts shown in the Parts List of the Service Manual and may create shock, fire, or other hazards.

4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the like to be separated from live parts, high temperature parts, moving parts and/or sharp edges for the prevention of electric shock and fire hazard. When service is required, the original lead routing and dress should be observed, and it should be confirmed that they have been returned to normal, after re-assembling.

UX-T550

1. Service should be performed by qualified personnel only.

2. This equipment has been designed and manufactured to meet international safety standards.

3. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.

4. Repairs must be made in accordance with the relevant safety standards.

5. It is essential that safety critical components are replaced by approved parts.

6. If mains voltage selector is provided, check setting for local voltage.

!

Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system.

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Important for Laser Products

1.CLASS 1 LASER PRODUCT

2.DANGER : Invisible laser radiation when open and inter

lock failed or defeated. Avoid direct exposure to beam.

3.CAUTION : There are no serviceable parts inside the

Laser Unit. Do not disassemble the Laser Unit. Replace the complete Laser Unit if it malfunctions.

4.CAUTION : The compact disc player uses invisible laser

radiation and is equipped with safety switches which prevent emission of radiation when the drawer is open and the safety interlocks have failed or are de feated. It is dangerous to defeat the safety switches.

VARNING : Osynlig laserstrålning är denna del är öppnad

och spårren är urkopplad. Betrakta ej strålen.

VARO : Avattaessa ja suojalukitus ohitettaessa olet

alttiina näkymättömälle lasersäteilylle.Älä katso säteeseen.

5.CAUTION : If safety switches malfunction, the laser is able

to function.

6.CAUTION : Use of controls, adjustments or performance of

procedures other than those specified herein may result in hazardous radiation exposure.

!

Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check.

ADVARSEL : Usynlig laserstråling ved åbning , når

sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling.

ADVARSEL : Usynlig laserstråling ved åpning,når

sikkerhetsbryteren er avslott. unngå utsettelse for stråling.

REPRODUCTION AND POSITION OF LABELS

WARNING LABEL

CLASS 1 LASER PRODUCT

DANGER : Invisibie laser radiation when open and interlock or defeated. AVOID DIRECT EXPOSURE TO BEAM (e)

VARO : Avattaessa ja suojalukitus ohitettaessa olet alttiina näkymättömälle lasersäteilylle.Älä katso säteeseen. (d)

VARNING : Osynlig laserstrålning är denna del är öppnad och spårren är urkopplad. Betrakta ej strålen. (s)

ADVARSEL :Usynlig laserstråling ved åbning , når sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling. (f)

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UX-T550

Preventing static electricity

Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.

1.1. Grounding to prevent damage by static electricity

Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players. Be careful to use proper grounding in the area where repairs are being performed.

1.1.1. Ground the workbench

1. Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the traverse unit (optical pickup) on it.

1.1.2. Ground yourself

1. Use an anti-static wrist strap to release any static electricity built up in your body.

(caption) Anti-static wrist strap

Conductive material (conductive sheet) or iron plate

1.1.3. Handling the optical pickup

1. In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.)

2. Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power source can easily destroy the laser diode.

1.2. Handling the traverse unit (optical pickup)

1. Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.

2. Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a time when attaching it to the connector.

3. Handle the flexible cable carefully as it may break when subjected to strong force.

4. It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it

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Disassembly method

Removing the rear panel

(See Fig. 1 and 2)

1.

From behind the body, remove the seven screws A retaining the rear panel.

2.

After turning the body upside down, remove the two screws B retaining the rear panel.

3.

Take out the rear panel from behind the body.

Removing the side panel (L) and (R)

(See Fig. 2 to 5)

Rear panel

Front panel assembly

C

A

Fig. 1

Rear panel

B

1.

After turning the body upside down, remove the two screws C retaining the front cabinet assembly.

2.

After turning the body back to initial position, open the CD door while pressing the upper OPEN button.

3.

While moving the side panel (L) in the arrow direction, remove the panel from the left side of the body.

4.

While moving the side panel (R) in the arrow direction, remove the panel from the right side of the body.

Front panel assembly

Fig. 2

Fig. 3

B

CD door

OPEN button

Front panel assembly

1-6

Side panel (R)

Side panel (L)

Fig. 4Fig. 5

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Removing the CD player unit

(See Fig. 6 to 8)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

From the two connector CN603 and CN604 on the CD servo control board, disconnect the card wires outgoing from the connector CN304 on the power amplifier board and the connector CN766 on the LCD system CPU board.

4.

Disengage the left and right engagements a and b fixing the CD player unit by using a minus screw driver, etc.

CD player unit

CD servo

control board

CN604

a

Front panel assembly

CD player unit

CD servo control board

CN603

Fig. 6

Fig. 8

Power amplifier board

CD player unit

b

Front panel assembly

Fig. 7

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UX-T550

Removing the power amplifier board and heat sink (See Fig. 9 to 11)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

Remove the five screws D and E retaining the heat sink.

5.

From the connector CN303 on the power amplifier board, disconnect the card wire outgoing from the connector CN34 on the head amplifier and mechanism control board.

6.

From the connector CN901 on the power supply board, disconnect the connector wire outgoing from the connector W306 on the power amplifier board.

7.

Remove the one screw F retaining the power amplifier board.

8.

Remove the power amplifier board from the two connectors CN711 and CN712 on the LCD system CPU board.

Heat sink

CN303

D

E

Fig. 9

Power amplifier board

CN711

CN712

9.

After removing the power amplifier board from the key way c on the bottom chassis, take this board out while raising it in the arrow direction.

LCD system CPU board

Power supply board

Power amplifier board

CN901

Heat sink

Fig. 10

Front panel assembly

1-8

Bttom chassis

c

F

Fig. 11

c

UX-T550

Removing the tuner board

(See Fig. 12 and 13)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

From the right side of the body, remove the one screw G retaining the tuner board.

4.

From the connector CN1 on the tuner board, disconnect the card wire outgoing from the connector CN701 on the LCD system CPU board.

5.

Remove each tuner board backward while releasing the joint d.

Removing the front panel assembly

(See Fig. 12 and 14)

1.

Remove the rear panel.

LCD system CPU board

CN701

Joint d

CN1

G

Fig. 12

Tuner board

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

Remove the power amplifier board and heat sink.

5.

From the connector CN701 on the LCD system CPU board, disconnect the card wire outgoing from the connector CN1 on the tuner board.

6.

From the bottom of the body, disengage the engagement e fixing the front panel assembly in Fig. 14 while pressing in with a minus screw driver, eta.

Joint d

Front panel assembly

Fig. 13

e

Fig. 14

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Removing the power transformer and power supply board (See Fig. 15 and 16)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

Remove the power amplifier board and heat sink.

5.

Remove the four screws H retaining the power transformer and power supply board and the one screw I retaining the jack holder.

Power supply board

Power transformer

HH

Fig. 15

Jack holder

Removing the cassette mechanism unit

(See Fig. 17)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

Remove the power amplifier board.

5.

Remove the front panel assembly.

6.

From inside the front panel assembly, remove the four screws J and K retaining the cassette mechanism unit.

7.

From the connector CN33 on the head amplifier and mechanism control board, disconnect the card wire outgoing from the connector CN731 on the LCD system CPU board.

Power supply board

LCD system CPU board

CN731

J

I

Fig. 16

Head amplifier & mechanism

control board

CN33

K

1-10

Cassette mechanism unit

Fig. 17

UX-T550

Removing the function switch board and LCD system CPU board

(See Fig. 18 and 19)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

Remove the front panel assembly.

5.

Remove the cassette mechanism unit.

6.

From inside the front panel assembly remove the two screws L retaining the function switch board.

7.

From the connector CN782 on the LCD system CPU board, disconnect the connector wire outgoing from the connector CN802 on the operation switch board.

8.

While sliding the two engagements f fixing the LCD system CPU board, pull out this board.

Operating switch board

LCD system

CPU board

CN782

f

Function switch board

CN802

L

Fig. 18

Function switch board

L

f

9.

After disconnect the connector CN801 on the function switch board from the connector CN781 on the LCD system CPU board, remove the respective boards while pulling them upward.

LCD system CPU board

Fig. 19

CN801

CN781

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UX-T550

Removing the operating switch board

(See Fig. 20 to 22)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

Remove the front panel assembly.

5.

Remove the cassette mechanism unit.

6.

Remove the LCD system CPU board.

7.

Remove the two screws M retaining the operating switch board.

8.

Remove the MULTI-JOG button.

9.

Remove the VOLUME and POWER / AUX buttons.

10

.

Take out the standby LED lens.

11

.

After removing four pawls g fixing the operating switch board, remove the switch while pulling it in the arrow direction.

MULTI-JOG button

M

VOLUME button

Fig. 20

Operating switch board

g

POWER / AUX button

g

M

Standby LED lens

12

.

Remove the two screws N retaining the operation switch board.

13

.

Remove the six pawls h fixing the operating switch board.

h

Operating switch board

N

h

Fig. 21

h

N

h

Fig. 22

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UX-T550

Removing the playback / recording & eraser head (See Fig. 1 to 3)

1.

While shifting the trigger arms seen on the right side of the head mount in the arrow direction, turn the flywheel R in counterclockwise direction until the head mount has gone out with a click (See Fig. 1).

2.

When the flywheel R is rotated in counterclockwise direction, the playback / recording & eraser head will be turned in counterclockwise direction from the position in Fig. 2 to that in Fig. 3.

3.

At this position, disconnect the flexible P.C. board (outgoing from the playback / recording & eraser head) from the connector CN31 on the head amplifier & mechanism control P.C. board.

4.

Remove the flexible P.C. board from the chassis base.

5.

Remove the spring 1 from behind the playback / recording & eraser head.

Flexible board

Cassette mechanism

Trigger armHead mount

Fig. 1

Playback / Recording & eraser head

Flywheel R

Spring 1

Trigger arm

6.

Loosen the reversing azimuth screw retaining the playback / recording & eraser head.

7.

Take out the playback / recording & eraser head from the front of the head mount.

8.

The playback / recoring & eraser head should also be removed similarly according to steps 1 to 7 above.

Reassembling the playback / recording & eraser head (See Fig.3)

1.

Reassemble the playback head from the front of the head mount to the position as shown in Fig. 3.

2.

Fix the reversing azimuth screw.

3.

Set the spring 1 from behind the playback / recording & eraser head.

4.

Attach the flexible P.C. board to the chassis base, as shown in Fig. 3.

5.

The playback / recording & eraser head should also be reassembled similarly to step 1 to 4 above.

CN31

Head amplifier & mechanism control P.C. board

Fig. 2

Playback / Recording & eraser head

Spring 1

Fig. 3

Flywheel R

Reversing azimuth screw

Head mount

Flexible board

Head amplifier & mechanism control P.C. board

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Removing the head amplifier & mechanism control board (See Fig. 4)

1.

Remove the cassette mechanism assembly.

2.

After turning over th cassette mechanism assembly, remove the three screws A retaining the head amplifier & mechanism control board.

A

CN32

A

Belt

Main motor assembly

3.

Disconnect the connector CN32 on the board including the connector CN 1 on the reel pulse P.C. board.

4.

When necessary, remove the 4 pin parallel wire soldered to the main motor.

Removing the main motor assembly

1.

Remove the two screws B retaining the main motor assembly (See Fig. 4 and 4a).

2.

While raising the main motor, remove the capstan belt from the motor pulley (See Fig. 4a).

CAUTION:

Be sure to handle the capstan belt so carefully that this belt will not be stained by grease and other foreign matter. Moreover, this belt should be hanged while referring to the capstan belt hanging method in Fig. 5 and 6.

Head amplifier & mechanism control board

Flexible board

Capstan belt

CN31

A

Fig. 4

Main motor assembly

B

4pin parallel wire

Main motor assembly

Motor pulley

1-14

Capstan belt

Fig. 5

Fig. 4a

Mechanism motor assembly

Main motor assembly

Flywheel

Motor pulley

Motor pulleyCapstan belt

Fig. 6

Removing the flywheel (See Fig. 7 and 8)

1.

Remove the head amplifier & mechanism control P.C. board.

2.

Remove the main motor assembly.

3.

After turning over the cassette mechanism, remove the two slit washers 1 and fixing the capstan shafts R and L, and pull out the flywheel R and L respectively from behind the cassette mechanism.

UX-T550

Flywheel R Flywheel L

Capstan shaft R Capstan shaft L

Flywheel R Flywheel L

Fig. 8

Removing the reel pulse P.C. board and solenoid (See Fig. 9)

1.

Remove the five pawls a to e reattaining the reel pulse board.

2.

From the surface of the reel pulse board parts, remove the two pawls f and g retaining the solenoid.

a b c d e

g

f

Solenoid

Slit washer 1

Fig. 7

Reel pulse board

Fig. 9

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UX-T550

Removing the CD mechanism and CD servo control P.C. board (See Fig. 1 and 2)

1.

Remove the rear panel.

2.

Remove the left and right side panels.

3.

Remove the CD player unit.

4.

After turning back the CD player unit, remove the four screws A retaining the CD servo control board and shield.

5.

From the connector CN601 on the CD servo control board, disconnect the card wire outgoing from the CD mechanism.

6.

From the connector P011 on the CD mechanism P.C. board, disconnect the connector wire outgoing from the connector CN602 on the CD servo control board.

7.

Remove the four screws B retaining the CD mechanism.

A

P011

Shield

CN601

CN602

CD mechanism board

Fig. 1

A

CD servo control board

A

8.

While sliding the CD mechanism in the arrow direction, take turn table out so carefully that it does not come into contact with the chassis.

B

BB

CD mechanism

B

Fig. 2

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Adjustment method

Measurement instruments required for

adjustment

1. Low frequency oscillator This oscillator should have a capacity to output 0dBs to 600 at an oscillation frequency of 50Hz-20kHz.

2. Attenuator impedance : 600

3. Electronic voltmeter

4. Distortion meter

5. Frequency counter

6. Wow & flutter meter

7. Test tape VT712 : Tape speed and running unevenness (3kHz) VT724 : Reference level (1kHz) TMT7036 : Head angle (10kHz), playback frequency characteristics (1kHz) and dubbing frequency characteristics (63, 1 and 10kHz) Because of frequency -mixed tape with 63, 1, 10 and 14kHz (250nWb/m - 24dB), use this tape together with a filter.

8. Blank tape TYPE : AC-225 TYPE : AC-514

9. Torque gauge : For play and back tension FWD(TW2111A), REV(TW2121a) and FF/REW(TW2231A)

Measurement conditions

Power supply voltage Reference output

Headphone : 0.245V/32 Reference frequency and input level Input for confirming recording and playback characteristics Measurement output terminal Load resistance

AC230V (50Hz)

Speaker : 0.775V/4

1kHz, AUX : -8dBs

AUX : -28dBs

Speaker J3002

Tuner section

Voltage applied to tuner +B : DC5.7V VT : DC 12V Reference measurement 26.1mV(0.28V)/4 output Input positions AM : Standard loop antenna FM : TP1 (hot) and TP2 (GND)

Standard measurement position of volume

Bass Off Active hoper bass pro Off Up and down adjustment of volume VOL : 23

Precautions for measurement

1. Apply 30pF and 33k to the IF sweeper output side and 0.082 F and 100k in series to the sweeper input side.

2. The IF sweeper output level should be made as low as possible within the adjustable range.

3. Since the IF sweeper is a fixed device, there is no need to adjust this sweeper.

4. Since a ceramic oscillator is used, there is no need to perform any MIX adjustment.

5. Since a fixed coil is used, there is no need to adjust the FM tracking.

6. The input and output earth systems are separated. In case of simultaneously measuring the voltage in both of the input and output systems with an electronic voltmeter for two channels, therefore, the earth should be connected particularly carefully.

7. In the case of BTL connection amp., the minus terminal of speaker is not for earthing. Therefore, be sure not to connect any other earth terminal to this terminal. This system is of an BTL system.

8. For connecting a dummy resistor when measuring the output, use the wire with a greater code size.

9. Whenever any mixed tape is used, use the band pass filter (DV-12).

4

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Radio Input signal

AM frequency 400Hz AM modulation 30% FM frequency 400Hz FM frequency deviation 22.5kHz

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<<Arrangement of adjusting positions>>

Cassette mechanism section

Head azimuth adjusting screw (Forward side)

Head azimuth adjusting screw (Reverse side)

Cassette mechanism section (Bottom side)

Head azimuth adjusting screw (Forward side)

Playback/Recording & eraser head

Head azimuth adjusting screw (Reverse side)

Playback/Recording & eraser head

Front panel assembly section

VR37

L031

Bias TP

VR31

1-18

VR32

Tape Recorder Section

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Items

Confirmation of head angle

Confirmation of tape speed

Measurement conditions

Test tape : TMT7036 (10kHz) Measurement output terminal : Speaker terminal Speaker R (Load resistance: 4 ) : Headphone terminal

Test tape : VT712 (3kHz) or TMT7036 (3kHz) Measurement output terminal : Headphone terminal

Measurement method

1 Playback the test tape TMT7036 (10kHz) 2 With the recording & playback mechanism, adjust the head azimuth screw so that the forward and reverse output levels become maximum. After adjustment, lock the head azimuth at least by half turn. 3 In either case, this adjustment should be performed in both the forward and reverse directions with the head azimuth screw.

Adjust VR37 so that the frequency counter reading becomes 3,010Hz 15Hz when playing back the test tape VT712 (3kHz) with playback and recording mechanism after ending forward winding of the tape.

Reference Values for Confirmation Items

Standard Values

Maximum output

Tape speed of deck : 3,010Hz 15Hz

Adjusting positions

Adjust the head azimuth screw only when the head has been changed.

VR37

Items

Difference between the forward and reverse speed

Wow & flutter Test tape

Measurement conditions

Test tape : VT712 (3kHz) or TMT7036 (3kHz) Measurement output terminal : Speaker terminal Speaker R (Load resistance: 4 ) Measurement output terminal : Headphone

: VT712 (3kHz) or TMT7036 (3kHz) Measurement output terminal : Headphone terminal

Measurement method

When the test tape VT712 (3kHz) has been played back with the recording and playback mechanism at the beginning of forward winding, the frequency counter reading of the difference between both of the mechanism should be 6.0Hz or less.

When the test tape VT712 (3kHz) has been played back with the recording and playback mechanism at the beginning of forward winding, the frequency counter reading of wow & flutter should be 0.25% or less (WRMS).

Standard Values

6.0Hz or less

0.25% or less (WRMS)

Adjusting positions

Head azimuth screw (See Fig. 34)

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Electrical Performance

Items

Adjustment of recording bias current (Reference Value)

Adjustment of recording and playback frequency characteristics

Measurement conditions

Mode: Forward or reverse mode Recording mode Test tape : AC-514 to TYPE and AC-225 to TYPE Measurement output terminal : Both recording and headphone terminals

Reference frequency : 1kHz and 10kHz (REF.: -20dB) Test tape : AC-514 to TYPE Measurement input terminal : OSC IN

Measurement method

1 With the recording and playback mechanism, load the test tapes (AC-514 to TYPE and AC-225 to TYPE ), and set the mechanism to the recording and pausing condition in advance. 2 After connecting 100 in series to the recorder head, measure the bias current with a valve voltmeter at both of the terminals. 3 After resetting the [PAUSE] mode, start recording. At this time, adjust VR31 for Lch and VR32 for Rch so that the recording bias current values become 4.0 A (TYPE ) and 4.20 A (TYPE ).

1 With the recording and playback mechanism, load the test tapes (AC-514 to TYPE ), and set the mechanism to the recording and pausing condition in advance. 2 While repetitively inputting the reference frequency signal of 1kHz and 10kHz from OSC IN, record and playback the rape. 3 While recording and playback the test tape in TYPE , adjust VR31 for Lch and VR32 for Rch so that the output deviation between 1kHz and 10kHz becomes

-1dB 2dB.

Standard Values

AC-225 : 4.20 A AC-514 : 4.0 A

Output deviation between 1kHz and 10kHz : -1dB 2dB

Adjusting positions

L ch : VR31 R ch : VR32

Reference Values for Electrical Function Confirmation Items

Items

Recording bias frequency

Eraser current (Reference value)

Measurement conditions

Forward or reverse Test tape : TYPE (AC-514) Measurement terminal : BIAS TP on P.C. board

Forward or reverse Recording mode Test tape : AC-514 to TYPE and AC-225 to TYPE Measurement terminal : Both of the eraser head terminals

Measurement method

1 While changing over to and from BIAS 1 and 2, confirm that the frequency is changed. 2 With the recording and playback mechanism, load the test tape. (AC-514 to TYPE ), and set the mechanism to the recording and pausing condition in advance. 3 Confirm that the BIAS TP frequency on the P.C. board is 100kHz 6kHz.

1 While recording and playback mechanism, load the test tapes (AC-514 to TYPE and AC-225 to TYPE ), and set the mechanism to the recording and pausing conditions in advance. 2 After setting to the recording conditions, connect 1W in series to the eraser head on the recording and playback mechanism side, and measure the eraser current from both of the eraser terminals.

Standard Values

100 kHz 6 kHz

TYPE : 120 mA TYPE : 75 mA

Adjusting positions

1-20

Flow of Functional Operation Until TOC Read

Power ON

Power Key

Slider turns REST SW ON.

Automatic tuning of TE offset

Check that the voltage at the pin17 of CN604 is 0V (a moment)?

UX-T550

Check Point

Tracking error waveform at TOC reading

pin 25 of IC601(TE)

Approx

1.8V

VREF

Disc status to rotate

Approx.3sec

Tracking servo off status

Automatic measurement of TE amplitude and automatic tuning of TE balance

Tracking servo on status

Disc to be braked to stop

TOC reading finishes

500mv/div 2ms/div

Fig.1

Laser ON

Detection of disc

Automatic tuning of Focus offset

Automatic measurement of Focus A-curve amplitude

Disc is rotated

Focus servo ON (Tracking servo ON)

Automatic measurement of Tracking error amplitude

Automatic tuning of Tracking error balance

Check that the voltage at the pin3 of IC601 + side is + 5V?

Confirm that the Focus error S-cuve signal at the pin27 of IC601 is approx.2Vp-p

Confirm that the signal from pin24 IC603 is 0V as a accelerated pulse during approx.400ms.

Confirm the waveform of the Tracking error signal at the pin25 of IC601 (R612) (See fig-1)

Automatic tuning of Focus error balance

Automatic tuning of Focus error gain

Automatic tuning of Tracking error gain

TOC reading

Play a disc

Confirm the eys-pattern at the lead of TP1

1-21

UX-T550

Maintenance of Laser Pickup

(1) Cleaning the pick up lens Befor you replace the pick up, please try to clean the lens with a alcohol soaked cotton swab.

(2) Life of the laser diode (Fig.1) When the life of the laser diode has expired, the following symptoms wil appear. (1) The level of RF output (EFM output:ampli tude of eye pattern) will below.

Is RF output

1.1 0.15Vp-p?

YES

O.K

NO

Replace it.

Replacement of Laser Pickup

Turn off the power switch and,disconnect the power cord from the ac outlet.

Replace the pickup with a normal one.(Refer to " Pickup Removal " on the previous page)

Plug the power cord in,and turn the power on. At this time,check that the laser emits for about 3seconds and the objective lens moves up and down. Note: Do not observe the laser beam directly.

Play a disc.

(Fig.1)

(3) Semi-fixed resistor on the APC PC board The semi-fixed resistor on the APC printed circuit board which is attached to the pickup is used to adjust the laser power.Since this adjustment should be performed to match the characteristics of the whole optical block, do not touch the semi-fixed resistor. If the laser power is lower than the specified value,the laser diode is almost worn out, and the laser pickup should be replaced. If the semi-fixed resistor is adjusted while the pickup is functioning normally,the laser pickup may be damaged due to excessive current.

Check the eye-pattern at TP1.

Finish.

1-22

Description of major ICs

AN8806SB (IC601) : RF&Servo AMP

1.Pin layout

PD LD LDON LDP VCC RF- RF OUT RF IN

C.AGC ARF C.ENV

C.EA

CS BDO BDO

CS BRT OFTR /NRFDET

GND

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16 17 18

36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19

UX-T550

PDAC PDBD PDF PDE PDER PDFR TBAL FBAL EF EF OUT TE TE OUT CROSS TE BPF VDET LD OFF VREF ENV

2.Block diagram

36

-+

35

--

+

31

34

-+

32

33

-+

6

--

VCBA

+

29

728

-+

--

+

VCBA

--

+

VCBA

--

VCBA

+

--

-+

+

--

27

-+

--

EQ

+

--

+

--

910 17

8

AGC

OFTR

BDO

RF DET

11

12 19

ENV CURCUIT

13

14

15

16

-+

20

21

2

24 25

30

14

23

26

22

3

1-23

UX-T550

3. Pin function

AN8806SB

Pin No.

1

2

3 4 5

6

7 8

9 10 11 12 13 14 15 16 17 18

19

20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

Symbol

PD

LD

LD ON

LDP

VCC

RF-

RF OUT

RF IN

C.AGC

ARF

C.ENV

C.EA

CS BDO

BDO

CS BRT

OFTR

/NRFDET

GND

ENV

VREF

LD OFF

VDET

TE BPF

CROSS

TE OUT

TE-

FE OUT

FE-

FBAL

TBAL

PDFR

PDER

PDF

PDE

PD BD

PD AC

I/O

I

APC amp input terminal

APC amp output terminal

O

APC ON/OFF control terminal

I

--

Connect to ground

Power supply

--

Inverse input pin for RF amp

I

RFamp output

O

RF input

I

Connecting pin of AGC loop filter

I/O

RF output

O

I/O

A capacitor is connected to this terminal to detect the envelope of RF signal

I/O

A capacitor is connected to this terminal to detect the envelope of RF signal

A capacitor is connected to detect the lower envelope of RF signal

I/O

BDO output pin

O

A capacitor is connected to detect the lower envelope of RF signal

I/O

O

Of-track status signal output

RF detection signal output

O

--

Ground

O

Envelope output Reference voltage output

O

--

Connect to ground

O

Vibration detection signal output

I

Input pin of tracking error through BPF

O

Tracking error cross output

O

Tracking error signal output Inverse input pin for tracking error amp

I

O

Output pin of focus error Inverse input pin for focus error amp

I I

Focus balance control

I

Tracking balance control F I-V amp gain control

I/O

E I-V amp gain control

I/O

I

I-V amp input I-V amp input

I I

I-V amp input

Function

I I-V amp input

1-24

MN35510 (IC603) : Digital servo & digital signal processor

UX-T550

1. Pin layout

2.Block diagram

LRCKIN(MSEL) BCLK(SSEL) SRDATAIN (PSEL)

IOSEL

CLVS CRC BLKCK CLDCK SBCK SUBC DEMPH RESY FLAG6(RESY)

SSEL SQCK SUBQ AVDD2

AVDD2

PCK EFM PLLF DSLF IREF DRF ARF RSEL PSEL

MLD MCLK MDATA

CK384(EFM) VCOF BYTCK SMCK FCLK CSEL MSEL X2 X1

ÊSTAT

DIGITAL DEEMPHSIS

SUB CODE BUFFER

DSL. PLL VCO

VCO

ITUNING GENERATION PITCH CONTROL

20 ~ 1

21

~

40

41 ~ 60

8TIMES OVER SAMPUNC DIGITAL FILTER

EFM DEMODULATION

SYNC INTERPOLATION

SUBCODE DEMODULATION

MICRO COMPUTER INTERFACE

A/D

COVERTER

80

~

61

1BIT DAC LOGIC S

16k SRAM

CIRC ERROR CORRECTION DEINTERLEVE

CLV SERVO

INPUT

PEM (R)

PEM (L)

D/A CONVERTER

OUTPUT

DIGITAL AUDIO INTERFASE

INTER POLATION SOFT MUTING DIGITAL ATTENUATION PEAK DETECTIVE AUTO CUE

PORT

SERVO TIMING GENERATOR

AVSS1 AVDD1 OUTR

OUTL

FLAG IPFLAG

TX

ECM

PC

LRCK SRDATA BCLK DMUTE

TRKV KICK VREF TRVSTR ECS TVD TRD FOD TBAL FBAL TOFS TES /TLOCK /FLOCK PLAY LDON WVEL SENSE

D

/

D

V

S

D

S

D

D 1

/

R

V

T

S

E

T

S

1

T

F E

R

T

F

E

E N V

T R C R S

B

V

D

O

E T

/ R F D E

O F T

1-25

UX-T550

3. Pin function

Pin No.

1

2 3 4 5 6

7

8

9 10 11

12 13 14 15 16

17

18 19 20

21 22 23

24

25

26 27 28

29

30 31 32 33 34 35 36 37 38

39 40

symbol

BCLK LRCK SRDATA DVDD1 DVSS1 TX

MCLK

MDATA MLD SENSE FLOCK TLOCK

BLKCK SQCK SUBQ DMUTE

STATUS

RST

SMCK

PMCK

TRV

TVD

PC

ECM

ECS

KICK TRD FOD

VREF

FBAL TBAL FE TE RF ENV VDET OFT TRCRS

RFDET BDO LDON

I/O

O O O

I I

O

I

I I

O O

I

O

I

O O

O

O O O

I

O O

I I I I I I I I

O

Function

Not used Not used Not used Power supply (Digital) Connected to GND Digital audio interface output

com command clock signal input

(Data is latched at signal's rising point)

com command data input

com command load signal input Not used Not used

Not used sub-code block clock signal output Outside clock for sub-code Q resister input Sub-code Q -code output

I

Connected to GND Status signal

(CRC,CUE,CLVS,TTSTOP,ECLV,SQOK) Reset signal input (L:Reset)

Not used

I

Not used

Traverse enforced output

Traverse drive output

I

Not used

Spindle motor drive signal (Enforced mode output) 3-State Spindle motor drive signal (Servo error

signal output)

Kick pulse output

Tracking drive output

Focus drive output Reference voltage input pin for D/A

output block (TVD,FOD,FBA,TBAL) Focus Balance adjust signal output Tracking Balance adjust signal output Focus error signal input(Analog input) Tracking error signal input(Analog input)

RF envelope signal input(Analog input) Vibration detect signal input(H:detect) Off track signal input(H:off track)

Track cross signal input RF detect signal input(L:detect)

BDO input pin(L:detect)

Laser ON signal output(H:on)

Pin No.

41 42 43 44 45 46

47

48 49 50 51

52 53 54 55 56

57

58 59 60 61 62

63

64

65

66

67

68

69

70 71 72

73

74

75 76

77

78

79

80

symbol

TES

PLAY

WVEL ARF

IREF

DRF

DSLF

PLLF

VCOF AVDD2

AVSS2

EFM PCK PDO SUBC SBCK

VSS

XI

X2

VDD BYTCK

CLDCK

FCLK

IPPLAG

FLAG

CLVS CRC

DEMPH

RESY

IOSEL TEST

AVDD1

OUT L AVSS1

OUT R

RSEL

CSEL

PSEL

MSEL

SSEL

I/O

Tracking error shunt signal output(H:shunt)

O

I

Not used

I

Not used

I

RF signal input

Reference current input pin

I

Bias pin for DSL

I

I/O

Loop filter pin for DSL

Loop filter pin for PLL

I/O

I

Not used

I

Power supply(Analog) Connected to GND(Analog)

Not used

II I

Not used

I

Not used

I

Not used

I

Not used

Connected to GND(for X'tal oscillation

I

circuit)

Input of 16.9344MHz X'tal oscillation circuit

I

Output of X'tal oscillation circuit

O

I

Power supply(for X'tal oscillation circuit)

I

Not used

I

Not used

I

Not used

I

Not used

I

Not used

I

Not used

I

Not used Not used

I

Not used

III

pull up pull up

Power supply(Digital)

Lch audio output

O

I

Connected to GND Rch audio output

O

II

pull up

Connected to GND

I

Connected to GND

I

Connected to GND

I

Pull up

Function

MN35510

1-26

BH3852S (IC38) : E.Volume

1. Block diagrams

FILTER

IN2

NF2

BVN2

24 23 22 21 20 19 18 17 16 15 14 13

BIN2

BVO2

TIN2

2K

(BASS) (TREBLE) TONE CONTROL

20K

TVO2

OOUT2VCTC

10M 10M 10M

UX-T550

BC

- +

Vcc

20K

+

20K

1 2 3 4 5 6 7 8 9 10 11 12

IN1

GND

+

47K

+

-

20K

TONE CONTROL (BASS) (TREBLE)

NF1

BVN1

MATRIX SURROUND SOUND

VOLUME VOLUME

2K

BVO1

TIN1

BIN1

TVO1

CONTROL

- +

Vcc

OUT1

2. Pin function

Function

13 14 15 16

17.18

1 2 3

Symbol

GND

IN1

NF1

I/O

Connect to GND.

Terminal for 1ch volume input.

I

Terminal for gain adjustment of

I

Pin No. Pin No.

input step AMP.

4~6

BASS1

Terminal for connection of 1ch

low-frequency filter.

7.8

TRE1

Terminal for connection of 1ch

-

19~21

high-frequency filter.

9 10 11 12

OUT1

VCC LIVE

VREF

Terminal for 1ch volume output.

O

Terminal for power supply.

Terminal for surround control.

Terminal for reference voltage

O

22

23 24

output.

VOLUMEVOLUME

10M

SC

Symbol

BASS

TRE

VOL OUT2 TRE2

BASS2

NF2

IN2

VSET

Ref. Voltage

VREF

I/O

I I I

O

-

I

-

Function

Terminal for bass control. Terminal for treble control. Terminal for volume control. Terminal for 2ch volume output. Terminal for connection of 2ch high-frequency filter. Terminal for connection of 2ch low-frequency filter. Terminal for gain adjustment of input step AMP. Terminal for 2ch volume input. Terminal for filter.

1-27

UX-T550

BU4094BCF-X (IC33) : SHIFT / STORE register

1. Pin layout

16 15 14 13 12 11 10 9

VDD Q5 Q6 Q7 Q8 Q'S QS

STROBE DATA CLOCK Q1 Q2 Q3 Q4 Vss

OUTPUT ENABLE

1 2 3 4 5 6 7 8

2. Block diagram

DATA

CLOCK

STROBE

OUTPUT

ENABLE

2

8-STAGE

3

1

SHIFT REGISTER

8-BIT

LATCHES

15

3-STATE

OUTPUTS

Q1 Q8

10

9

Q'S

QS

SERIAL OUTPUT

1-28

PARALLEL OUTPUT

KIA78S06P (IC703) : Regulator

UX-T550

1.Pin layout

123

3.Block diagram

Q14

Z1

R9

Q16

R10

Q1

Q2

Q7

Q4

R1

2. Pin function

Q3

Q6

R2

Q8

Pin No.

C1

1 2 3

Q5

R4

Q9

Function

Output

Common

Input

Q11

Q10

Q12

R8

Q13

R7

R5

3

INPUT

2

OUTPUT

R11

R3

R6

1

COMMON

1-29

UX-T550

LA4705NA (IC31) : 2ch BTL power IC

1. Pin layout

2. Block diagram

LA4705N

123456789101112131415161718

GND

2

4

5

7

RIPPLE

FILTER

IN

BIAS

CIRCUIT

STANDBY

SW

IN

PREDRIVER

NC Vcc1

OUTPUT PIN TO Vcc

POWER

LOAD SHORT PROTECTOR

POWER

OVER VOLTAGE/ SURGE PROTECTOR

THERMEL SHUTDOWN

POWER

LOAD SHORT PROTECTOR

SHORT PROTECTOR

OUTPUT PIN TO GND

Vcc

SHORT PROTECTOR

OUTPUT PIN TO GND SHORT PROTECTOR

1813

17

POWER

16

GND1

15

14

POWER

13

GND2

1-30

POP NOISE

PREVENTION

CIRCUIT

PREDRIVER

POWER

OUTPUT PIN TO Vcc SHORT PROTECTOR

68910 11

Vcc2NCNC

12

LC72136N (IC2) : PLL frequency synthesizer

1. Pin layout

FM/AM

CLOCK

FM/ST/VCO

AM/FM

2. Block diagram

XT

CE

DI

DO

SDIN

1 2 3 4 5 6 7 8 9 10 11

22 21 20 19 18 17 16 15 14 13 12

XT GND LPFOUT LPFIN PD VCC FMIN AMIN

IFCONT IFIN

UX-T550

1

22

16

15

3

4

5

6

17

21

3. Pin function

Symbol

No.

1

2

3

4

5

6

7

8

9

10

11

XT

FM/AM

CE

DI

CLOCK

DO

FM/ST/VCO

AM/FM

LW

MW

SDIN

Reference

Driver

Swallow Counter

1/2

C

2

B

I/F

Powe r

on

Reset

Function

I/O

X'tal oscillator connect (75kHz)

I

LOW:FM mode

O

When data output/input for 4pin(input) and

I

Swallow Counter

1/16,1/17 4bit

12bit

Programmable

DriverS

Data Shift Register & Latch

7821113

6pin(output): H

Input for receive the serial data from

I

controller

Sync signal input use

I

Data output for Controller

O

Output port

"Low": MW mode

O

Open state after the power on reset

O

Input/output port

I/O

Input/output port

I/O

Data input/output

I/O

Phase

Detector

Charge Pump

Unlock

Detector

Universal

Counter

Symbol

No.

12

IFCONT

13

14

15

16

17

18

19

LPFOUT

20

21

22

IFIN

AMIN

FMIN

VCC

PD

LPFIN

GND

XT

18

19

20

12

I/O

Function IF counter signal input

I

IF signal output

O

Not use

-

AM Local OSC signal output

I

FM Local OSC signal input

I

Power suplly(VDD=4.5-5.5V)

When power ON:Reset circuit move

PLL charge pump output(H: Local OSC

O

frequency Height than Reference frequency.

L: Low Agreement: Height impedance)

Input for active lowpassfilter of PLL

I

Output for active lowpassfilter of PLL

O

Connected to GND

X'tal oscillator(75KHz)

I

1-31

UX-T550

TA2057N (IC1) : FM / AM IF AMP & Detector

1.Block d iagrams

FM IF IN

24 23 22 21 20 19 18 17 16 15 14 13

AM MIX OUT Vstb QUAD FM OUT AM OUT MPX IN LPF 1 LPF 2 VCO L OUT

AM IF IN

AM MIX

123456789 1110 12

AM RF IN

2.Pin function

No.

I/O

1

I

2

3

4

-

5

6

7

8

9

10

11

12

AM OSC OUT

O

-

I

-

O

REG

FM IF

S.SENSFMS.SENS

Symbol

AM RF

AM S.SENS

FM S.SENS

AM OSC

VCC

AGC

GND

IF OUT

TU IND

ST IND

Rch OUT

FM DET

AM IF

AM OSC

AM OSCAMOSC

AMRF signal input

AM local oscillation circuit

AM local oscillation signal output

Power supply

AGC voltage input terminal

Connect to GND

IF REQ signal output to IC2

Indicator drive output when tuning

Stereo indicator output

"H"mono . "L"stereo

Output Rch

BUFF

Vcc AGC GND IF OUT

OUT

Function Function

AM DET

Pin No.

13

14

15

16

17

18

19

20

21

22

23

24

AGC

I/O

O

I

O

I

-

O

I

AM

LEVEL SW

IF BUFF

IF REQ SW

Symbol

Lch OUT

VCO

LPF2

LPF1

MPX IN

AM OUT

FM OUT

FM QUAD

AM IF IN

Vst

AM MIX OUT

FM IF IN

VCO

DIVIDE

DECODE

AM/FM MONO SW

TUN LED

/REQ

TUN LED

Output Lch

Voltage controlled terminal

When voltage of terminal is MONO

at "H" and ST at "L"

When voltage of terminal is AM at

"H" and FM at "L"

Multi plex signal input

AM detection signal output

FM detection signal output

Bypass to FMIF

Input of AMIF signal

Fixed voltage output terminal

Output terminal for AM mixer

Input of FMIF signal

ST LED

MUTE

R OUTAM

1-32

UPD78064GF-149 (IC701) : System CPU

1.Pin layout

100 ~ 81

1

80

UX-T550

~

30

31 ~ 50

2.Pin function

Symbol

No.

USDATA

1

USCK

2

UQRIN

3

UNC

4

USQCK

5

ICVSS

6

UX2

7

UX1

8

VDD

9

UXT1

10

UXT2

11

URESET

12

UREM

13

URDSCK

14

UJOG1

15

UBEAT2

16

UBEAT1

17

U+BCTL

18

UXRESET

19

UMCLK

20

UMDATA

21

UMLD

22

UPBMUTE

23

ULATCH

24

UREEL

25

UFAUX

26

UAVSS

27

USAFEYCD

28

~

51

I/O I/O

Serial data Serial clock

O

CD Q code data

I

Non connect

-

CD Q code data synchronizing clock

O

Connected to VSS

-

Main system clock

-

Main system clock

I

Power supply

-

Sub system clock

I

Sub system clock

-

Reset

I

Remote control

I

Non connect

-

Jog encoder 1

I

Main clock selection 2

O

Main clock selection 1

O

Switched 5V control

O

CD LSI reset

O

CD LSI command clock

O

CD LSI command data

O

CD LSI command load

O

Tape playback mute

O

Tape IC strobe

O

Tape end detection

I

Function AUX

O

AD converter GND

-

CD abnormal voltage detection

I

Function

Pin No.

29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

51~54

55

56~58

59

60~99

100

Symbol

URESET/CLOSE

USAFETY1 USAFETY0

UKEY1

UKEY0 UTAPE0 UTAPE1

AVDD

UAVREF

UBUP

UFTUNER

VSS

UMPX

UPERIOD

UJOGB UBASS

UTRE UVOL

USBASS

USMUTE

UPOUT

UFCD

COM0~3

BIAS

VLC0~2

VSS

S0~39

USTATUS

I/O

[RESET/CLOSE] switch

I

Abnormal voltage detection 1

I

Abnormal voltage detection 2

I

Body key input 1

I

Body key input 0

I

Tape switch 0

I

Tape switch 1

I

AD converter power supply

-

AD converter reference voltage

-

Backup power supply decision

I

Function tuner

O

GND

-

FM stereo detection

I

Tuner PLL strobe

O

JOG encoder 2

I

BASS control

O

TRE control

O

VOL.control

O

AHB on/off

O

System muting

O

Power ON/OFF

O

Function CD

O

LCD common

O

LCD bias voltage

-

LCD bias voltage

-

GND

-

LCD segment

O

LCD LSI status

I

Function

1-33

UX-T550

AN7317 (IC32) : Pre Amp.

1. Pin layout & Block diagram

16 15 14 13 12 11 10 9

Pre-in Pre-NF Pre-out Rec-in Rec-out Rec-Mute R.R. Vcc

1 2 3 4 5 6 7 8

2. Pin function

Pin No.

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

Pre

Rec

ALC

MUTE R.R.

Pre-in Pre-NF Pre-out Rec-in Rec-out GND

ALC Low-cut

ALC Time

Function Channel 1 playback amplifier input Channel 1 playback amplifier negative feedback Channel 1 playback amplifier output Channel 1 recording amplifier input Channel 1 recording amplifier output ALC low-cut ALC time Ground Vcc Ripple filter Record amplifier mute Channel 2 record amplifier output Channel 2 record amplifier input Channel 2 playback amplifier output Channel 2 playback amplifier negative feedback Channel 2 playback amplifier input

BA3126N (IC31) : Head select switch

1. Pin layout & Block diagram

REC

SW

G

P/B

SW

CONT.

1 2 3 4 5 6 7 8 9

1-34

GND

Vcc

P/B

SW

G

REC

SW

BA6897FP (IC602) : 4channel driver

1.Pin layout

UX-T550

CH1-OUTA

CH1-OUTB

CH1-INA

CH1-INB

TEST1

TEST2

MUTE

CH2-INB

CH2-INA

CH2-OUTB

CH2-OUTA

GND

D.BUF

1

2

D.BUF

3

4

5

6

7

8

9

10

D.BUF

11

12

D.BUF

13

- + Level

shift

-+

+-

Level

shift

- +

T.S.D

DRIVER

MUTE

+ Level

shift

Level

shift

+ -

D.BUF

+-

-+

D.BUF

28

27

26

25

24

23

22

21

20

19

18

CH3-OUTB

17

CH3-OUTA

16

OP IN(+)

GND

CH4-OUTA

CH4-OUTB

CH4-INA

CH4-INB

BIAS IN

Vcc

CH3-INB

CH3-INA

OP-OUT

14

-+

15

OP IN(-)

BA15218N (IC32 / IC35) : Dual Ope. Amp.

+

1

-

1 2 3 4 5 6 7 8

OUT1 +IN1 +IN1

+IN2 -IN2 OUT2

GND

2

-

Vcc

1-35

UX-T550

VICTOR COMPANY OF JAPAN, LIMITED

AUDIO & COMMUNICATION BUSINESS DIVISION PERSONAL & MOBILE NETWORK BUSINESS UNIT. 10-1,1chome,Ohwatari-machi,Maebashi-city,371-8543,Japan

(No.20908)

Printed in Japan 200101(V)

JVC UX-T550 SERVICE MANUAL

Specifications and Main Features

Frequently Asked Questions

User Manual

Important for Laser Products

Preventing static electricity

Disassembly method

Adjustment method

Flow of Functional Operation Until TOC Read

Maintenance of Laser Pickup

Replacement of Laser Pickup

Description of major ICs