JVC UXF-70-MD, UXF-72-MD Service manual

UX-F70MD/UX-F72MD

SERVICE MANUAL

MICRO COMPONENT MD SYSTEM

UX-F70MD UX-F72MD

COLOR

DIMMER

REV.MODE

STANDBY/ON

CLOCK

MD GROUP

SLEEP

FM MODE

/TIMER

MD TITLE

MARK

1 2 3

IMPUT/EDIT

DISPLAY

4 5 6

/CHARA

MD TITLE

7 8 9

SET

CANCEL

ENTER

REPEAT

PLAY MODE

FM/AM

/AUX

BEEP

SOUND

AHB

VOLUME

MODE

PRO

RM-SUXF70MDU

MICRO COMPONENT MD SYSTEM UX-F70MD

PHONES

STANDBY/ON

COMPACT

DIGITAL AUDIO

Contents

Safety precautions Preventing static electricity Important for laser products Disassembly method Adjustment Method 1 (CD/MD section) Adjustment Method 2 (Cassette mechanism section) Flow of functional operation until TOC read (CD)

1-2 1-3 1-5 1-6

1-35

1-38

1-40

COLOR

DIMMER

REV.MODE

STANDBY/ON

CLOCK

FM MODE

MD GROUP

SLEEP

/TIMER

MD TITLE

MARK

1 2 3

IMPUT/EDIT

DISPLAY

4 5 6

/CHARA

MD TITLE

7 8 9

SET

CANCEL

ENTER

REPEAT

PLAY MODE

FM/AM

TAPE

/AUX

BEEP

SOUND

AHB

VOLUME

MODE

PRO

RM-SUXF70MDU

SP-UXF72MD

PHONES

CA-UXF72MDCA-UXF70MDSP-UXF70MD SP-UXF70MD

MICRO COMPONENT MD SYSTEM UX-F72MD

COMPACT

DIGITAL AUDIO

STANDBY/ON

Area Suffix

UB UF

Flow of functional operation until TOC read (MD) Maintenance of laser pickup Replacement of laser pickup Maintenance of MD pickup Procedures of changing the MD pickup Description of major ICs

SP-UXF72MD

Hong Kong

China

1-41 1-42 1-42 1-43

1-43 1-44~71

This service manual is printed on 100% recycled paper.

No.21028

1-1

Sep. 2001

UX-F70MD/UX-F72MD

Safety Precautions

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

0.15 F AC TYPE

1500 10W

Good earth ground

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

Place this probe on each exposed metal part.

CAUTION

1-2

Warning

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.

UX-F70MD/UX-F72MD

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

1-3

UX-F70MD/UX-F72MD

CN451

MAIN board

CN321

CD SERVO board

Pickup

Soldering part b

1.3. Cautions on removing the CD traverse unit

* For removing the CD traverse unit in detail, refer to the "Adjustment Method" section of this manual.

1. Before disconnecting the flexible wire from the connector CN601 on the CD SERVO board, solder the part shown in the figure below. (Note:If the flexible wire is disconnected from the CN601 without presoldering, it may cause breakdown of the CD pickup assembly.)

2. When reassembling the CD traverse unit, be sure to remove the solder from the soldered part after reconnecting the flexible wire to the CN601.

CD SERVO board

CN601

1-4

Soldering part

UX-F70MD/UX-F72MD

1-5

UX-F70MD/UX-F72MD

Disassembly method

Removing the rear cover

(See Fig.1 and 2)

Remove the seven screws A on the back of the body.

Remove the two screws B on the bottom of the body.

Unlock the speaker terminal and the antenna terminal, then remove the rear cover backward with releasing the hooks.

Removing the side panels

(See Fig.3 to 5)

Prior to performing the following procedure, remove the rear cover.

Rear cover

Antenna terminal

Side panel (R)

Speaker terminal

Fig.1

(Bottom)

Rear cover

Remove the two screws C attaching the side panels on the bottom of the body.

Remove each side panel backward while releasing the eight joints a as shown in Fig.4 and 5.

Joint a

Side panel (L)

Fig.2

Side panel (R)

Side panel (L)

Fig.3

Joint a

1-6

Side panel (L)

Fig.5

Side panel (R)

Fig.4

Removing the cassette mechanism assembly section (See Fig.6 and 7)

UX-F70MD/UX-F72MD

Cassette mechanism assembly

Prior to performing the following procedure, remove the rear cover and the side panels.

Remove the two screw D on each side of the body.

Release the joint b on each side of the body and remove the cassette mechanism assembly section in the direction of the arrow.

Disconnect the card wires from connector CN705, CN743 and CN744 on the system control board on the left side of the body.

Removing the fan assembly (See Fig.6)

Prior to performing the following procedure, remove the rear panel and the right side panel.

Disconnect the wire from connector CN907 on the main board on the right side of the body.

Joint b

Fan assembly

CN744

CN743

Main board

CN907

Fig.6

Cassette mechanism assembly

CN705

Joint b

Remove the two screws E attaching the fan assembly.

Removing the MD mechanism assembly section (See Fig.8)

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section and the fan assembly.

Disconnect the card wire from connector CN721 on the system control board.

Disconnect the card wire from connector CN522 on the underside of the MD mechanism assembly section.

Remove the four screws F and the MD mechanism assembly section upward.

System control board

System control board CN721

Fig.7

MD mechanism assembly

CN522

Fig.8

Front panel

1-7

UX-F70MD/UX-F72MD

Removing the system control board

(See Fig.9)

Prior to performing the following procedure, remove the rear cover, the side panels and the cassette mechanism assembly section.

Remove the screw G on the left side of the body.

Disconnect the card wire from connector CN701 and CN721on the system control board.

Disconnect connector CN709, CN711 and CN712 on the system control board from the body outward.

Disconnect the card wire from connector CN704 on the underside of the system control board.

System control board

CN712

CN711

CN701

CN721

CN709

Removing the tuner board (See Fig.10)

Prior to performing the following procedure, remove the rear cover and the right side panel.

Disconnect the card wire from connector CN1 on the tuner board on the right side of the body.

Remove the screw H and remove the tuner board upward while disengaging the three joint c.

CN704

CN1

Fig.9

Tuner board

Joint c

1-8

Fig.10

UX-F70MD/UX-F72MD

Removing the front panel assembly

(See Fig.11 and 12)

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section and the system control board.

Release the two joints d on the lower right and left sides of the front panel assembly, then remove the front panel assembly toward the front.

Front panel assembly

Joint d

Fig.11

Front panel assembly

Removing the headphone jack board

(See Fig.13 and 14)

Prior to performing the following rear cover, the side panels, the cassette mechanism assembly section, the system control board and the front panel assembly section.

Disconnect the wire from connector CN804 on the main board.

Remove the plastic rivet fixing the headphone jack board.

Joint d

Fig.12

Main board

CN804

Headphone jack board

Fig.13

Plastic rivet

Headphone jack board

Fig.14

1-9

UX-F70MD/UX-F72MD

Removing the main board / the heat sink

(See Fig.15 to 17)

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section, the system control board and the MD mechanism assembly section.

Remove the screw I attaching the main board.

Remove the screw H attaching the grounding terminal extending from the main board.

Disconnect the wire from connector CN804 on the main board.

Disconnect connector CN805 on the main board from the AC jack board while pulling out it. Remove the main board in the direction of the arrow and disconnect the wire from connector CN803 on the reverse side of the main board.

Remove the three screws J attaching the heat sink on the reverse side of the main board.

Main board

CN805

CN803

CN804

AC jack board

Fig.15

Removing the AC jack board

(See Fig.18 and 19)

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section, the system control board, the MD mechanism assembly section and the main board / the tuner board.

Disconnect the wire from connector CN809 on the AC jack board.

Remove the screw K and screw L attaching the AC jack board.

AC jack board

CN804

Heat sink

Power transformer assembly

Heat sink

Fig.16

Main board

Fig.17

CN809

1-10

AC jack board

CN809

Fig.19

Fig.18

UX-F70MD/UX-F72MD

Removing the power transformer assembly (See Fig.20)

Disconnect the wire from connector CN809 on the AC jack board.

Cut off the band setting the wire on the CD mechanism cover.

Remove the four screws M attaching the power transformer assembly.

Removing the CD mechanism assembly

(See Fig.21 to 23)

Power transformer

assembly

CD mechanism cover

Band

CD mechanism cover

Fig.20

AC jack board

CD mechanism assembly

CN809

Band

Notch

Headphone

jack board

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section, the system control board, the front panel assembly section, the MD mechanism assembly section, the main board / the tuner board and the AC jack board.

Cut off the band setting the wire on CD mechanism cover.

Release the wire extending from the headphone jack board from the three notches of the CD mechanism cover on the left side of the body.

Remove the four screws N on the left and right side of the CD mechanism cover. Then remove the CD mechanism cover upward.

Remove the three screws O attaching the CD mechanism assembly.

Notches

Fig.21

CD mechanism cover

CD mechanism assembly

Band

Fig.22

CD mechanism assembly

Fig.23

1-11

UX-F70MD/UX-F72MD

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section, the fan assembly and the MD mechanism assembly section.

Removing the MD mechanism assembly

(See Fig.24 to 26)

Remove the four screws P attaching the brackets (1) and (2) on the left and right side of the MD mechanism assembly.

Disconnect the card wire from connector CN521 on the MD mechanism board.

Remove the MD mechanism bottom cover downward.

MD mechanism assembly

brackets (1)

Fig.24

MD mechanism assembly

CN521

brackets (2)

Fig.25

MD mechanism assembly

MD mechanism bottom cover

1-12

Fig.26

UX-F70MD/UX-F72MD

Prior to performing the following procedure, remove the rear cover, the side panels, the cassette mechanism assembly section, the system control board and the front panel assembly section.

Removing the relay board (See Fig. 27)

Disconnect the wire from connector CN906, CN907

1. and the card wire from CN908 on the relay board respectively.

Remove the two screws Q.

Removing the drive motor assembly

(See Fig.28)

Prior to performing the following procedure, remove the relay board.

Remove the four screws R attaching the drive motor assembly.

CN907

Drive motor

assembly

Drive motor assembly

CN908

Fig.27

Door switch board

Relay board

CN906

Removing the belt and the drive motor

(See Fig.29)

REFERENCE:

Remove the two screws S attaching the plate.

Remove the belt from the two pulleys.

Remove the two screws T attaching the drive motor.

REFERENCE:

The belt and the drive motor can be removed respectively without removing the drive motor assembly from the front panel section.

When removing the drive motor only, remove the belt from the drive motor pulleys in advance.

Drive motor

Fig.28

Belt

Fig.29

Plate

1-13

UX-F70MD/UX-F72MD

Removing the door switch board

(See Fig.30 and 31)

Prior to performing the following procedure, remove the relay board.

Loosen the screw U attaching the door switch.

Remove the door switch board while releasing it from the joint e.

CAUTION:

When reattaching the door switch board, fit it to the joint e and check the operating state of the switch before tightening the screw U.

Removing the LCD section

(See Fig.32 to 34)

Prior to performing the following procedure, remove the relay board.

Loosen the two screws V attaching the lock lever.

Drive motor assembly

Switch section

Fig.30

Door switch board

Fig.31

Door switch board

Joint e

Push the part f of the lock lever in the direction of the arrow as shown in Fig.33-1 / 33-2 and disengage the LCD section from the front panel assembly.

CAUTION:

Because the LCD may come off, hold it when loosening the screws V.

LCD section

Front panel assembly

Lock lever Lock lever

Front panel assembly

Fig.32

Lock lever f Lock lever f

1-14

Fig.34

Joint f

Fig.33-1 Fig.33-2

UX-F70MD/UX-F72MD

Removing the LCD board assembly

(See Fig.35 to 39)

Prior to performing the following procedure, remove the relay board and the LCD section.

Remove the four screws W attaching the case cover.

Remove the four screws X attaching the LCD panel on the back of the LCD section.

Remove the LCD cover.

Release the joint g and remove the LCD board assembly in the direction of the arrow.

Case cover

Fig.35

LCD section

Joint g

Fig.36

LCD panel

Fig.37

LCD board assembly

LCD cover

Fig.38Fig.39

1-15

UX-F70MD/UX-F72MD

Prior to performing the following procedure, remove the rear cover, the side panels and the cassette mechanism assembly section.

Removing the operation switch board

(See Fig.40)

Remove the seven screws Y attaching the operation switch board on the reverse side of the cassette mechanism assembly.

Cassette amplifier board

Operation switch board

Removing the cassette mechanism assembly (See Fig.41)

Remove the four screws Z on the reverse side of the cassette mechanism assembly.

Fig.40

Cassette mechanism assembly

1-16

Cassette amplifier board

Fig.41

UX-F70MD/UX-F72MD

Disassembly method

Removing the main board

(See Fig.1 and 2)

Turn over the body and disconnect the card wire from connector CN408 and the flexible wire from CN407 on the main board.

Remove the two screws A attaching the main board. Slide the main board in the direction of the arrow to release the two joints a with the single flame.

Solder part b on the pickup in the body. Disconnect the flexible harness from connector CN321 and CN451 on the underside of the main board. Then remove the main board.

(Bottom)

Main board

CN408

CN407

Joint b Joint b

Fig.1

Main board

CN451

CN321

Removing the mechanism cover

(See Fig.3)

Remove the four screws B on both sides of the body.

Move the mechanism cover toward the front to disengage the front hook of the mechanism cover from the internal loading assembly (Joint c). Then remove the mechanism cover upward.

Fook

Joint c

Pickup

Fig.2

Fig.3

Solder part b

Mechanism cover

1-17

UX-F70MD/UX-F72MD

Removing the head lifter (See Fig.4 to 6)

Move the head lifter on top of the body in the direction of the arrow and turn around.

Detach the spring from the hook of the body. Remove the head lifter with the spring.

If necessary, remove the spring from the head lifter.

Head lifter

Fig.5

Head lifter

Fig.4

Spring

Removing the head assembly (See Fig.7)

Remove the screw C on the upper side of the body. Remove the head assembly while pulling the flexible harness from the body.

Head lifter

Spring

Fig.6

Head assembly

1-18

Fig.7

Removing the Loading assembly

(See Fig.8 and 9)

Ref:

The loading assembly, the traverse mechanism assembly and the single flame will be removable after removing the loading assembly from the body.

UX-F70MD/UX-F72MD

Prior to performing the following procedure, remove the main board, the mechanism cover, the head lifter and the head assembly.

Remove the three screws D on the upper side of the body.

Move the loading assembly forward to disengage it from the traverse mechanism assembly (Joint d). Then remove it upward.

Remove the traverse mechanism assembly from the single flame.

Joint d

Loading assembly

Fig.8

Loading assembly

Fig.9

Traverse mechanism

assembly

Single flame

1-19

UX-F70MD/UX-F72MD

Slide base (R)

Removing the slide base (L) / (R)

(See Fig.10)

Remove the two screws E on the upper side of the loading assembly.

Remove the slide base (L) outward. (Release it from the joint bosses E.)

Remove the slide base (R) outward.

Removing the loading mechanism assembly (See Fig.11)

Detach the loading mechanism assembly upward to release the four pins on both sides from the loading motor, paying attention to the part e of the loading mechanism base.

Slide base (L)

Fig.10

Part e

Loading mechanism assembly

Removing the loading motor

(See Fig.12 and 13)

Disconnect the harnesses from the wire holder and from connector CN612 on the cam switch board.

Remove the screw F attaching the loading motor and release the joint f.

Remove the belt from the loading motor assembly.

Remove the two screws G attaching the loading motor.

Removing the cam gear and the cam switch board (See Fig.12)

Loading mechanism

assembly

Loading motor assembly

Joint f

CN612

Loading mechanism base

Fig.11

Wire holder

Cam switch board

Slit washer

Cam gear

Fig.12

Loading motor

Remove the slit washer attaching the cam gear and pull out the cam gear.

Disconnect the harness from the wire holder and from connector CN612 on the cam switch board.

Remove the two screws H and the clamp. Remove the cam switch board.

1-20

Belt

Fig.13

Removing the cartridge holder assembly

(See Fig.14 and 15)

UX-F70MD/UX-F72MD

Remove the two screws I on the upper side of the loading assembly.

Removing the slide bar and the eject bar

(See Fig.14 and 15)

Prior to performing the following procedure, remove the cartridge holder assembly.

Slide bar

Cartridge holder assembly

Eject bar

Part g

Fig.14

Remove the slide bar upward.

Move the eject bar outward until it stops as shown in Fig.14. Push the convex part g on the bottom of the body and remove the eject bar from the chassis.

Slide bar

Eject bar

UD base

Cartridge holder assembly

Fig.15

1-21

UX-F70MD/UX-F72MD

Removing the Insulators (See Fig.16)

Disengage the four insulators from the notches of the traverse mechanism chassis.

Removing the pickup unit (See Fig.17)

Turn over the traverse mechanism assembly and remove the screw J attaching the shaft holder (F).

Move the shaft inward and remove it from the shaft holder (R).

Pickup unit

Insulators

Traverse machanism chassis

Fig.16

Joint h

Pickup guide

Pickup unit

Insulators

Detach the shaft side of the pickup unit upward and release the joint h with the pickup guide. Then remove the pickup unit with the shaft.

Removing the pickup (See Fig.18)

Draw out the shaft from the pickup.

Remove the two screws K attaching the rack spring.

Shaft holder (F)

Rack spring

Shaft holder (R)

Fig.17

Pickup

1-22

Shaft

Fig.18

Removing the feed motor assembly

(See Fig.19-1, 19-2)

It is not necessary to remove the pickup unit.

For the white and black harnesses extending from the feed motor assembly, unsolder the soldering i on the traverse mechanism board.

UX-F70MD/UX-F72MD

Traberse mechanism board Soldering j

Remove the two screws L attaching the feed motor assembly.

Remove the two screws N attaching the feed motor bracket.

Removing the traverse mechanism board (See Fig.19-1)

Prior to performing procedure, remove the feed motor assembly.

For the red and black harnesses extending from the spindle motor, unsolder the soldering j on the traverse mechanism board.

Soldering i

Feed motor assembly

Fig.19-1

Feed motor

Feed motor bracket

Remove the screw M attaching the traverse mechanism board.

Fig.19-2

1-23

UX-F70MD/UX-F72MD

Reattach the eject bar to the UD base.

(Fig.15 and 20)

Reattach the slide bar to the loading mechanism chassis while fitting the boss marked k to the eject bar slot. (Fig.20)

Slide the slide bar and the eject bar in the direction of the arrow in Fig.20 and reattach the cartridge holder assembly using the two screws I.

(Fig.20 and 21)

ATTENTION:

Make sure the pin of the eject lever marked l is fitted to the slot of the eject bar marked m at the bottom of the loading mechanism chassis after moving the eject lever and the loading slider of the cartridge holder assembly in the direction of the arrow.

(Refer to Fig.21)

Slide bar

Cam switch board

Point marked

Cam switch boss

Ditch

UD base

Eject bar

Fig.20

1-24

UD base (Bottom)

Cartridge holder assembly

Ditch m

Loading slider

Eject lever

Fig.21

Reattach the wire holder to the UD base while engaging the UD base hook marked u to the wire holder slot marked t (At the same time, the boss on the reverse side of the wire holder is fitted to the UD base round hole).

Reattach the cam switch board using the two screws H. (Fig.22)

Turn the cam switch to bring the boss to the point marked on the cam switch board. Reattach the cam gear using a slit washer while fitting the cam gear slot to the cam switch boss. (Fig.22)

UX-F70MD/UX-F72MD

ATTENTION:

When reattaching the cam gear, the cam switch boss should be fitted to the cam gear slot, and the triangle mark of the cam gear should be aligned to the hole of the eject bar as shown in Fig.22.

Reattach the loading motor assembly, using the screw F. Connect the harness extending from the loading motor to connector CN612 on the switch board and fix it with the wire holder. (Fig.22)

Slide bar CN612

Loading motor assembly

Point marked

Boss

Cam switch

Cam switch board

Eject lever

Fig.22

Cam gear

Cam gear (Triangle mark)

Eject lever

1-25

UX-F70MD/UX-F72MD

Reattach the UD base while engaging the four pins on both sides of the UD base to the notches of the loading mechanism base and placing the edge (marked e’) of the cartridge holder assembly under the hook e of the loading mechanism base. (Fig.23)

Reattach the slide base (R) while fitting the two pins on another side of the UD base to the slots of the slide base (R). (Fig.24)

ATTENTION:

10.

Reattach the slide base (L) on the slide base (R) while fitting the two pins on another side of the UD base to the slots of the slide base (L) (Fig.25). Make sure the two slots of the slide base (L) are fitted to the two bosses marked E’ and tighten the two screws E. (Fig.26)

Ref:

To expedite the work, bring up the UD base slightly when fitting each pin to the appropriate notch.

Fit the part v of the slide base (R) to the part w on the inward side of the cam gear rib. (Fig.25)

Hook e

Hook e'

Loading mechanism base

Fig.23

Slide base (R)

Part v

Slide base (L)

Part w

Fig.24

Slide base (L)Slide base (R)

Slide base (R)

Cam gear

Part v

Part w

1-26

Fig.25Fig.26

UX-F70MD/UX-F72MD

Removing the Recording, Playback / Erasing Head (Refer to Figs. 1 to 3.)

1. Shifting the trigger arm seen in the right side of the head mount in the arrow-marked direction, turn the flywheel (R) counterclockwise until the head mount clicks while moving frontwards. (See Fig. 1.)

2. Turn the flywheel (R) counterclockwise. The playback head accordingly turns counterclockwise from the position shown in Fig. 2 to that in Fig. 3.

3. Leaving the playback head in the position shown in Fig. 3, disconnect the flexible wire coming from the playback head from the connector CN31 on the head amplifier & mechanism control P.C. board.

4. Remove the flexible wire from the hook b of the chassis base.

5. Remove the spring a from the back of the head.

Cassette mechanism

Head mount

Head (REC, PB/Erasing)

Flexible wire

Flywheel (R)

Trigger arm

Fig. 1

Spring a

Trigger arm

6. Loosen the reversing azimuth screw A that fastens the head.

7. Remove the recording, playback/erasing head from the front side (head side) of the head mount.

Reinstalling the Recording, Playback / Erasing Head

1. Install the recording, playback/erasing head from the front side of the head mount as shown in Fig. 3.

2. Tighten the reversing azimuth screw A.

3. Install the spring a from the back of the head.

4. Set the flexible wire at the hook b of the chassis base.

5. Connect the flexible wire coming from the head to the connector CN31 on the head amplifier & mechanism control P.C. board.

Head amp. & mechanism control P.C. board

Head (REC, PB/Erasing)

Spring a

Flexible wire

Hook b

Flywheel (R)

Fig. 2

Reversing azimuth screw A

Head mount

Head amp. & mechanism control P.C. board

Fig. 3

1-27

UX-F70MD/UX-F72MD

Removing the Head Amplifier & Mechanism Control P.C. Board (Refer to Figs. 4 and 5.)

1. Disconnect the flexible wire from the connector CN31 on the head amplifier & mechanism control P.C. board mounted on the back of the cassette mechanism assembly.

2. Remove the three screws B fastening the head amplifier & mechanism control P.C. board.

3. Disconnect the connector CN32 of the head amplifier & mechanism control P.C. board from the connector CN1 on the reel pulse P.C. board.

Note: Remove the 4-pin parallel wire soldered to the

main motor depending on the situation.

Removing the Main Motor Assembly (Refer to Figs. 4 to 7.)

The main motor assembly can be removed without removal of the head amplifier & mechanism control P.C. board.

Head amp. & mechanism control P.C. board

Flexible P.C. board 4-pin parallel wire

Fig. 4

Main motor assembly

Capstan belt

Main motor assembly

Belt

Main motor assembly

1. Remove the two screws C fastening the main motor assembly.

2. Lifting the main motor assembly slightly upwards, disengage the capstan belt from the motor pulley.

Note: Be careful not to soil the capstan belt with grease

or the like. When reinstalling the main motor assembly, refer to Fig. 6 and Fig. 7 for engaging the capstan belt.

Capstan belt

Main motor assembly

Motor pulley

Fig. 5

Main motor assembly

Motor pulley

Fig. 6

1-28

Flywheel

Capstan belt

Motor pulley

Fig. 7

UX-F70MD/UX-F72MD

Removing the Flywheel (Refer to Figs. 8 and 9.)

Remove the head amplifier & mechanism control P.C. board. Remove the main motor assembly.

1. Remove the slit washers c and d that fasten the capstan shafts (L) and (R) from the front side of the cassette mechanism assembly, and then draw out the flywheels (L) and (R) from the back side of the cassette mechanism assembly in the arrow-marked direction for removing them.

Removing the Reel Pulse P.C. Board / Solenoid (Refer to Fig. 10.)

Remove the head amplifier & mechanism control P.C. board. Remove the main motor assembly.

1. Remove the screw D fastening the reel pulse P.C. board.

Flywheel (R)

Capstan shaft (R)

Slit washer d

Fig. 8

Flywheel (L)

Capstan shaft (L)

Slit washer c

2. Disengage the five hooks e that retain the reel pulse P.C. board by pressing each in the arrowmarked direction.

3. Disengage the two hooks f that retain the solenoid by pressing each from the front side of the cassette mechanism assembly in the arrow-marked direction.

Note: When reinstalling the reel pulse P.C. board and

solenoid, make sure that the hook g of the solenoid is properly engaged.

Hook e

Hook f

Hook e

Flywheel (R)

Flywheel (L)

Fig. 9

Hook e

Reel pulse P.C. board

1-29

UX-F70MD/UX-F72MD

Disassembly Method

Removing the CL. Base Assembly and Tray (Refer to Figs. 1 to 5.)

1. Remove the two screws A fastening the CL. base assembly from the top of the CD mechanism assembly.

CL. base assembly

Hook a

2. Move the CL. base assembly diagonally upwards as indicated by the arrow to release it from the two hooks a.

3. Turn the idle gear in the arrow-marked direction from the upper side of the CD mechanism assembly. Accordingly, the TRAMECHA assembly moves downwards.

Note: When drawing out the tray, shift down the

TRAMECHA assembly to the position where the tray does not contact the T-T assembly of the TRAMECHA assembly.

4. Draw out the tray frontwards for removing it.

Note: When reinstalling the tray: Turn the idle gear so that the part b of the

tray gear is positioned in the part c shown in Fig. 4. (Eject position)

Engage the right and left hooks d and e of

the tray with the right and left grooves of the TRAMECHA assembly respectively for retaining the tray.

Fig. 1

Idle gear

TRAMECHA assembly

Tray

Fig. 2

TRAMECHA assembly

1-30

Hook d

Idle gear

Tray gear

Hook d

Tray

Tray gear

Idle gear

Tray

Fig. 3

Part c

Part b

Fig. 4Fig. 5

+ 82 hidden pages

JVC UXF-70-MD, UXF-72-MD Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual