JVC UXL-30, UXL-40 Service manual

SERVICE MANUAL

MICRO COMPONENT SYSTEM

UX-L40/UX-L30

UX-L40/UX-L30

UX-L40/UX-L30

BASS

SET

CD TAPE

CD

REV.MODEFM MODE

PRGM RANDOM REPEAT

RM-SUXL40U REMOTE CONTROL

UP

DOWN

SURROUNDAHB PRO

STANDBY / ON

COMPACT

DIGITAL AUDIO

STANDBY/ON

DISPLAY

CLOCK
/TIMER

SLEEP

TREBLE

CANCEL

FM/AM

AUX/MD

AUTO
PRESET

DIMMER

VOLUME

PHONES

SP-UXL40 SP-UXL40CA-UXL40

CD-R/RW PLAYBACK

REC SURROND AHB PRO

CLOCK/TIMER AUX/MD

MICRO COMPONENT SYSTEM UX-L40

VOLUME

+–

CD TAPE

FM/AM

UP

DOWN

BASS TREBLE

AUTO REVERSE

STANDBY/ON

1

3

2

4

5

6

DISPLAY

CLOCK

7

9

8

PUSH
OPEN

10

UP

BASS

SET

DOWN

CD/TAPE FM/AM AUX/MD

CD

REV.MODEFM MODE

PRGM RANDOM REPEAT

RM-SUXL30U REMOTE CONTROL

/TIMER

+10

SLEEP

TREBLE

CANCEL

AUTO
PRESET

AHB PRO

DIMMER

VOLUME

SP-UXL30 SP-UXL30CA-UXL30

UX-L40

Area Suffix

US ----------------- Singapore
UP ----------------------- Korea
UW ------- Brazil,Mexico,Peru

STANDBY / ON

COMPACT

DIGITAL AUDIO

PHONES

CD-R/RW PLAYBACK

REC REV. MODE AHB PRO

CLOCK/TIMER AUX/MD

MICRO COMPONENT SYSTEM UX-L30

VOLUME

+–

CD TAPE

FM/AM

UP

DOWN

BASS TREBLE

AUTO REVERSE

PUSH
OPEN

UX-L30

Area Suffix

US ----------------- Singapore
UP ----------------------- Korea
UW ------- Brazil,Mexico,Peru
UJ -------------------- U.S.Military

Contents

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

1-2
1-3
1-4
1-5
1-19

Flow of functional operation
until TOC read (CD)
Maintenance of laser pickup
Replacement of laser pickup
Description of major ICs

COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD.

1-24
1-25
1-25
1-26~35

No.21105

Jul. 2002

1-1

UX-L40/UX-L30

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 each exposed 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.

!

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.

In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the
parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the " "
mark nearby are critical for safety.

(This regulation does not correspond to J and C version.)

1-2

UX-L40/UX-L30

Preventing static electricity

1.Grounding to prevent damage by 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.

2.About the earth processing for the destruction prevention by static electricity

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

2-1 Ground the workbench

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.

2-2 Ground yourself

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

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.

4.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

Attention when traverse unit is decomposed

*Please refer to "Disassembly method" in the text for pick-up and how to
detach the substrate.

Shorting round

1.Solder is put up before the card wire is removed from connector on
the CD substrate as shown in Figure.
(When the wire is removed without putting up solder, the CD pick-up
assembly might destroy.)

2.Please remove solder after connecting the card wire with
when you install picking up in the substrate.

Flexible wire

Shorting round

CN601 on
mechanism
board

1-3

UX-L40/UX-L30

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
laserradiation and is equipped with safety switches
whichprevent 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.

CAUTION

!

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

1-4

Disassembly method

<Main body>

Removing the Metal cover
(See Fig.1 to 3)

UX-L40/UX-L30

A

1.

Remove the six screws A on the back of the main
body.

2.

Remove the screw B on each side and remove the
cover in the direction of the arrow.

A

A

Fig.1

B

B

Fig.2Fig.3

1-5

UX-L40/UX-L30

Removing the Rear cover
(See Fig.4)

Remove the metal cover.

1.

Remove the two screws C retaining the rear cover.

Removing the Rear panel
(See Fig.5)

Remove the metal cover and the rear cover.

C

C

Fig.4

1.

Remove the twelve screws D retaining the rear
panel. Release the two joints a on the rear side and
the joint b on each side.

D

D

D

D

a

DD

bb

Fig.5

1-6

Removing the Tuner board

(See Fig.6)

Remove the metal cover.

1.

Disconnect the card wire from connector CN1 on the
tuner board.

UX-L40/UX-L30

2.

Remove the two screws E on the rear side and the
screw F on the side.

Removing the Optical digital board
(See Fig.7)

Remove the metal cover.

F

E

CN1

Tuner board

Fig.6

Optical digital board

H

1.

Disconnect the shield wire from connector CN905 on
the optical digital board.

2.

Remove the screw G on the rear side and the screw
H on the upper side.

G

CN905

Fig.7

1-7

UX-L40/UX-L30

Removing the CD-R/RW mechanism
assembly (See Fig.8)

Remove the metal cover, the rear cover, the rear
panel, the tuner board and the optical digital board.

1.

Disconnect the card wire from connector CN903 and
CN904 on the main board.

2.

Pull the joint c in the direction of the arrow and
remove the CD-R/RW mechanism assembly
backward while releasing the joint d.

CD-R/RW mechanism
assembly

c

d

CN903

CN904

Fig.8

Main board

1-8

UX-L40/UX-L30

Removing the Main board/ the Heat sink
board (See Fig.9 to 11)

Remove the metal cover, the rear cover and the rear
panel.

1.

Disconnect the card wire from connector CN902,
CN903, CN904 and CN905 on the main board and
remove the CD-R/RW mechanism assembly.

REFERENCE:

2.

Remove the two screws I to remove the main board.

3.

Disconnect the card wire from connector CN931,
CN935, CN933, CN934, CN913, CN901, CN900 and
CN917 on the main board.

4.

Remove the band f and disconnect the card wire
from connector CN951 on the power transformer
assembly. Remove the main board / the heat sink
board from the body.

Refer to the method of removing the
CD-R/RW mechanism assembly and
Fig.8.

CD-R/RW mechanism assembly

CN905

CN902 CN904

CN903

e

CN915

I

CN916

I

Main board

Fig.9

5.

Release the joint e of the main board and disconnect
connector CN944 and CN945 of the heat sink board
from connector CN915 and CN916 of the main board
respectively.

Main board

Heat sink board

CN944

CN945

CN933

CN934

CN913

CN901

CN931

CN935

CN951

Main board

Heat sink board

CN900

CN917

f

Power transformer
assembly

Fig.10Fig.11

1-9

UX-L40/UX-L30

Removing the Power transformer
assembly (See Fig.12)

Remove the metal cover, the rear cover, the rear
panel, the CD-R/RW mechanism assembly and the
main board.

Disconnect the power cord from connector J1000 on

1.
the power transformer assembly.

Remove the four screws J.

2.

J

JJ

J1000
Power transformer
assembly

Fig.12

1-10

UX-L40/UX-L30

Removing the Front panel assembly
(See Fig.13 to 16)

Remove the metal cover.

Remove the screw K on each side. Pull the joint h

1.
on both sides and lift the front panel assembly to
release the joint g.

Disconnect connector CN931, CN935, CN933 and

2.
CN934 on the main board.

Disconnect the card wire from connector CN33 and

3.
CN34 on the cassette mechanism board.

Front panel
assembly

h

Main board

g

K

Fig.13

g

Front panel
assembly

CN34 CN33

CN935 CN931

Fig.14

g

CN933
CN934

h

K

Cassette mechanism
assembly

Cassette mechanism
board

hh

Fig.15Fig.16

1-11

UX-L40/UX-L30

Removing the Phones board
(See Fig.17)

Prior to performing the following procedure, remove
the metal cover and the front panel assembly.

1.

Disconnect connector CN913 on the main board.

Main board

CN913

Phones board

Fig.17

Removing the Cassette mechanism
assembly (See Fig.18)

Prior to performing the following procedure, remove
the metal cover and the front panel assembly.

1.

Remove the four screws L retaining the cassette
mechanism assembly.

L

L

Cassette mechanism
assembly

Fig.18

1-12

Removing the Control board
(See Fig.19)

Prior to performing the following procedure, remove
the metal cover and the front panel assembly.

1.

Remove the seven screws M to remove the control
board.

UX-L40/UX-L30

M

Removing the Volume board
(See Fig.20 and 21)

Prior to performing the following procedure, remove
the metal cover and the front panel assembly.

Control board

N

M

Fig.19

N

1.

Remove the four screws N attaching the volume
panel on the front panel assembly.

2.

Remove the six screws O attaching the volume
board on the volume panel, and remove the volume
board.

O

Fig.20

Volume panel

Volume board

O

O

Fig.21

1-13

UX-L40/UX-L30

<CD mechanism assembly section>

Removing the CD servo board

(See Fig.1, 2)

CAUTION:

1.

Remove the two screws A on the bottom of the
loading base.

2.

Disconnect the card wire from connector CN606 on
the CD servo board. Turn over the CD servo board
as shown in Fig.2 and put aside temporarily.

3.

Solder the shorting round on the pickup board in the
CD pickup section.

4.

Disconnect the card wire from connector CN601 and
the wire from CN801 on the CD servo board.

CAUTION:

Solder the shorting round before disconnecting
the card wire extending from the pickup. If
you do not follow this instruction, the pickup
may be damaged.

When reassembling, make sure to unsolder
the shorting round after connecting the card
wire from the pickup to the connector.

CD servo board

CN601

CN606

CN801

A

Fig.1

CD servo board

CN801

CN601

1-14

Shorting round

Pickup board

CD pickup

CD pickup

Shorting round

(Soldering)

Fig.2

UX-L40/UX-L30

Removing the clamper base / tray

(See Fig.3 ~ 5)

1.

Bring up the fitting in the direction of the arrow to
release the three joints a.

2.

On the front side of the body, move the cam plate
lever to the center.

3.

Remove the stopper screw B and pull out the tray
toward the front.

4.

Remove the four screws C attaching the clamper
base.

5.

From the rear side, remove the clamper base
upward.

Tray

Joint a

Fig.3

Fitting

Joint a

Tray

C

B

Clamper

C

Cam plate

(Lever)

Fig.4

Clamper base

C

Tray

Fig.5

1-15

UX-L40/UX-L30

Removing the CD mechanism assembly

(See Fig.6, 7)

Prior to performing the following procedure, remove
the clamper base / tray and the CD servo board.

1.

Remove the screw D attaching the CD mechanism
assembly.

2.

Move the CD mechanism assembly backward to
release the two joints b of the CD base on the front
side.

CAUTION:

When reassembling, fit the front part of the
CD mechanism assembly to the two
chassis joints b and attach the four
dampers correctly.

CD mechanism assembly

damper

damper

CD mechanism assembly

D

damper

damper

b

Fig.6

D

CD base

b

Fig.7

1-16

Removing the loading motor / loading
motor board (See Fig.8, 9)

Prior to performing the following procedure, remove
the clamper base / tray and the CD servo board.

1.

From upside of the loading base, remove the belt
from the motor pulley.

2.

Remove the two screws E attaching the loading
motor.

3.

At the bottom of the body, release the three joints c
outward and pull out the loading motor board from
the shaft. The loading motor comes off with the
loading board.

4.

Unsolder the two soldered points d on the loading
motor board and remove the loading motor.

REFERENCE:

When removing the loading motor board
only, unsolder the two soldering d on the
loading motor and release the three joints c.

Soldering d

Loading motor

Loading motor

Belt

E

Fig.8

c

Loading motor board

UX-L40/UX-L30

E

Motor pulley

c

Fig.9

1-17

UX-L40/UX-L30

Removing the C.D. gear (1), (2) and (3)

(See Fig.10 ~ 13)

Prior to performing the following procedure, remove
the CD servo board.

1.

Remove the two screws F attaching the CD base on
the bottom of the loading base.

2.

Remove the rear part of the CD base upward and
pull out the shaft e of the CD base from the camplate
on the front side of the loading base.

REFERENCE:

3.

Remove the leaf spring on the upside of the loading
base.

4.

Remove the screw G attaching the cam plate fitting.

5.

Remove the screw H and the cam plate upward.

The CD mechanism assemly comes off
with the CD base.

FF

e

CD base

(Bottom)

Loading base

Fig.10

CD mechanism assembly

F

6.

Remove the belt from the C.D. gear (1).

7.

Pull out the C.D. gear (1), (2) and (3) respectively.

Cam plate fitting

G

Cam plate

H

F

CD base

Loading base

Fig.11

C.D. gear (3)

Belt

1-18

Spring

C.D. gear (2)

C.D. gear (1)

Fig.13Fig.12

Adjustment method

UX-L40/UX-L30

Measurement Instruments Required for

Adjustment

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

2. Attenuator impedance : 600

3. Electronic voltmeter

4. Distortion meter

5. Frequency counter

6. Wow & flutter meter

7. Test tape
VT703L : Head azimuth
VT712 : Tape speed and running unevenness
(3kHz)
VT724 : Reference level (1kHz)

8. Blank tape
TYPE
TYPE : AC-514

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

10. Test disc: CTS-1000

Measurement conditions

Power supply voltage
AC110V/127V/220V/230V 240V , adjustable
Reference output : Speaker : 0.775V/4
: Headphone : 0.077V/32
Reference frequency and
input level ------------------------------ 1kHz, AUX : -8dBs
Measurement output terminal ------- at Speaker J3002
Load resistance --------------------------- 4

Radio Input signal

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

at an oscillation frequency of

: AC-225

Tuner section

FM tuning range: 87.5MHz 108.00MHz
AM tuning range:

At 9kHz intervals: 531kHz 1,710kHz

At 10kHz intervals: 530kHz 1,710kHz
Voltage applied to tuner +B : DC5.7V
VT : DC 12V
Reference measurement
output 26.1mV(0.28V)/3
Input positions AM : Standard loop antenna
FM : TP1 (hot) and TP2 (GND)

Standard measurement position of volume

Function switch to Tape
Beat cut switch to Cut
Super Bass/Active hyper Bass to OFF
Bass Treble to Center
Adjustment of main volume to reference output
VOL : 28

Precautions for measurement

1. Apply 30pF and 33k
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).

to the IF sweeper output

1-19

UX-L40/UX-L30

<<

Arrangement of Adjusting Position

>>

Cassette mechanism section

Head azimuth
adjusting screw
(Forward side)

Cassette AMP board

VR37

C308

R314

MOTOR SPEED

VR37

L301

B155

VR31

BIAS ADJ

VR31

Head azimuth
adjusting screw
(Reverse side)

MB

PBRAGPBL

RECRAGRECL

MS

SW8V

MG

1

CN34

C307

R313

C310

R315

C314

Q302

R327

C317

C319

C221

B112

C313

C121

L303

C316

R310

R335

B198

R353

Q305

C106

Q103

R305

R303

R122

Q101

C103

B163

Q321

R221

10

B156

C303

R115

B157

R108

R101

C113
R110
R109

R102

C110

C104

R301

R121

1

C108

C107

9

B151

R112

R111

C102

R107

B152

C302

R103
1

C301

C111

C306

B164

Cassette mechanism section (Back side)

Head azimuth
adjusting screw
(Forward side)

Playback/Recording &
eraser head

R304

C109

B158

8

B106

C101

6

B166

R116

R212
R211
C211

R216

9

IC32

9

C201

B101

B109B108

C209

CN33

R342

C213
R210
R209

C207

B159

16

B102

R341

C208

R207

1

B110

CN31

B200

1

R205

R208

B160

R343

R340

R105
C105

C206

R345

NC

C305

R201

1IC31

TAP

B113

C304

RRE

C202
C210

Q331

C375

C205

C203

B161

R215

R339
C334

R106

R206

5VMGSOL

R204

R203

B153

R104

R222

C204

B168

PHO

R202

C333

C332

R375

Q201

PLA

Q203

C331

Q372

R331

B167

FRE

R371

C376

10

70u

Q375

CN32

R376

R372
R373

B162

C371

16

1

C374

R338

B

E

D375

Q376

B

Q371

E

R337

R336

9

IC33

8

Head azimuth
adjusting screw
(Reverse side)

1-20

Tape Recorder Section

UX-L40/UX-L30

Items

Confirmation
of head angle

Measurement
conditions

Test tape
: VT703L (8kHz)
Measurement output
terminal
: Speaker terminal
Speaker R
(Load resistance: 4 )
: Headphone terminal

Measurement method

1 Playback the test tape VT703L (8kHz)
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.

Confirmation
of tape speed

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

Adjust VR37 so that the frequency counter
reading becomes 2,940~3,090Hz 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
: 2,940 ~
3,090Hz

Adjusting
positions

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

VR37

Items

Difference
between the
forward and
reverse speed

Measurement
conditions

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

Wow & flutter Test tape

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

Measurement method

Standard
Values

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).

6.0Hz or
less

0.25% or
less
(WRMS)

Adjusting
positions

Head azimuth
screw

1-21

UX-L40/UX-L30

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

Standard
Values

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.

AC-225
: 4.20
AC-514
: 4.0 A

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

Adjusting
positions

VR31

A

VR31

2dB

Reference Values for Electrical Function Confirmation Items

Items

Recording
bias
frequency

Measurement
conditions

Forward or reverse

Test tape

: TYPE (AC-514)

Measurement
terminal : BIAS TP on
P.C. board

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.

Eraser
current
(Reference
value)

Forward or reverse

Recording mode
Test tape

: AC-514 to TYPE
and AC-225 to
TYPE
Measurement
terminal : Both of the
eraser head terminals

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

1-22