Sony WE475 - TC Dual Cassette Deck Service Manual

Model Name Using Similar Mechanism TC-WE435

DECK A TCM-230ASR41A
DECK B TCM-230ASR41B

US Model

Canadian Model

AEP Model

UK Model

E Model

Australian Model

STEREO CASSETTE DECK

SPECIFICATIONS

Dolby noise reduction extension manufactured under license
from Dolby Laboratories Licensing Corporation.
HX Pro originated by Bang & Olufsen. “DOLBY”, the double-D
symbol ; and “HX PRO” are tr ademarks of Dolby Laboratories
Licensing Corporation.

TC-WE475

— Continued on next page —

Transport Mechanism Type

Ver 1.0 2001.04

Sony Corporation

Home Audio Company
Shinagawa Tec Service Manual Production Group

9-873-893-11

2001D0900-1
© 2001. 4

SERVICE MANUAL

System

Fast-winding time

Approx.100 sec. (with Sony C-60 cassette)
Signal-to-noise ratio (at peak level and weighted with Dolby
NR off)

55 dB, using Sony TYPE I cassette

57 dB, using Sony TYPE II cassette

58 dB, using Sony TYPE IV cassette
S/N ratio improvement

With Dolby B NR on:

Approx. 5 dB at 1 kHz, 10 dB at 5 kHz

With Dolby C NR on:

Approx. 15 dB at 500 Hz, 20 dB at 1 kHz
Harmonic distortion

0.4% (using Sony TYPE Icassette):

160 nWb/m 315 Hz, 3rd H.D.)

1.8% (using Sony TYPE IV cassette):

250 nWb/m 315 Hz, 3rd H.D.)
Frequency response (DOLBY NR OFF)

30-16,000 Hz (±3 dB, IEC), 20-17,000 Hz

(±6 dB), using Sony TYPE I cassette

30-17,000 Hz (±3 dB, IEC), 20-18,000 Hz

(±6 dB), using Sony TYPE II cassette

30-19,000 Hz (±3 dB, IEC), 20-20,000 Hz

(±6 dB), 30-13,000 Hz (±3 dB, –4dB recording),

using Sony TYPE IV cassette

Wow and flutter

±0.15% W. Peak (IEC)

0.1% W. RMS (NAB)
±0.2% W. Peak (DIN)

Variable pitch range

Approx. –30 to +30 %

Inputs

Line inputs (phono jacks)

sensitivity 0.16 V, input impedance 47 kilohms

Outputs

Line outputs (phono jacks)

rated output level 0.5 V at a load impedance of
47 kilohms, load impedance over 10 kilohms

Headphones (stereo phone jack)

output level 0.25 mW at a load impedance of
32 ohms

2

TC-WE475

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE
WITH MARK 0 ON THE SCHEMATIC DIAGRAMS AND IN THE
PARTS LIST ARE CRITICAL TO SAFE OPERATION. RE­PLACE THESE COMPONENTS WITH SONY PARTS WHOSE
P AR T NUMBERS APPEAR AS SHO WN IN THIS MANUAL OR
IN SUPPLEMENTS PUBLISHED BY SONY.

ATTENTION AU COMPOSANT AYANT RAPPORT

À LA SÉCURITÉ!!

LES COMPOSANTS IDENTIFIÉS P AR UNE MARQUE 0 SUR LES
DIAGRAMMES SCHÉMA TIQ UES ET LA LISTE DES PIÈCES SONT
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIÈCES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.

SAFETY CHECK-OUT

After correcting the original service problem, perform the follow­ing safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs, screws,
and all other exposed metal parts for AC leaka ge. Check leakage as
described below.

LEAKAGE

The AC leakage from any exposed metal part to earth Ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microampers). Leak­age current can be measured by any one of three methods.

1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers’ instructions to use these
instruments.

2. A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a V OM
or battery-operated A C v oltmeter. The “limit” indication is 0.75
V, so analog meters must have an accurate low-voltage scale.
The Simpson 250 and Sanwa SH-63Trd are examples of a pas­sive VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are suitable. (See Fig. A)

Fig. A. Using an AC voltmeter to check AC leakage.

0.15µF

To Exposed Metal
Parts on Set

1.5kΩ

AC
voltmeter
(0.75V)

Earth Ground

General

Power requirements
U.S.A.and Canadian models:

120 V AC, 60Hz

European models:

230 V AC, 50/60Hz

Australian models:

240 V AC, 50/60Hz

Other models:

120/220/230-240 V AC, 50/60Hz
Adjustable with voltage selector

Power consumption

18 watts

Dimensions (w/h/d)

Approx. 430 × 120 × 300 mm

Mass 4.2 kg

Supplied accessories

Audio connecting cords (2)
Control A1II cable (1)*
*Supplied for Canadian models only

Design and specifications are subject to change
without notice.

3

TC-WE475

PA RTS No. MODEL

4-232-514-0s US model
4-232-514-1s CND model
4-232-514-2s AEP model
4-232-514-3s UK model
4-232-514-4s SP model
4-232-514-5s AUS model

MODEL IDENTIFICATION

–Back panel–

Part No.

• Abbreviation
CND : Canadian model
SP : Singapore model
AUS : Australian model

TABLE OF CONTENTS

1. GENERAL .......................................................................... 4

2. DISASSEMBLY

2-1. Case ......................................................................................5

2-2. Front Panel Assy ................................................................... 5

2-3. Cassette Lid Assy (Deck A/B) .............................................. 6

2-4. Mechanism Deck Assy (Deck A/B) ...................................... 6

3. SERVICE MODE .............................................................. 7

4. MECHANICAL ADJUSTMENTS................................. 8

5. ELECTRICAL ADJUSTMENTS ................................. 8

6. DIAGRAMS

6-1. Circuit Boards Location ...................................................... 12

6-2. Printed Wiring Board – MAIN Section –............................ 14

6-3. Schematic Diagram – MAIN (1/4) Section –...................... 15

6-4. Schematic Diagram – MAIN (2/4) Section –...................... 16

6-5. Schematic Diagram – MAIN (3/4) Section –...................... 17

6-6. Schematic Diagram – MAIN (4/4) Section –...................... 18

6-7. Printed Wiring Board – DECK A Section – ........................ 19

6-8. Schematic Diagram – DECK A Section –........................... 19

6-9. Printed Wiring Board – DECK B Section –........................ 19

6-10. Schematic Diagram – DECK B Section –......................... 19

6-11. Schematic Diagram – DISPLAY Section –....................... 20

6-12. Printed Wiring Board – DISPLAY Section – .................... 21

6-13. Schematic Diagram – PANEL Section –........................... 22

6-14. Printed Wiring Board – PANEL Section –........................ 23

6-15. Schematic Diagram – POWER Section – ......................... 24

6-16. Printed Wiring Board – POWER Section – ...................... 25

6-17. IC PIN FUNCTION .......................................................... 26

7. EXPLODED VIEWS

7-1. Case Section ........................................................................ 27

7-2. Chassis Section ................................................................... 28

7-3. Cassette Holder Section ...................................................... 29

7-4. Front Panel Section ............................................................. 30

7-5. Tape Mechanism Section .................................................... 31

8. ELECTRICAL PARTS LIST ........................................ 32

4

TC-WE475

SECTION 1

GENERAL

Front Panel

Location of Parts and Controls

1 POWER button
2 RESET (Deck A) button
3 MEMORY (Deck A) button
4 RESET (Deck B) button
5 MEMORY (Deck B) button
6 AUTO REC LEVEL indicator
7 REC LEVEL knob
8 FADER button
9 ARL button
q; SYNCHRO button
qa PHONES jack
qs HIGH/NOMAL button
qd (AMS) M (Deck B) button
qf H (Deck B) button
qg REC z button
qh A (Eject) (Deck B) button

qj REC MUTING W button
qk h (Deck B) button
ql PAUSE X button
w; x (Deck B) button
wa m (AMS) (Deck B) button
ws (AMS) M (Deck A) button
wd DOLBY NR OFF B/C switch
wf H (Deck A) button
wg h (Deck A) button
wh m (AMS) (Deck A) button
wj A (Eject) (Deck A) button
wk x (Deck A) button
wl PITCH CONTROL knob
e; PITCH CONTROL button
ea DIRECTION MODE switch

• AMS is the abbreviation for Automatic Music Sensor.

1 2 3 4 5 6 7

e;

ea

wj

wl

ql qjwg wd

wf w; qk qhwh

9
0

qa

8

ws qs

qd

qfwk

qg

wa

5

TC-WE475

SECTION 2

DISASSEMBLY

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

2-1. CASE

2-2. FRONT PANEL ASSY

1

screw

(BVTT 3x6)

2

two screws

(case 3 TP2)

3

two screws

(case 3 TP2)

4

case

qs

screw

(BVTP 3x8)

qf

screw

(BVTP 3x8)

qd

screw

(BVTP 3x8)

qg

two screws

(BVTT 3x6)

qj

claw

qh

claw

qk

front panel assy

8

CN301

7

CN401

2

CN807

1

CN5802

3

CN803

4

CNA806

5

flat type wire

(Deck A)

9

CN002

6

flat type wire

(Deck B)

0

screw

(BVTP 3x8)

qa

wire

Set Case

Front Panel Assy Cassette Lid Assy (Deck A/B) Mechanism Deck Assy (Deck A/B)

• The equipment can be removed using the following procedure.

6

TC-WE475

2-3. CASSETTE LID ASSY (DECK A/B)

2-4. MECHANISM DECK ASSY (DECK A/B)

2

four claws

1

Push the EJECT button.

3

cassette lid assy

1

two screws

(BVTP 2.6x8)

3

mechanism deck assy

2

two screws

(BVTP 2.6x8)

7

TC-WE475

RESET 0
MEMORY 1
m (AMS) 2
(AMS) M 3

x Grid check display (*1)
h 4
H 5

DIRECTION MODE switch

g h

s PLAY

RELAY H

A deck side

Button Display

KEY CHECK & DISPLAY CHECK MODE

While pressing the h (A deck) and REC MUTING W buttons with the power off, press the POWER button to turn on the power.
The fluorescent indicator tube displays the number or special message corresponding to the button pressed.
The message displayed differs according to the position of the switch.

SECTION 3

SERVICE MODE

RESET 0
MEMORY 1
HIGH/NOMAL 2
m (AMS) 3
(AMS) M 4

x Segment check display (*2)
h 5
H 6

PAUSE X 7
REC MUTING W 8
REC z 9
FADER A
ARL b
SYNCHRO All lit
DOLBY NR switch

OFF h

B PLAY
C H

B deck side

Button Display

Grit check display (*1)

Segment check display (*2)

RMS

8

TC-WE475

PRECAUTION

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

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

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

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

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

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

Torque Measurement

SECTION 5

ELECTRICAL ADJUSTMENTS

SECTION 4

MECHANICAL ADJUSTMENTS

PRECAUTION

1. The adjustment should be performed in the publication.
(Be sure to male playback adjustment at first.)

2. The adjustments and measurement should be performed for both
L-CH and R-CH.

• Switch position

DOLBY NR switch : OFF
DIRECTION MODE switch : g

• Standard record position :

Deliver the standard input signal le vel to input jack and set the
REC LEVEL knob to obtain the standard output signal level
as follows.

– Record Mode–

0 dBs = 0.775 V

Standard Input Level

Test Mode

1. While pressing the H (DECK A) and REC MUTING W
buttons with the power off, press the ! button to turn on the
power. The fluorescent displa y tube lights up for about one sec­ond, and the test mode is set. The test mode performs the fol­lowing two special functions.

• Playback speed switching function

Pressing the HIGH/NORMAL button switches the playback
speed between standard/double speed.

• Counter RESET & MEMORY function

Resets the counter when recording starts. When rewound with
the m (AMS) button after recording, stops at the point where
recording started.

2. To release the test mode, turn OFF the power switch.

Mode Torque meter Meter reading

Forward

CQ-102C

30 to 65 g • cm

(0.42 to 0.90 oz • inch)

Forward
back
tension

CQ-102C

DECK A : 1 to 6 g • cm
(0.014 to 0.083 oz • inch)

DECK B : 2 to 9 g • cm

(0.028 to 0.125 oz • inch)

Reverse CQ-102RC

30 to 65 g • cm

(0.42 to 0.90 oz • inch)

Reverse
back
tension

CQ-102RC

1 to 6 g • cm

(0.014 to 0.083 oz • inch)

FF/REW

CQ-201B

70 to 120 g • cm

(0.97 to 1.67 oz • inch)

set

–

+

AF OSC

attenuator

10 kΩ

600 Ω

LINE IN

level mete

r

LINE OUT

47 kΩ

Standard Output Level

Test T ape

Input terminal LINE IN

source impedance 10 kΩ

input signal level 0.5 V (–3.8 dBs)

Tape Contents Use

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

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

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

Input terminal LINE IN

source impedance 10 kΩ

input signal level 0.5 V (–3.8 dBs)

9

TC-WE475

Record/Playback Head Azimuth Adjustment

DECK A DECK B

Procedure:

1. Forward Playback Mode

2. Turn the adjustment screw for the maximum output levels. If
these levels do not match, turn the adjustment screw until both
of output levels match together within 1 dB.

3. Playback Mode

4. Change the reverse playback mode and repeat the steps 1 to 3.

5. After the adjustment, lock the adjustment screws with suitable
locking compound.

Adjustment Location: – record/playback head –

Tape speed Adjustment DECK A DECK B

Adjust DECK A first
Procedure:

– Forward Playback Mode –

(High speed adjustment)

1. Press the PITCH CONTROL button to set to OFF .

2. Set to test mode. (Refer to page 11.)

3. Press the H button to playback.

4. Press the HIGH/NORMAL button to playback at double speed.

5. Adjust RV316 (DECK A), RV416 (DECK B) so that the fre­quency counter reading becomes 5,980 ± 180 Hz.

(Normal speed adjustment)

6. Press the H button to playback.

7. Press the HIGH/NORMAL button to playback at normal speed.

8. Adjust RV317 (DECK A), RV417 (DECK B) so that the fre­quency counter reading becomes 3,000 ± 90 Hz.

(Pitch control adjustment) (DECK A)

9. Press the PITCH CONTROL button to set to ON .

10. Set PITCH CONTROL knob to mechanical center.

11. Press the H button to playback.

12. Adjust RV318 so that the frequency counter reading becomes

2,990 ± 90 Hz.

Adjustment Location: MAIN board (See page 14.)

Sample value of wow and flutter

W.RMS (JIS) less than 0.3% .
(test tape : WS-48B)

Playback Level Adjustment DECK A DECK B

Procedure:

– Forward Playback Mode –

Adjust DECK A : RV111 (L-CH), RV211 (R-CH) and
DECK B : RV121 (L-CH), RV221 (R-CH) so the level meter read­ing becomes the adjustment limits below.

Adjustment V alue:

LINE OUT level : –7.7 dBs ± 0.5 dB (0.301 to 0.338 V)

Level difference between channels : within 0.5 dB

Confirm that the LINE OUT level does not change in playback mode
while changing the mode from playback to stop several times.

Adjustment Location: MAIN board (See page 14.)

set

test tape
P-4-A100
(10 kHz, –10 dB)

level mete

r

LINE OUT

47 kΩ

within
1 dB

within
1 dB

output
level

R-CH
peak

R-CH
peak

L-CH
peak

L-CH
peak

screw
position

screw position

VH

Screen Pattern

set

In phase 45˚ 90˚ 135˚ 180˚

good wrong

47 kΩ

47 kΩ

L-CH

R-CH

test tape
P-4-A100
(10 kHz, –10 dB)

LINE OUT

oscilloscope

forward sidereverse side

adjustment screws

set

frequency counter

47 kΩ

LINE OUT

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

set

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

level mete

r

LINE OUT

47 kΩ

10

TC-WE475

Bias Consumption Current Adjustment DECK B

This adjustment should be performed when replacing the head assy
or the bias oscillator transformer (T141, T241).

Setting:

REC LEVEL knob : standard recording position (See page 11.)

Procedure:

1. Connect the digital voltmeter to test point TP441.

2. Set RV141 (L-CH), RV241 (R-CH) to mechanical center.

3. Press the H button to playback.

4. Adjust T141 (L-CH), T241 (R-CH) so that the digital voltmeter
reading becomes minimum.

Adjustment V alue: Maximum 220 mV

Adjustment Location: MAIN board (See page 14.)

Record Bias Adjustment DECK B

Setting:

REC LEVEL knob : standard record position (See page 11.)

Procedure:

1. Set to test mode (See page 11.)

2. Insert a tape into deck B, press the REC z button and then
press the H button to start recording.

3. Record Mode

Record Level Adjustment DECK B

Setting:

REC LEVEL knob : standard record position (See page 11.)

Procedure:

1. Set to test mode (See page 11.)

2. Insert a tspe into deck B, press the REC z button and then
press the H button to start recording.

3. Record Mode

4. Playback Mode

set

321

blank tape
CS-413

TP441

L-CHR-CH

digital
voltmeter

LINE IN
no signal

set

AF OSC

attenuator

10 kΩ

600 Ω

LINE IN

1) 315 Hz

2) 10 kHz

50 mV (–23.8 dBs)

blank tap

e

CS-123

4. Playback Mode

set

recorded
portion

level mete

r

LINE OUT

47 kΩ

5. Confirm playback the signal recorded in step 2 become adjust­ment level as follows.
If the selevels do not adjustment lev el, adjust the R V141 (L-CH)
and RV241 (R-CH) to repeat steps 3 and 4.

Adjustment level:

The palyback output of 10 kHz level difference a gainst 315 Hz ref­erence should be ± 0.5 dB.

Adjustment Location: MAIN board (See page 14.)

set

AF OSC

attenuator

10 kΩ

600 Ω

LINE IN

blank tap

e

CS-123

315 Hz, 50 mV (–23.8 dBs)

set

recorded
portion

level mete

r

LINE OUT

47 kΩ

5. Confirm playback the signal recorded in step 2 become adjust­ment level as follows.
If the selevels do not adjustment lev el, adjust the R V101 (L-CH)
and RV201 (R-CH) to repeat steps 3 and 4.

Adjustment V alue:

LINE OUT level : –23.8 dBs ± 0.5 dB (47.2 to 53.0 mV)

Adjustment Location: MAIN board (See page 14.)

11

TC-WE475

Adjustment Location: main board

RV111

PB LEVEL

DECK A (L)

RV211

PB LEVEL

DECK A (R)

RV318

PITCH

CONTROL

(DECK A)

RV317

NORMAL SPEED

(DECK A)

RV316

HIGH SPEED

(DECK A)

100

81
80

51

31

1

IC801

50

30

RV417

NORMAL

SPEED

(DECK B)

RV416

HIGH

SPEED

(DECK B)

RV241

REC BIAS

DECK B (R)

RV141

REC BIAS

DECK B (L)

RV201

REC

LEVEL (R)

REC
BIAS

T241
BIAS

CURRENT

DECK B (R)

BIAS CURRENT

DECK B (L)

T141

52

33
32

20

64
1

IC551

19

51

RV101

REC

LEVEL (L)

RV121

PB LEVEL

DECK B (L)

RV221

PB LEVEL

DECK B (R)

TP441

[MAIN board] (Component side)

12

TC-WE475

SECTION 6

DIAGRAMS

6-1. CIRCUIT BOARDS LOCATION

TRANS (A) board (v E)

(Except SP)

MAIN board

RECVOL board (

v

G

)

H.P board (v D)

HEAD RELAY(REC/PB) board

(Deck B)

HEAD RELAY(PB) board

(Deck A)

LEAF SW (REC/PB) board

(Deck B)

PANEL board (

v

A)

DIRECTION board (

v

C)

POWER board (

v

F)

LEAF SW (REC/PB) board

(Deck A)

TRANS (B) board (v B)

• vA to vG are including into the mounted PANEL board.