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Procedure:
1.

Mode : Playback

2.

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

P-4-A100

WS-48B

10 kHz, –10 dB

3 kHz, 0 dB

Azimuth Adjustment

Tape Speed Adjustment

1.

Demagnetize the record/playback head with a head demagnetizer.

2.

Do not use a magnetized screwdriver for the adjustments.

3.

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

4.

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

5.

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

6.

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

7.

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

4.

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

Adjustment Location: Record/Playback/Erase Head

Procedure:
1.

Turn the power on.

2.

Insert the WS-48B into deck.

3.

Press the N button of deck.

4.

Check the reading of frequency counter becomes 3000 ± 90 Hz.

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

3.

Mode: Playback

°

°

°

°

Adjustment Location: Record/Playback Head.

Checking Location: CD board (Conductor side)

Procedure:
1.

Connect an oscilloscope to test point TP (RFAC) and TP (VC)
on the CD board.

2.

Turn the power on.

3.

Put the disc (YEDS-18) in to playback the number five track.

4.

Confirm that oscilloscope waveform is clear and check RFAC
signal level is correct or not.

A clear RFAC signal waveform means that the shape “

◊” can be

clearly distinguished at the center of the waveform.

Checking Location: CD board (Conductor side)

1. CD Block is basically designed to operate without adjustment. There-

fore, check each item in order given.

2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M

Ω impedance.

4. Clean the object lens by an applicator with neutral detergent when the

signal level is low than specified value with the following checks.

Procedure:
1.

Connect an oscilloscope to test point TP (FE) and TP (DVC)
on the CD board.

2.

Turn the power on.

3.

Put the disc (YEDS-18) in and turned power switch on again
and actuate the focus search. (actuate the focus search when
disc table is moving in and out)

4.

Check the oscilloscope waveform (S-curve) is symmetrical
between A and B. And confirm peak to peak level within 2 ± 1
Vp-p.

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

or B : A is more than 10 : 7.

• Take sweep time as long as possible and light up the

brightness to obtain best waveform.

Checking Location: CD board (Conductor side)

Procedure:
1.

Connect an oscilloscope to test point TP (RFDC) and TP (DVC)
on the CD board.

2.

Turn the power on.

3.

Put the disc (YEDS-18) in to playback the number five track.

4.

Confirm that oscilloscope waveform is clear and check RFDC
signal level is correct or not.

A clear RFDC signal waveform means that the shape “

◊” can be

clearly distinguished at the center of the waveform.

±

±

±

15

15

Procedure:
1.

Connect an oscilloscpe to test point TP (TE) and TP (DVC) on
the CD board.

2.

AC is put in pushing  CD 

N

button.

3.

FL tube carries out all lights and goes into CD test mode.

4.

Put the disc (YEDS-18) in to playback the number five track.

5.

Press the  CD 

N

button.  (The tracking servo and the sledding

servo are turned OFF)

6.

Check the level B of the oscilliscope's waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 22%

Traverse Waveform

7.

Press the  CD 

N

button. (The tracking servo and sledding

servo are turned ON)
Confirm the C (DC voltage) is almost equal to the A (DC
voltage) is step 4.

8.

To exit from this mode, turn the power off.

• Always move the optical pick-up to most inside track when

exiting from this mode. Otherwise, a disc will not be unloaded.

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

be chipped.

Traverse Waveform

Checking Location: CD board (Conductor side)

+
–

CD board

TP (TE)

TP (DVC)

oscilloscope

0V

B

level: 1.15 

±

 0.5 Vp-p

Center of 
the waveform

A (DC 

voltage)

0V

Tracking servo

Sled servo

ON

C (DC 
voltage)

Tracking servo

Sled servo

OFF

TP (VC)

TP (FE)

TP (TE)

TP

 (RFDC)

TP

 (DVC)

TP

 (RFAC)

IC103

IC101

16

16

Note:
• All capacitors are in µF unless otherwise noted.  pF: µµF

50 WV or less are not indicated except for electrolytics
and tantalums.

• All resistors are in 

Ω

 and 

1

/

4

 

W or less unless otherwise

specified.

•

f

: internal component.

•

2

: nonflammable resistor.

•

1

: fusible resistor.

•

C

: panel designation.

• X

: parts extracted from the component side.

• Y

: parts extracted from the conductor side.

•

f

: internal component.

•

: Pattern from the side which enables seeing.

•

A

: B+ Line.

•

B

: B– Line.

• Voltages are taken with a VOM (Input impedance 10 M

Ω

).

Voltage variations may be noted due to normal produc-
tion tolerances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal produc-
tion tolerances.

• Circled numbers refer to waveforms.
• Abbreviation

CND : Canadian model

• Signal path.

F

: TUNER (FM)

J

: CD

d

: MD

E

: PB (TAPE)

a

: REC (TAPE)

Note:
The components identified by
mark 

0

 or dotted line with mark

0

 are critical for safety.

Replace only with part number
specified.

Note:
Les composants identifiés par
une marque 

0

  sont critiques

pour la sécurité.
Ne les remplacer que par une
pièce portant le numéro spécifié.

C

B

E

Q

B

C

E

MAIN board

CONTROL board

BACK LIGHT board

TRANSFORMER board  

CD board