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33

4.

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

Procedure:
1.

MODE : FWD Playback.

2.

Insert the WS-48B into deck.

3.

Press the  TAPE Y  button of deck.

4.

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

W.RMS (JIS) less than 0.35%
(test tape: WS-48B)

3.

Mode: Playback

test tape
P-4-A100
(10kHz, –10dB)

oscilloscope

set

Waveform of oscilloscope

in phase

45

°

90

°

135

°

180

°

good

wrong

R-ch

L-ch

V

H

Pin     (GND)

MAIN board
CN105
Pin     (L-CH) 

4

6

2

Pin     (R-CH)

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

frequency
counter

set

Pin     (GND)

4

6

2

MAIN board 
CN105
Pin     (L-CH) or
Pin     (R-CH)

 DSG OFF, TREBLE/BASS CENTER

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.

L-CH
peak

R-CH
peak

screw
position

output
level

within
1 dB

L-CH
peak

R-CH
peak

screw
position

within 1dB

1.

Demagnetize the record/playback head with a head demagne-
tizer.

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 ad-
justment.)

6.

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

7.

Switches and controls should be set as follows unless other-
wise specified.

test tape
P-4-A100
(10kHz, –10dB)

level meter

set

+

–

Pin     (GND)

MAIN board 
CN105
Pin     (L-CH) or
Pin     (R-CH)

4

6

2

Tape

P-4-A100

WS-48B

10 kHz, –10 dB

3 kHz, 0 dB

Azimuth Adjustment

Tape Speed Adjustment

Signal

Used for

34

Procedure :
1. Press the  FUNCTION  button to select ANALOG IN.
2. Insert a tape into deck, press the  z TAPE  button, and then

press the  X TAPE  button to start recording.

3. Mode : Record

4. Mode : Playback

5. Confirm playback the signal recorded in step  become adjustment

level as follows
If these levels do not satisfy adjustment level, adjust the RV653
(L-CH) and RV603 (R-CH) on the TC board to repeat steps 3
and 4.

Adjustment level : The playback output of 10kHz level difference

against 315Hz reference should be 0 

± 2.0dB.

Adjustment Location :

AF OSC

ANALOG IN  (SJ302) 
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

34.6 mV (–27 dB)

recorded
position

level meter

set

Pin     (GND)

MAIN board 
CN105
Pin     (L-CH) or
Pin     (R-CH)

4

6

2

CN105

19
18

1
2

Procedure :
1. Press the  FUNCTION  button to select ANALOG IN.
2. Insert a tape into deck, press the  z TAPE  button, and then

press the  X TAPE  button to start recording.

3. Mode : Record

4. Mode : Playback

5. Confirm playback the signal recorded in step  become adjustment

level as follows
If these levels do not satisfy adjustment level, adjust the RV652
(L-CH) and RV602 (R-CH) on the TC board to repeat steps 3
and 4.

Adjustment level :
playback Level : 30.8 to 38.8mV (–28 to –26dB).

Adjustment Location :

AF OSC

ANALOG IN  (SJ302) 
315 Hz

blank tape
CS-123

set

attenuator

600 

Ω

34.6 mV (–27 dB)

recorded
position

level meter

set

Pin     (GND)

MAIN board 
CN105
Pin     (L-CH) or
Pin     (R-CH)

4

6

2

RV652

(L-CH)

RV602

(R-CH)

RV653

(L-CH)

RV603

(R-CH)

Record Level

Record Bias

35

Procedure:
1.

Connect an oscilloscope to TP (TE) and TP (DVC).

2.

Turn the power on.

3.

Load a disc (YEDS-18) and playback the number five track.

4.

Press the  CD u  button. (Becomes the 1track jump mode.)

5.

Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.

Specification level:      

x

 100=less than ±22%

0V

Center of
waveform

B

Symmetry

A (DC voltage)

level=1.1 

±

0.6Vp-p

A

B

Note :

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

Therefore, 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 TP (RFAC) and TP (DVC).
2. Turn the power on.
3. Load a disc (YEDS-18) and playback the number five track.
4. Confirm that oscilloscope waveform is clear and check RF signal

level is correct or not.

Clear RF signal waveform means that the shape “

◊” can be

clearly distinguished at the center of the waveform.

TP(RFAC)
TP(DVC)

BD (CD) BOARD

oscilloscope

VOLT/DIV : 200mV
TIME/DIV : 500ns

level : 1.1 

±

 0.3Vp-p 

BD (CD) BOARD

Oscilloscope

TP (TE)
TP (DVC)

IC101

IC103

IC104

TP (DVC)

TP (TE)

TP (RFAC)

36

Other faults are suspected.
Check the mechanism parts (spindle motor, sled motor, etc.).

Start

NG

NG

NG

OK

OK

OK

Laser Power Check

6-2.

(See page 39)

6-3.

(See page 39)

6-4.

(See page 40)

Iop Compare

Auto Check

Replace optical pick-up or MDM-7S2D

About “R”
As this unit has only a few buttons, some operations require the use of remote commander (RM-SM100EW/provided with unit) buttons.
These operations are indicated as “R” in this manual.
Example: MENU/NO “R” ...Press the  MENU/NO  button of the remote commander.

Incorrect operations may be performed if the MD test mode is not entered properly.
In this case, press the ?/1 button to turn the power off, and retry to enter the MD test mode.

If malfunctions caused by optical pick-up such as sound skipping are suspected, follow the following check.