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– 13 –

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

parts adjusted.

Adjustment Location: Playback Head (Deck A)

Record/Playback/Erase Head (Deck B)

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.

3. Mode: Playback

Note: Set the test mode using the following method and begin tape

speed adjustment.
In the test mode, the tape will move at double speed or normal
speed each time the  H SPEED DUB.  button is pressed.

Procedure :
With the power turned ON, press the  SPECTRUM ANALYZER
button,  ENTER  button, and  EFFECT  button simultaneously.
(The “VOLUME” on the fluorescent display tube will blink while
in the test mode.)
To exit the test mode, press the  1/u  button.

1. Load WS-48B into deck B.
2. Play deck B.
3. Press the  H SPEED DUB.  button and play the tape at double

speed.

4. Adjust RV652 of the AUDIO board so that the reading of the

frequency counter becomes 6000 ± 180 Hz.

5. Press the  H SPEED DUB.  button and play the tape at normal

speed.

6. Adjust RV651 of the AUDIO board so that the reading of the

frequency counter becomes 3000 ± 90 Hz.

Adjustment Location: AUDIO board

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

Procedure:
Mode: Playback

Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301
(L-CH) and RV401 (R-CH)
so that adjustment within the following adjustment level.

Adjustment level:
CN403 playback level: 301.5 to 338.3 mV (–8.2 to –7.2 dB)
level difference between the channels: within ± 0.5 dB
Adjustment Location: AUDIO board

L-CH
peak

R-CH
peak

screw
position

output
level

within
1 dB

L-CH
peak

R-CH
peak

screw
position

within 1dB

test tape
P-4-A100
(10kHz, –10dB)

oscilloscope

set

L

R

Waveform of oscilloscope

in phase

45

°

90

°

135

°

180

°

good

wrong

main board
CN403
Pin 

3

 (L-CH)

Pin 

2

 (GND)

Pin 

1

 (R-CH)

reverse

forward

test tape 
P-4-L300
(315Hz, 0dB)

level meter

set

main board
CN403

Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

– 14 –

INTRODUCTION
When set to the test mode performed in 

,

when the tape is rewound after recording, the “REC memory

mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will auto-
matically switch to VIDEO.

1. Press  FUNCTION  button to select VIDEO. (This step is not

necessary if the above test mode has already been set.)

2. Load a tape into deck B, and press the  r REC  button.
3. Mode: Record

4. Mode: Playback

5. Confirm playback the signal recorded in step 2 become adjust-

ment level as follows.
If these levels do not adjustment level, adjust the RV341 (L-CH)
and RV441 (R-CH) on the AUDIO board to repeat steps 3 and 4.

Adjustment level: The playback output of 10 kHz level difference

against 315 Hz reference should be ± 1.0 dB.

Adjustment Location: AUDIO board

INTRODUCTION
When set to the test mode performed in 

, when the tape is rewound after recording, the “REC memory

mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this
adjustment. During recording, the input signal FUNCTION will au-
tomatically switch to VIDEO.

1. Press  FUNCTION  button to select VIDEO. (This step is not

necessary if the above test mode has already been set.)

2. Load a tape into deck B, and press the  r REC  button.
3. Mode: Record

4. Mode: Playback

5. Confirm playback the signal recorded in step 2 become adjust-

ment level as follows.
If these levels do not adjustment level, adjust the RV301 (L-CH)
and RV351 (R-CH) on the MAIN board to repeat steps 3 and 4.

Adjustment level:
CN403 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)

Adjustment Location: MAIN board

Adjustment Location
[AUDIO BOARD] (Conductor Side)

[MAIN BOARD] (Component Side)

AF OSC

VIDEO/MD (AUDIO) IN
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

} 50 mV (–23.8 dB)

recorded
position

level meter

set

main board
CN403

Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

AF OSC

VIDEO/MD (AUDIO) IN
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

} 50 mV (–23.8 dB)

recorded
position

level meter

set

main board
CN403

Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

RV341(Lch),RV441(Rch)
Record Bias

RV301

RV401

RV441 RV341

RV301(Lch),RV401(Rch)
Playback Level (Deck B)

RV651 (Normal Speed)
RV652 (High Speed)
Tape Speed

RV651

RV311(Lch),RV411(Rch)
Playback Level (Deck A)

RV652

RV311

RV411

CN403

IC401

1

3

RV351
Record Level
(R CH)

RV301
Record Level (L CH)

– 15 –

1. CD Block is basically constructed 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 oscilloscope to test point TP (FEO).
2. Connect between test point TP (FOK) and Ground by lead wire.
3. Turn Power switch on.
4. Put 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.)

5. Check the oscilloscope waveform (S-curve) is symmetrical be-

tween A and B. And confirm peak to peak level within 3 ± 1Vp-p.

S-curve waveform

6. After check, remove the lead wire connected in step 2.

 • 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 bright-

ness to obtain best waveform.

Procedure :
1. Connect oscilloscope to test point TP (RF) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Confirm that oscilloscope waveform is clear and check RF sig-

nal level is correct or not.

Clear RF signal waveform means that the shape “

◊

” can be

clearly distinguished at the center of the waveform.

RF signal waveform

Procedure:
1. Connect oscilloscope to test point TP (TEO) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in to play the number five track.
4. Press the “P (Pause)” button.
5. Check the level B of the oscilloscope's waveform and the A (DC

voltage) of the center of the Traverse waveform.
Confirm the following:

• A/B x 100 = less then ± 7 (%)
• B = 500 ± 100 mVp-p

1 track jump waveform

[BD BOARD]  (Conductor Side)

symmetry

A

B

Within 3 

±

 1 Vp-p

oscilloscope

BD board

TP (FEO)
TP (VC)

oscilloscope

BD board

TP (RF)
TP (VC)

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

level : 1.3 

±

 0.3 Vp-p

oscilloscope

BD board

TP (TEO)
TP (VC)

0V

Center of the waveform

B

Symmetry

A (DC voitage)

level : 500 mV 

±

 100 mVp-p

TP (RF)

TP
(FOK)

IC101

TP

(VC)

TP
(GND)

TP

(TEO)

TP
(FEO)

IC103

IC102

IC102

CN101

– 16 –

pA is including in AUDIO board.

p

A

MOTOR board

LEAF SWITCH board

BD board

LED board

CD MOTOR board

TABLE SENSOR board

AUDIO board

(including 

p

A) 

TRANS board

ENCAPSULATED COMPONENT

SURROUND board

MAIN board

KYECON board

POWER board

CD-B1 SW board

CD-B2 SW board

TC-B SW board

TC-A SW board

HP/MIC board

PANEL board

DOOR SW board

CD-A SW board

CD-LED board