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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)

test tape 
P-4-L300
(315Hz, 0dB)

level meter

set

main board
CN403

Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

reverse

forward

– 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)

recorded
position

level meter

set

main board
CN403

Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

recorded
position

level meter

set

main board
CN403

Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

[MAIN BOARD] (Component Side)

CN403

IC401

1

3

RV351
Record Level
(R CH)

RV301
Record Level (L 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

AF OSC

VIDEO (AUDIO)
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

} 50 mV (–23.8 dB)

AF OSC

VIDEO (AUDIO)
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

} 50 mV (–23.8 dB)

– 15 –

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.

Note : A 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 (FE) on BD board.
2. Connect between test point TP (FEI) and TP (VC) by lead wire.
3. Turned 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±1 Vp-p.

S-curve waveform

oscilloscope

BD board

TP (FE)
TP (VC)

+
–

symmetry

A

B

Within 3 

±

 1 Vp-p

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

oscilloscope

BD board

TP (RF)
TP (VC)

+
–

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

nal level is correct or not.

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

level : 1.3           Vp-p

+0.25
–0.20

oscilloscope

BD board

TP (TE)
TP (VC)

+
–

Procedure :
1. Connect oscilloscpe to test point TP (TE) on BD board.
2. Connect the lead wire to both ends of the land of SL702 (ADJ)

and SL703 (AFADJ) of the VIDEO board.

3. Turned Power switch on. Press  FUNCTION  button to select

CD.

4. Short the lead wire.
5. Put disc (YEDS-18) in to play the number five track.
6. Press the  REPEAT  button. (The tracking servo and the sled-

ding servo are turned OFF.)

7. 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

0V

level : 1.3 

±

 0.6 Vp-p

A (DC voltage)

Center of the waveform

B

8. Press the  REPEAT  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 7.

Traverse waveform

0V

C (DC 
voltage)

Tracking servo
Sled servo
        OFF

Tracking servo
Sled servo
        ON

9. Remove the lead wire connected step 1.

– 16 –

1. Connect the frequency counter to check point of the VIDEO

board.

frequency counter

VIDEO board
TP410 (DCLK)

+
–

2. Adjust CT401 of the VIDEO board so that the frequency counter

read 13.5MHz ± 40Hz at STOP condition.

[ BD BOARD ] — SIDE A —

[ VIDEO BOARD ] — SIDE B —

1

20

10

11

IC103

(RF)

(FE)

(FEI)

(TE)

(VC)

IC101

SL703 (AFADJ)

IC751

IC251

SL702 (ADJ)

SL701 (CAL BAR)

CT401

Video

Frequency

TP410 (DCLK)