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17

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.
(After recording, press the  – 

0  button without stopping will

return to the position where recording was started.)

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

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

2. Insert a tape into deck B, press the  

r REC  button, and then

press the  

^  button to start recording.

3. Mode: Record

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.
(After recording, press the  – 

0  button without stopping will

return to the position where recording was started.)

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

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

2. Insert a tape into deck B, press the  

r REC  button, and then

press the  

^  button to start recording.

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:
J301 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)

Adjustment Location: MAIN board

[AUDIO BOARD] (Conductor Side)

4. Mode: Playback

[MAIN BOARD] (Conductor Side)

recorded
position

level meter

set

MD OUT
(J101)

AF OSC

VIDEO (AUDIO) IN (J101)
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

} 50 mV (–23.8 dB)

AF OSC

VIDEO (AUDIO) IN (J101)
315Hz 50 mV (–23.8 dB)

blank tape
CS-123

set

attenuator

600 

Ω

recorded
position

level meter

set

MD OUT
(J101)

RV441 RV341

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

RV301 RV401

RV341(Lch),RV441(Rch)
Record Bias

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

RV311

RV411

IC301

Record Level (L CH)
RV301

CN303

RV351
Record Level (R CH)

56

43 42

29

28

15

14

1

18

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.

Adjustment Location: BD board

Procedure :
1. Connect the oscilloscope to test points TP (FE) and TP (VC).
2. Connect TP (FE1) and TP (VC), and TP (AGCCON) and GND

of the BD board with lead wires.

3. Press the  

1/u  button to turn the set ON.

4. With the disc (YEDS-18) loaded, press the  

^  button and

perform focus search. (Focus search will be performed in the
same way even while the disc table is pushed in and out.)

5. Check the symmetry and peak to peak level of the oscilloscope

waveform (S curve) at this time.

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.

Adjustment Location: BD board

Procedure :
1. Connect oscilloscope to test point TP (RF) and TP (VC) on BD

board.

2. Connect TP (AGCCON) and GND of the BD board with lead

wires.

3. Press the  

1/u  button to turn the set ON.

4. Put disc (YEDS-18) in and playback 5track.
5. Confirm that oscilloscope waveform is clear and check RF sig-

nal level is correct or not.

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

oscilloscope

BD board

TP (FE)
TP (VC)

+
–

oscilloscope

BD board

TP (RF)
TP (VC)

+
–

oscilloscope

BD board

TP (TE)
TP (VC)

+
–

Adjustment Location: BD board

Procedure :
1. Connect oscilloscpe to test point TP (TE) and TP (VC) on BD

board.

2. Short-circuit SL502 of the video board to GND.
3. Turned Power switch on. Press  FUNCTION  button to select

CD.

4. Put disc (YEDS-18) in to play the number five track.
5. Press the  PLAY MODE/DOLBY NR  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

0V

level : 1.3 

±

 0.6 Vp-p

A (DC voltage)

Center of the waveform

B

7. Press the  PLAY MODE/DOLBY NR  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

symmetry

A

B

Within 4.0 

±

 1.0 Vp-p

Clear RF signal waveform means that the shape “

◊

” can be

clearly distinguished at the center of the waveform.

RF signal waveform

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

level : 1.45 

±

 0.3 Vp-p

8. Desolder the short-land (SL502) short-circuited at step 2.

Adjustment Location: BD board

19

1. Connect the frequency counter to check point (27MHz) of the

VIDEO board.

2. Adjust CT503 of the VIDEO board so that the frequency counter

read 27MHz ± 80Hz at STOP condition.

frequency counter

VIDEO board
(27 MHz)

+
–

TP (VC)

TP (RF)

TP (TE)

TP (FE)

IC102

IC103

IC101

TP (FE)

TP
(AGCCON)

CN501

1

30

80

SL501

SL502

SL503

CN502

51

IC505

31

(GND)

CT503

VIDEO

Frequency

Adjustment

Check point

(27 MHz)

50

100

81

D502

20

MAIN board

PANEL board

CD SW board

TUNER unit

TRANS board

VIDEO board

5V power board

SENSOR board

CONNECTOR board

BD board

MOTOR (SLIDE) board

MOTOR (TURN) board

3CH AMP board

FRONT AMP board

AUDIO board

LEAF SW board

TUNER unit is supplied as
the assembled block.