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25

Procedure:
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
automatically switch to MD.
(After recording, turn the  m/M  knob without stopping will
return to the position where recording was started.)

1.

Press the  FUNCTION  button to select MD. (This step is not
necessary if the above test mode has already been set.)

2.

Insert a tape into deck, press the  REC PAUSE/START  button,
and then press the  Y  button to start recording.

3.

Mode: Record

4.

Mode: Playback

5.

Confirm playback the signal recorded in step 2 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:
CN322 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)

AF OSC

MD (VIDEO) IN
315Hz 50 mV (–23.8 dB)

blank tape
CS-123

set

attenuator

600 

Ω

recorded
position

level meter

set

MAIN board
CN322
Pin 

5

 or TP42 (L-CH)

Pin 

9

 or TP46 (R-ch)

Note :

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

Therefore, check each item in order given.

2. Use YEDS-18 (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 if RF

signal level is correct or not.

Note:

Clear RF signal waveform means that the shape “ 

◊

 ” can be

clearly distinguished at the center of the waveform.

TP(RFAC)

BD board

oscilloscope

TP(DVC)

RF signal waveform

VOLT/DIV : 200mV
TIME/DIV : 500ns

level : 1.1 

±

0.4Vp-p

26

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 nine track.
4. Press the  BX  button. (Becomes the 1 track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscilloscope

waveform.

[BD BOARD] (Conductor Side)

TP(TE)
TP(DVC)

BD board

oscilloscope

level=1.0 

±

0.5Vp-p

symmetry

A (DC voltage)

center of
waveform

B

DVC

1 track jump waveform

VOLT/DIV: 500mV
TIME/DIV : 400

µ

s

IC103

TP (DVC)

TP (TE)

TP (RFAC)

IC102

TP308 (V-OUT)
TP307 (V-GND)

oscilloscope

(75 

Ω

 termination)

VIDEO board

0.714 

±

 0.05 Vp-p

Note:

1. Use the test disc HLV-402 (8-909-870-00) unless otherwise

indicated.

2. Use an oscilloscope with more than 10M

Ω impedance.

3. V-out terminal must be terminated by 75

Ω  at  video level

adjustment.

Procedure:
1.

Connect an oscilloscope to TP308 (V-OUT) and TP307 (V-
GND).

2.

Terminate TP308 (V-OUT) by 75

Ω.

3.

Turn the power on.

4.

Load the test disc (HLV-402).

5.

Playback the number ten track (100% white).

6.

Adjust the video level by turning the RV501 at the test point
TP308 (V-OUT)

Amplitude from blanking level to white level = 0.714 

± 0.05 Vp-p

waveform (NTSC, 100% white)

27

TP70 (54MHz)

frequency counter

VIDEO board

Procedure:
1.

Connect a frequency counter to the test point TP70 (54MHz,
DRCK).

2.

Press the  ?/1  button to turn the set on.

3.

Select the function “CD”.

4.

Confirm the frequency counter reading
54MHz 

± 1200Hz (reference value).

CN201

IC505

IC508

TP70

(54MHz)

TP307

(V-GND)

CN301

TP308

(V-OUT)

RV501

(VIDEO LEVEL)

28

AMP board

MAIN board 

TRANS board

TC board

PANEL board

MIC board

DISPLAY board

FRONT INPUT board

VOL board

THERMAL board

VOL SEL board

SUB POWER board 

MOTOR board

DRIVER board

TRAY SENSOR board

DISC SENSOR board

BD board

IN OUT SW board

VIDEO board

Note:
• All capacitors are in 

µ

F unless otherwise noted.  pF: 

µµ

F

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.

•

a

: Through hole.

•

: Pattern from the side which enables seeing.

•

A

: B+ Line.

•

B

: B– Line.

•

H

: adjustment for repair.

• Voltages and waveforms are dc with respect to ground

under no-signal (detuned) conditions.

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

Ω

).

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

•

∗

: Impossible to measure

• Waveforms are taken with a oscilloscope.

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

• Circled numbers refer to waveforms.

• Signal path.

F

: FM

E

: PB (TAPE)

a

: REC (TAPE)

J

: CD

g

: VIDEO

Note: The components identified by mark 

0

 or dotted line

with mark 

0

 are critical for safety.

Replace only with part number specified.

B

These are omitted.

C

E

B

These are omitted.

C

E

C

B

These are omitted.

E

Q

Caution:
Pattern face side:

Parts on the pattern face side seen from

(Conductor B)

the pattern face are indicated.

Parts face side:

Parts on the parts face side seen from

(Component A)

the parts face are indicated.