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17

0 dB=0.775 V

1. Demagnetize the record/playback head with a head

demagnetizer.

2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the

parts adjust.

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
adjustment.)

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

CH.

7. Switches and controls should be set as follows unless otherwise

specified.

• Test Tape

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0 dB

Tape Speed Adjustment

P-4-L300

315 Hz, 0 dB

Level Adjustment

Note:  Perform this adjustments for both decks

Procedure:
1. Mode:  Playback

main board
CN301
Pin 3 (L-CH)
Pin 1 (R-CH)

main board
CN301
Pin 2 (GND)

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 1dB of peak.

3. Mode:  Playback

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

pats adjusted.

Adjustment Location: Playback Head (Deck A).

Record/Playback/Erase Head (Deck B).

pin 1

° 90° 135° 180°

pin 2

pin 3

forward

reverse

18

Procedure:
INTRODUCTION
When set to the test mode performed in Tape Speed Adjustment,
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 VIDEO.
(If do not operation of stopped from recording complete, and rotette
of shuttle knob then rewind to recording start position.)

1. Press  MD (VIDEO)  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.
3. After press  REC PAUSE/START  button, press REC PAUSE/

START button, then recording start.

4. Mode:  Record

5. Mode:  Playback

6. Confirm playback the signal recorded in step 3 become

adjustable level as follows.
If these levels do not adjustable level, adjustment the RV304
(L-CH) and RV354 (R-CH) on the AUDIO board to repeat steps
4 and 5.

Adjustable level: Playback output of 315 Hz to playback output

of 10 kHz:  0

±0.5 dB

Adjustment Location:  MAIN board

Procedure:
INTRODUCTION
When set to the test mode performed in Tape Speed Adjustment,
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 VIDEO.
(If do not operation of stopped from recording complete, and rotate
of shuttle knob then rewind to recording start position.)

1. Press  MD (VIDEO)   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.
3. After press  REC PAUSE/START  button, press REC PAUSE/

START button, then recording start.







Ω

CN301 (Pin 3 : L-CH)

(Pin 1 : R-CH)

Note: Start the Tape Speed adjustment as below after setting to the test

mode.
In the test mode, the tape speed is high during pressing

 CD SYNC HI-DUB 

 button.

Procedure:
1. Turn the power switch on.
2. Press  x button,  DISPLAY  button and  DISC 3  button

simultaneously.
(Cursor segment flash on the FL display tube.)
To exit from the test mode, press ?/1 button.

Mode:  Playback

1. Insert the WS-48B into the deck B.
2. Press Y button on the deck B.
3. Press  CD SYNC HI-DUB  button in playback mode.

Then at HIGH speed mode.

4. Adjust RV1001 on the LEAF SW board do that frequency

counter reads 6,000 

± 180 Hz.

5. Press  CD SYNC HI-DUB  button.

Then back to NORMAL speed mode.

6. Adjust RV1002 on the LEAF SW board so that frequency

counter reads 3,000 

± 90 Hz.

Adjustment Location:  LEAF SW board

Procedure:
Mode:  Playback

Deck A is RV302 (L-CH), Deck B is RV303 (L-CH) so that
adjustment within adjustment level as follows.
Adjustment Level:

CN301 PB level:  334 to 375 mV (–6.8 dB 

± 0.5 dB) level

difference between the channels:  within 

±0.5 dB

Adjustment Location:  MAIN board

Sample Volue of Wow and Flutter: 0.3% or less W. RMS

  (WS-48B)

main board
CN301 (Pin 3 : L-CH)

(Pin 1 : R-CH)

main board
CN301 (Pin 3 : L-CH)

(Pin 1 : R-CH)

19

4. Mode:  Record

5. Mode:  Playback

6. Confirm playback the signal recorded in step 3 become

adjustable level as follows.
If these levels do not adjustable level, adjustment the RV301
(L-CH) and RV351 (R-CH) on the MAIN board to repeat steps
4 and 5.

Adjustable level:
CN301 PB level:  33.4 to 37.5 mV (–27.3 to –26.3 dB)
Adjustment Location:  MAIN board

[MAIN  BOARD] (Component Side)

[LEAF  SW  BOARD]  (Component Side)

Ω

CN301 (Pin 3 : L-CH)

(Pin 1 : R-CH)





















CN301

RV354

RV304

RV351

CN304

T11

RV11

RV302

RV301

RV303

REC LEVEL (L)

(B)

PB LEVEL (L)

(A)

PB LEVEL (L)

(B)

REC LEVEL (R)

(B)

REC BIAS (R)

(B)

REC BIAS (L)

(B)

Procedure:
1.

Supply a 25 dB 98 MHz signal from the ANTENNA terminal.

2.

Tune the set to 98 MHz.

3.

Adjust RV11 to the point (moment) when the TUNED indicator
will change from going off to going on.

Adjustment Location: MAIN board

Procedure:
1.

Supply a 60 dB

 

98 MHz signal from the ANTENNA terminal.

2.

Tune the set to 98 MHz.

3.

Measure voltage between pin 22 and pin 3 of IC 11.  Adjust
T11 ubtil the voltage becomes 0 V.

Adjustment Location: MAIN board

FM RF SSG

75 

Ω

 coaxial

Carrier frequency : 98 MHz
Modulation           : AUDIO 1 kHz, 75 kHz
                              deviation (100%)
Output level          : 25 dB  (at 75 

Ω

 open)

FM ANTENNA terminal
(TM1)

set

Ω coaxial

Ω open)

CN301

RV354

RV304

RV351

CN304

T11

RV11

IC11

12

1

13

24

RV302

RV301

RV303

NULL

FM TUNED LEVEL

20

Note :

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

Therefore, check each item in order given.

2. Use HLX-504 (J-6090-088-A) or HLX-505 (J-6090-089-A)

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.

Video Level Adjustment (MB BOARD)
Purpose
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.

Procedure:
1. Connect oscilloscope to VIDEO output.
2. Load a disc (HLX-504 or HL-505) playback.
3. Adjust the RV501 to attain 1.0

±0.1Vp-p.

J601
VIDEO OUTPUT

75 

Ω

Oscilloscope

set

1.0 

± 0.1 Vp-p

(WHITE 75%)

S-terminal Output Check
Purpose
Check S-video output.

J602
S-VIDEO OUTPUT

75 

Ω

Oscilloscope

G

G

set

Procedure:
1. Connect oscilloscope to S-VIDEO out. (S-Y teminal)
2. Load a disc (HLX-504 or HL-505) playback.

3. Confirm that the S-Y level is 1.0 

± 0.1Vp-p.

1.0 

± 0.1 Vp-p

4. Connect oscilloscope to S-VIDEO output. (S-C teminal)
5. Connect that the S-C burst is 286 

± 50mVp-p.

286 

± 80 mVp-p

CN011

IC503

IC103

CN103

CN008

CN404

RV501

VIDEO LEVEL

Adjustment