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– 13 –

1. Clean the following parts with a denatured alcohol-moistened

swab:

record/playback heads

pinch rollers

erase head

rubber belts

capstan

idlers

2. Demagnetize the record/playback head with a head demagne-

tizer.

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

parts adjusted.

5. The adjustments should be performed with the rated power sup-

ply voltage unless otherwise noted.

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

71 to 143 g • cm

(0.98 – 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

Note: Perform this adjustments for both decks.

Procedure:
1. Mode : Playback

Signal

Used for

Tape

Mode

FWD

Torque meter

CQ-102C

Meter reading

FWD
back tension

REV

REV
back tension

FF/REW

FWD tension

REV tension

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

1. Demagnetize the record/playback head with a head damagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the

parts adjusted.

4. The adjustments should be performed with the rated power sup-

ply 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 adjust-
ment.)

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.

P-4-A100

WS-48B

P-4-L300

10 kHz, –10 dB

3 kHz, 0 dB

315 Hz, 0 dB

Azimuth Adjustment

Tape Speed Adjustment

Level Adjustment

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.

test tape
P-4-A100
(10kHz, –10dB)

MD OUT

level meter

set

+

–

L-CH
peak

R-CH
peak

screw
position

output
level

within
1 dB

L-CH
peak

R-CH
peak

screw
position

within 1dB

– 14 –

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

parts adjusted.

Adjustment Location: Playback Head (Deck A)

Record/Playback/Erase Head (Deck B)

3. Mode: Playback

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

speed adjustment.
In the test mode, the speed will switch to double speed or
normal speed each time the  HI DUB  button is pressed.

Procedure:
With the power turned ON, press the 

p  button,  ENTER/NEXT

button, and  DISC 3  button simultaneously.
(The “CD TYPE INDICATOR” on the fluorescent display tube will
blink while in the test mode.)
To exit the test mode, press the  

1/u  button.

1. Insert the WS-48B into deck B.
2. Press the  

(  button of deck B.

3. Press the  HI DUB  button and play the tape at double speed.
4. Adjust RV1001 of the LEAF SW board so that the reading of

the frequency counter becomes 6000 ± 180 Hz.

5. Press the  HI DUB  button and play the tape at normal speed.
6. Adjust RV1002 of the LEAF SW board so that the reading of

the frequency counter becomes 3000 ± 90 Hz.

Adjustment Location: LEAF SW 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:
CN301 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

test tape
P-4-A100
(10kHz, –10dB)

oscilloscope

set

Waveform of oscilloscope

in phase

45

°

90

°

135

°

180

°

good

wrong

MD OUT

Reverse

Foward

test tape 
P-4-L300
(315Hz, 0dB)

level meter

set

MD OUT

RV1002

RV1001

RV1002(Normal Speed)

RV1001(High Speed)

– 15 –

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:
CN403 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

AF OSC

VIDEO (AUDIO) IN
1) 315 Hz
2) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

} 50 mV (–23.8 dB)

AF OSC

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

blank tape
CS-123

set

attenuator

600 

Ω

recorded
position

level meter

set

MD OUT

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

– 16 –

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 (FEI) and GND, 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) 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 : 1.75 

±

 0.25 Vp-p

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

Adjustment Location: BD board