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33

3.04 – 6.96 N • m

(31 to 71 g • cm)

(0.43 – 0.98 oz • inch)

0.20 – 0.58 N • m

(2 to 6 g • cm)

(0.02 – 0.08 oz • inch)

3.04 – 6.96 N • m

(31 to 71 g • cm)

(0.43 – 0.98 oz • inch)

0.20 – 0.58 N • m

(2 to 6 g • cm)

(0.02 – 0.08 oz • inch)

6.97 – 14.02 N • m

(71 to 143 g • cm)

(0.98 – 1.99 oz • inch)

0.98 N • m or more

(100 g or more)

(3.53 oz or more)

0.98 N • m or more

(100 g or more)

(3.53 oz or more)

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

Precaution
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.

Note: Perform this adjustments for both decks.

Procedure:
1. Mode : Playback

Signal

Used for

Tape

Mode

FWD

FWD
back tension

REV

REV
back tension

FF/REW

FWD tension

REV tension

Torque meter

Meter reading

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 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.

main board
CN302
Pin 1 (L-ch)
Pin 3 (R-ch)

34

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  HIGH-SPEED CD-MD SYNC  but-
ton is pressed.

Procedure:
With the power turned ON, press the  x  button,  DISPLAY  button,
and  DISC 3  button simultaneously.
(The “VOLUME” on the fluorescent display tube will blink while
in the test mode.)
To exit the test mode, press the  "/1  button.

1. Insert the WS-48B into deck B.
2. Press the  H  button of deck B.
3. Press the  HIGH-SPEED CD-MD SYNC  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  HIGH-SPEED CD-MD SYNC  button and play the tape at

°

°

°

°

Pin 2 (GND)

main board
CN302
Pin 1 (L-ch)

Pin 3 (R-ch)

main board
CN302
Pin 1 (L-ch)
Pin 3 (R-ch)

normal speed.

6. Adjust RV1002 of the LEAF SW board so that the reading of

the frequency counter becomes 3000 ± 90 Hz.

7. Press the  "/1  button, after the turned ON.
8. Insert the WS-48B into deck A, and insert the normal tape into

deck B.

9. Press the  SYNC REC  button and display "TAPE  A t B HIGH-

SPEED" and then press the REC button to start recording.

10.Press the x  button.
11.Press the H button of deck B and check the reading of fre-

quency 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:
CN302 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

35

INTRODUCTION
When set to the test mode performed in Tape Speed Adjust-
ment, 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  m  button without stopping will re-
turn 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  TAPE REC PAUSE/START

button, and then press the  H  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 0 ± 0.5 dB.

Adjustment Location: AUDIO board

INTRODUCTION
When set to the test mode performed in Tape Speed Adjust-
ment, 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.
(After recording, press the  m  button without stopping will re-
turn 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  TAPE REC PAUSE/START

button, and then press the  H  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:
CN302 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)

Adjustment Location: MAIN board

4. Mode: Playback

main board
CN302
Pin 1 (L-ch)
Pin 3 (R-ch)

Ω

Ω

main board
CN302
Pin 1 (L-ch)
Pin 3 (R-ch)

36

Note :
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 fol-
lowing checks.

Procedure :
1. Connect oscilloscope to TP (FEO).
2. Connect between TP (FEI) and TP (VC) by lead wire.
3. Connect between TP (AGCCON) and TP (GND) by lead wire.
4. Turn  ?/1  button on.
5. Load a disc (YEDS-18) and actuate the focus search. (In conse-

quence of open and close the disc tray, actuate the focus search)

6. Confirm that the oscilloscope waveform (S-curve) is symmetri-

cal between A and B. And confirm peak to peak level within 4
±1 Vp-p.

7. After check, remove the lead wire connected in step 2 and 3.
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

brightness to obtain best waveform.

Procedure :
1. Connect oscilloscope to TP (RF).
2. Connect between TP (AGCCON) and TP (GND) by lead wire.
3. Turned  ?/1  button on.
4. Load a disc (YEDS-18) and playback.
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.

±

Note : Clear RF signal waveform means that the shape “ 

◊

 ” can be

clearly distinguished at the center of the waveform.

Procedure :
1. Connect oscilloscope to TP (TEO) and TP (VC).
2. Turned  ?/1  button on.
3. Load a disc (YEDS-18) and playback the number five track.
4. Press the  u  button. (Becomes the 1 track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscillo-

scope waveform.

6. After check, remove the lead wire connected in step 1.

[BD (CD) BOARD] (Conductor Side)

±

±

Specified level:      

×

 100 = less than 

±

 22 %

B

A