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IC502 of the VIDEO board consists of the former type and new type. The following table shows the differences between the two types.
Only spare parts for the new type IC502 are supplied.
Units using the former IC502 will not function when replaced with the new type without performing the following procedure.
Consequently, replace IC502 of units using the former type according to the following procedure.

FORMER TYPE

NEW TYPE

C407, 408

MOUNT

NO MOUNT

IC502

M306200MC-302FP

M306200MC-305FP

JW421, JW422

NO MOUNT

MOUNT

IC402

MOUNT

NO MOUNT

R413, 421, 422

MOUNT

NO MOUNT

X401

MOUNT

NO MOUNT

1. Remove IC402.
2. Solder JW421 and JW422, or short-circuit with a lead wire, etc.
3. Replace IC502 with a new one.

Those with IC402: FORMER TYPE
Those without:

NEW TYPE

IC505

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• The cold reset clears all data including preset data stored in the RAM to initial conditions. Execute this mode when returning the set to the

customer.

Procedure:
1. Press three buttons  p  ,  ENTER/NEXT  , and  1/u  simultaneously.
2. The fluorescent indicator tube becomes blank instantaneously, and the set is reset.

• This mode moves the pick-up to the position durable to vibration. Use this mode when returning the set to the customer after repair.
Procedure:
1. Press  1/u  button to turn the set ON.
2. Press  CD LOOP  button and  1/u  button simultaneously.
3. A message “LOCK” is displayed on the fluorescent indicator tube, and the CD delivery mode is set.

• This mode resets the set with the preset data kept stored in the memory.  The hot reset mode functions same as if the power cord is plugged

in and out.

Procedure:
1. Press three buttons  p  ,  ENTER/NEXT  , and  DISC 1  simultaneously.
2. The fluorescent indicator tube becomes blank instantaneously, and the set is reset.

• This mode can run the CD sled motor freely. Use this mode, for instance, when cleaning the pick-up.
Procedure:
1. Select the function “CD”.
2. Press three buttons  p  ,  ENTER/NEXT  , and  §  simultaneously.
3. The Sled Servo mode is selected, if “CD” is blanking on the fluorescent indicator tube.
4. With the CD in stop status, press  ) +  utton move the pick-up to outside track, or  – 0  button to inside track.
5. To exit from this mode, perform as follows:

1) Move the pick-up to the most inside track.
2) Press three buttons in the same manner as step 2.

Note:
• Always move the pick-up to most inside track when exiting from this mode.  Otherwise, a disc will not be unloaded.
• Do not run the sled motor excessively, otherwise the gear can be chipped.

• A step of AM channels can be changed over between 9kHz and 10kHz.
Procedure:
1. Press  1/u  button to turn the set ON.
2. Select the function “TUNER”, and press  TUNER/BAND  button to select the BAND “AM”.
3. Press  1/u  button to turn the set OFF.
4. Press  ENTER/NEXT  and  1/u  buttons simultaneously, and the display of  fluorescent indicator tube changes to “AM 9k STEP” or “AM

10k STEP”, and thus the channel step is changed over.

Procedure:
1. Press three buttons  p  ,  ENTER/NEXT  , and  DISC 2  simultaneously.
2. LEDs and fluorescent indicator tube are all turned on.

Press  DISC 2  button, and the key check mode is activated.

3. In the key check mode, the fluorescent indicator tube displays “K 1 V0 J0”.  Each time a button is pressed, “K”value increases. However,

once a button is pressed, it is no longer taken into account.
“J” Value increases like 1, 2, 3 ... if rotating  JOG  dial in “+”  direction, or it decreases like 0, 9, 8 ... if rotating in “-” direction.
“V” Value increases like 1, 2, 3 ... if rotating  VOLUME  knob in “+”  direction, or it decreases like 0, 9, 8 ... if rotating in “-” direction.

4. To exit from this mode, press three buttons in the same manner as step 1, or disconnect the power cord.

This mode can be used for checking the operations of the CD player and tape deck.
• When problems occur;

Aging stops. If currently aging the tape deck, the state when aging stops will be displayed on the fluorescent indicator tube.

• When no problems;

Aging continues.

Preparations:
• Set the CD on the DISC1 tray.
• Insert a commercially available tape for recording (tapes which contents can be erased, etc.) in decks A and B.

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• The aging status is displayed on the fluorescent display tube. (Only when executing the tape deck section.)
• During the aging of the tape deck, the operations performed will be displayed. If operations ended abnormally, this will be displayed at the

fluorescent indicator tube.

Display of Operations

Operation

TAPE A AG-1

TAPE A AG-2

TAPE A AG-3

TAPE A AG-4

TAPE A AG-5

TAPE B AG-1

TAPE B AG-2

TAPE B AG-3

TAPE B AG-4

TAPE B AG-5

TAPE A REW

TAPE A FWD

TAPE A FF

TAPE A REV

TAPE A REW

TAPE B REW

TAPE B FWD

TAPE B FF

TAPE B REV

TAPE B REW

Timing of Ending

Shutoff

2 minute playback

20 seconds or shutoff

2 minutes playback

Shutoff

Shutoff

2 minute playback

20 seconds or shutoff

2 minute playback

Shutoff

• Operations are performed in the following sequence during aging

1. The CD tray rotates and disc 1 is selected.
2. Chucking is performed.
3. TOC is read.
4. Track 1 played back for 8 seconds.
5. The CD tray opens and closes again.
6. 1 to 5 is repeated.
7. After 12 minutes of aging, aging is switched to the tape deck.

1. The tape in deck A is rewound to the head.
2. The FWD side is played back for 2 minutes.
3. The tape is fast forwarded (FF) for 20 seconds. The following procedure is performed when the tape end is reached before the 20 seconds.
4. The REV side is played back for 2 minutes.
5. The tape is rewound to the head (REW).
6. The tape in deck B is rewound to the head.
7. The FWD side is played back for 2 minutes.
8. The tape is fast forwarded (FF) for 20 seconds. The following procedure is performed when the tape end is reached before the 20 seconds.
9. The REV side is played back for 2 minutes.
10. The tape is rewound to the head (REW).
11. Aging is switched to the CD player.

Aging of CD player (12 minutes)

Aging of deck A

Aging of deck B

Maximum about 12 minutes

Press the  p  button,  ENTER/NEXT  button, and  DISC SKIP/EX-CHANGE  button together.
When the aging mode is set, the CD roulette mark blinks. To exit the mode, press the  1/u  button and turn OFF the power.

The aging mode is executed in the following sequence.
If the function is set to “CD” when the aging mode is set, aging is performed starting from the CD player. When set to “TAPE A” or “TAPE
B”, aging is started from deck A.
If the function is set to others, aging will not be started until the function is switched to CD or TAPE.

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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

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.

L-CH
peak

R-CH
peak

screw
position

output
level

within
1 dB

L-CH
peak

R-CH
peak

screw
position

within 1dB

test tape
P-4-A100
(10kHz, –10dB)

main board
CN301
Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

level meter

set

+

–

main board
CN301
Pin 

2

 (GND)

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.