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26

If the nonvolatile memory data is abnormal, “E001 MEMORY NG” will be displayed so that the MD deck does not continue operations. In

this case, set the test mode promptly and perform the following procedure.

Procedure:
1. Enter the MD test mode.
2. Normally a message for selecting the test mode will be displayed. However if the nonvolatile memory is abnormal, the following will be

displayed “INIT EEP?”.

3. Press the

x

(MD) and Z (MD) buttons simultaneously.

4. Press the

. “R”

or

 > “R”

button to display “MDM-7B”.

5. Press the

REC MODE

button. If the nonvolatile memory is successfully overwritten, the normal MD test mode will be set and a message

to select the MD test mode will be displayed.

Before performing repairs, perform the following checks to determine the faulty locations up to a certain extent.
Details of the procedures are described in “Section 6  Electrical Adjustments”.

• 0.9 mW power

Specified value : figure1

• 7.0 mW power

Specified value : figure2

Iop (at 8.4mW)

• Labeled on the optical pick-up

Iop value ± 10mA

• Unsatisfactory if displayed as “NG : XXXX”NG

(XXXX are arbitrary numbers)

• Unsatisfactory if displayed as “T=@@ (##) [NG]”

NG
(@@, ## are both arbitrary numbers)

Laser power check
(6-2 : See page 32)

Auto check
(6-7 : See page 33)

Temperature
compensation
offset check
(6-1 : See page 32)

• Clean the optical pick-up
• Adjust again
• Replace the optical pick-up

• Replace the optical pick-up

• Replace the optical pick-up

• Check for disconnection of the circuits around

D101 (BD board)

• Check the signals around IC101, IC151, CN102,

CN103 (BD board)

Note:
The criteria for determination above is intended merely to determine if satisfactory or not, and does not serve as the specified value for adjustments.
When performing adjustments, use the specified values for adjustments.

Figure1:

SPECIFIED VALUE

KMS-260B
KMS-260E

0.85 to 0.91 mW
0.90 to 0.96 mW

Figure2:

SPECIFIED VALUE

KMS-260B
KMS-260E

6.8 to 7.2 mW
7.0 to 7.5 mW

[CD SERVO Test Mode]
• Use this mode when checking CD servo.

Procedure:
1.

Press  ?/1  button to turn the set ON.

2.

Select the function “CD”.

3.

Press three buttons  M  (TAPE),  SYNCHRO REC  and  >  (MD) simultaneously.

4.

Press the appropriate button for the following tests.

Button

Function Button

Function

Z(CD)

TEST 1

PLAY MODE DIRECTION

TEST 6

x(CD)

TEST 2

u(CD)

TEST 7

>

TEST 3

x(MD)

TEST 8

.

TEST 4

x(TAPE)

TEST 9

REPEAT TEST 5

5.

To exit from this mode, turn off the set.

27

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
demagnetizer.

3.

Do not use a magnetized screwdriver for the adjustments.

4.

The adjustments should be performed with the rated power
supply voltage unless otherwise noted.

Note: Standard Volume Point is +10 dBs at SPEAKER Output Level (6

Ω

load resistance) during playbacking P-4-L300 Test Tape.
(DSG OFF, TREBLE/BASS CENTER)

Procedure:
1.

Mode : Playback

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

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
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
(10kHz, –10dB)

SJ301
 SPEAKER
Output Terminal

level meter

set

+

–

6 

Ω

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

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

FWD

FWD
back tension

REV

REV
back tension

FF/REW

FWD tension

REV tension

28

4.

After the adjustments, apply suitable locking compound to the
parts adjusted.

3.

Mode: Playback

test tape
P-4-A100
(10kHz, –10dB)

oscilloscope

set

Waveform of oscilloscope

in phase

45

°

90

°

135

°

180

°

good

wrong

GND

R-ch

L

R

SJ301
 SPEAKER
Output Terminal

6 

Ω

6 

Ω

1.

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

2.

Insert a tape into deck, press the  z REC  (TAPE) button, and
then press the  X  (TAPE) button to start recording.

3.

Mode: Record

1.

MODE : Playback.

test tape
P-4-L300
(315Hz, 0dB)

SJ301
 SPEAKER
Output Terminal

frequency
counter

set

6 

Ω

4.

Mode: Playback

5.

The playback output  level should be –4.5 ±3 dB (60 Hz),
1 ±3 dB (8 kHz) and –3 ±3 dB (10 kHz).

AF OSC

     PJ301
ANALOG IN
1) 60 Hz
2) 5 kHz
3) 10 kHz

blank tape
CS-123

set

attenuator

600 

Ω

109 mV (–17 dB)

recorded
position

level meter

set

6 

Ω

SJ301
 SPEAKER

(Top view)

Adjustment point

2.

Insert the WS-48B into deck.

3.

Press the  Y  button of deck.

4.

Check the reading of frequency counter becomes 3000 ± 90
Hz.

W.RMS (JIS) less than 0.35%
(test tape: WS-48B)

29

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
following checks.

Procedure :
1. Connect oscilloscope to TP (RFAC).
2. Turned Power switch on.
3. Load a disc (YEDS-18) and playback.
4. Confirm that oscilloscope waveform is clear and check 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.

Procedure:
1.

Connect oscilloscope to TP (TE) and TP (DVC 1.65V).

2.

Turned Power switch on.

3.

Load a disc (YEDS-18) and playback the number five track.

4.

Press the  u  button. (Becomes the 1track jump mode.)

5.

Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.

Specification level:      x 100=less than ±22%

TP(RFAC)

TP(DVC 1.65V)

CD BOARD

oscilloscope

VOLT/DIV : 200mV
TIME/DIV : 500ns

level : 1.1 

±

 0.3Vp-p 

CD BOARD

Oscilloscope

TP(TE)

TP(DVC 1.65V)

0V

Center of
waveform

B

Symmetry

A (DC voltage)

level=1.3 

±

0.6Vp-p

A
B

Procedure :
1.

Connect frequency counter to TP (XPCK) with lead wire.

2.

Turned Power switch on.

3.

Put the disc (YEDS-18) in to play the number five track.
Confirm that reading on frequency counter is 4.3218MHz.

+
–

frequency counter

CD BOARD

TP (XPCK)

TP
(DVC 1.65V)

TP
(TE)

IC101

IC103

TP 
(XPCK)

TP 
(RFAC)