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13

2

portion A of tray (sub)

1

stocker section

3

two step screws

3

two step screws

Hook the portion A of tray (sub)
to the slider (selection).

potion A
of tray (sub)

sticking of
slider (selection)

3

three screws
(BVTP M2.6)

2

Insert the gear (eject)
under the gear (LD
deceleration).

1

Insert the portion A of
chassis (mold B) section
into the portion B of
slider (selection).

gear (LD deceleration)

portion A

portion B of
slider (selection)

14

Procedure:
1. Press the

?

/

1

button to turn the power ON.

2. Press three buttons of

s

(DECK B),

A

(DISC 1), and

[DISC 5]

 simultaneously.

3. LEDs are all turned on.

Press the

G

(CD) button, and the key check mode is activated.

LEDs are all OFF.

4. When a button is pressed, the LED near the pressed button

blinks or lights up.
Also, if all buttons are pressed, all LEDs light up (not blink).

5. To release from this mode, press three buttons in the same

manner as step 2, or remove the power cord.

• This mode moves the optical pick-up to the position durable to

vibration. Use this mode when returning the set to the customer
after repair.

Procedure:
1. Press the

?

/

1

button to turn the power ON.

2. Press the

s

(DECK B) and 

[DISC 1]

 buttons simultaneously.

3. A message “LOCK” is displayed on the liquid crystal display

of the STR-NX300, and the CD delivery mode is set.

• If connected to the STR-NX300, the mode also acts as the STR-

NX300 amplifier test mode.

Procedure:
1. Press the

?

/

1

button to turn the power ON.

2. Press three buttons of

s

(DECK B),

A

(DISC 1), and

S

(CD)

simultaneously.

3. On liquid crystal display of the STR-NX300, the disc calen-

dar blinks, and “ALC OFF” is displayed, then the function
which was set before the test mode became active is displayed.

4. The automatic level control of the tape deck is in OFF status,

but while the

s

(CD) and 

[REC PAUSE/START]

 buttons are

pressed during recording, automatic level control goes in ON
status.

Procedure:
1. Turn on the Power switch on the power feed jig.
2. Press three buttons of s (DECK B), A (DISC 1),

and s (CD) simultaneously.

3. The G (CD) and S (CD) LEDs blink, and then pressing G

(CD), G / g (DECK A), or G / g (DECK B) button can
make each play possible.

4. Also, the other functions are enabled by pressing two buttons

simultaneously.
A combination of respective functions and buttons is as fol-
lows.

function

button

CD AMS –

s (DECK A), S (CD)

AMS +

s (DECK A), s (CD)

FR

s (DECK B), S (CD)

FF

s (DECK B), s (CD)

Deck-A REW/AMS –

s (CD), g (DECK A)

FF/AMS +

s (CD), G (DECK A)

Deck-B REW/AMS –

s (CD), g (DECK B)

FF/AMS +

s (CD), G (DECK B)

 Check that CD/TC signal change switch of relay connector jig is

set to the TC position.

On this mode, the data of the color-bars signal as a picture signal
and the 1 kHz sine wave signal as a sound signal are output by the
mechanism controller (IC505) for the video CD signal check.
When measurement of the voltage and waveform on the VIDEO
board, perform it in this mode.
For reference, the color-bars signal can be observed at J502
(VIDEO OUT) and the sound signal can be observed at J101
(VIDEO/MD (AUDIO) OUT) (STR-NX300) using an oscillo-
scope.
Procedure:
1. Short the both ends of the land of SL503 of the VIDEO board.
2. Turn the power on. Press the 

[FUNCTION]

 button to select

CD.

3. The color-bars appears when the CD is in stop status, and it

disappears when the CD goes in play status.

4. After measuring, remove the lead wire connected.

CN501

SL501

SL502

SL503

CN502

IC505

15

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

(0.03 – 0.08 oz • inch)

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.03 – 0.08 oz • inch)

71 to 143 g • cm

(0.99 – 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

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 demagne-

tizer.

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 ad-
justment 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 other-

wise specified.

8. Set to  the DOLBY NR OFF.
9. Set to the test mode. (See page 14)
10. When using the PFJ-1, disconnect a flat cable between CN111

(MAIN board) and CN502 (VIDEO board).

• Test Tape

 Perform this adjustments for both decks

Procedure:
1. Mode: Playback

0 dB=0.775 V

AUDIO OUT jack

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

PFJ-1

or

STR-

NX300

set

Tape

Signal

Used for

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

16

Mode: Playback

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

G

(DECK B) button.

3. Press the 

[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 the 

[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
Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

(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 specified
value as follows.

AUDIO OUT jack PB 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

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. Repeat step 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the

pats adjusted.

Adjustment Location: Playback Head (Deck A).

Record/Playback/Earth Head (Deck B).

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

test tape
P-4-A100
(10 kHz, –10 dB)

oscilloscope

AUDIO OUT (R) jack

L-CH

R-CH

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

AUDIO OUT (L) jack

L-CH

R-CH

PFJ-1

or

STR-

NX300

set

forward

reverse

Open the cassette holder 
and unhock six claws of 
the sub panel (TC2)
with tweezers or something, 
then remove the sub panel (TC2).

+
–

AUDIO OUT jack

test tape
WS-48B 
(3 kHz, 0 dB)

frequency counter

set

STR-

NX300

+
–

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

level meter

AUDIO OUT jack

PFJ-1

or

STR-

NX300

set