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— 5 —

[Fluorescent Indicator Tube, LED All Lit, and Key Check Mode]
1. When the plug is inserted into the outlet while pressing the

MEMORY SCAN  button, the fluorescent indicator tube and
LED will light up completely.

2. The mode changes as follows each time the  BAND  button and

WOOFER ON/OFF  button are pressed together after 1.

Sequence of Service Modes

*1 For checking if the fluorescent indicator tube and LED are lit

completely

*2 Model name and destination are shown in the destination display

mode.

*3 When the KEY check mode is set, “KEY 0”is displayed on the

fluorescent indicator tube. Each press of the button is counted.
(This excludes the  

1/u  button)

Buttons pressed once will not be counted when pressed again.
When all keys are pressed, “KEY END” appears.

*4 When the AMP check mode is set, “AMP” is displayed on the

fluorescent indicator tube.
Select any desired mode by pressing the  TONE  or  CENTER
or  REAR  or  WOOFER  button.  After a mode is selected,
press any of the  DOLBY  or  HALL  or  SIMULATED  button
as shown below to change the amplification level.

3. To exit the test mode, press the  

1/u  button, or press the p

(STOP) button of the deck A during the modes except the key
check mode.

[TC test mode]
1. Insert a playback tape into the deck A and a record tape into

the deck B.

2. While the power cable is disconnected from AC outlet, press

the  

1/u   switch.

3. While pressing the DUBBING SPEED HIGH button, connect

the power cable to the AC outlet.

Audio dubbing from deck A to Deck B starts.
When the  

0  button or the  )  button (during reverse

recording) of the deck B is pressed during dubbing, the tape
returns to the recording start point and playback starts.
When the  DUBBING SPEED HIGH  button is pressed during
dubbing, the high speed dubbing is performed.

[TC aging mode]
1. Turn on the main power.
2. Press the  TAPE  button. Insert a playback tape into the deck

A and a record tape into the deck B.

3. Set the  DIRECTION  switch to        .
4. Press the  WOOFER  and  

p (STOP) button of the deck A at

the same time to enter the aging mode.

TONE

CENTER

REAR

WOOFER

DOLBY

–10 dB

–15 dB

–15 dB

–24 dB

HALL

0 dB

0 dB

0 dB

0 dB

SIMULATED

+10 dB

+6 dB

+6 dB

+8 dB

Fluorescent Indicator
Tube and LED Check Mode

*1

Destination display mode

*2

•

 

 

Press the  BAND  button and 

   WOOFER ON/OFF  button at the same time.

KEY check mode

*3

•

 

 

Press the  BAND  button and 

   WOOFER ON/OFF  button at the same time.

•

 

 

Press the  BAND  button and 

   WOOFER ON/OFF  button at the same time.

AMP check mode

*4

•

 

 

Press the  BAND  button and 

   WOOFER ON/OFF  button at the same time.

These operations are repeated.

5. How to exit the TC aging mode.

Press any keys related to the TC deck.

[Backup Clear Mode]
1. While pressing the  DOLBY  key, connect the power cable to

the AC outlet. All preset data is cleared.

Deck A rewinds (REW) up to the tape top,
Deck B rewinds (REW) up to the tape top,
Deck A plays back (FWD) for one minute, then stops (STOP) 
momentarily,
Deck A plays back (FWD) for three minutes,
Deck A runs in fast forward (F. FWD) up to tape end,
Deck A plays back (REV) for one minute, then stops (STOP) 
momentarily,
Deck A plays back (REV) for three minutes,
Deck A runs in fast reverse (REV) up to tape top,
Deck B plays back (FWD) for one minute, then stops (PAUSE) 
momentarily,
Deck B records (FWD. RECORD) for three minutes,
Deck B runs in fast forward (F. FWD) up to tape end,
Deck B plays back (REV) for one minute, then stops (PAUSE) 
momentarily,
Deck B records (REV. RECORD) for three minutes,
Deck B runs in fast reverse (REV) up to tape end,   

<Repeat>

— 6 —

1.

Clean the following parts with a denatured-alcohol-moistened
swab:

record/playback head

pinch roller

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.

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

5.

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

DECK  SECTION

0 dB=0.775V

1.

Demagnetize the record/playback head with a head
demagnetizer.  (Do not bring the head demagnetizer close to
the erase head.)

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 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.

8.

Set  to  test  mode.   (While  pressing  the  DUBBING  SPEED
  HIGH   button, insert the AC outlet.)

•

Test Tape

  Perform this adjustments for both decks. Remove the covers

of cassette holders.

Procedure:
1.

Mode:  Playback (FWD)

Forward

CQ-102C

36 to 61g•cm

(0.50 to 0.84 oz•inch)

Forward

CQ-102C

2 to 6g•cm

Back Tension

(0.026 to 0.082 oz•inch)

Reverse

CQ-102RC

36 to 61g•cm

(0.50 to 0.84 oz•inch)

Reverse

CQ-102RC

2 to 6g•cm

Back Tension

(0.026 to 0.082 oz•inch)

FF, REW

CQ-201B

61 to 143g•cm

(0.85 to 1.98 oz•inch)

Forward

CQ-403A

more than 100 g

(3.53 oz•inch)

Reverse

CQ-403R

more than 100 g

(3.53 oz•inch)

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0dB

Tape Speed Adjustment

P-4-L300

315 Hz, 0dB

Level Adjustment

set

rear panel

VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

Screw
position

L-CH
peak

within
1dB

output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

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.

— 7 —

3.

Mode:  Playback (FWD)

4.

Repeat steps 1 to 3 in playback (REV) mode.

5.

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

Adjustment Location: Record/Playback Head (Deck A and B).

Procedure:
Mode:  Playback (FWD)

Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within adjustment
level as follows.
Adjustment Level:

VIDEO1 AUDIO OUT 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

set

test tape
P-4-A100
(10kHz, –10dB)

oscilloscope

L

R

V

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

rear panel

VIDEO1
AUDIO OUT connector

H

+
–

level meter

set

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

rear panel

VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)

Note: Start the Tape Speed adjustment as below after setting to the

test mode.

Procedure:
Mode:  Playback (FWD)

1.

Insert the WS-48B into the deck A and the blank tape into the
deck B.

2.

Press the REC button and

· button on the deck B.  Then

the deck B is at recording mode.

3.

Set the deck A to playback mode.

4.

Press the DUBBING SPEED  HIGH  button in playback mode.
Then at high speed mode.

5.

Adjust RV652 on the AUDIO board do that frequency counter
reads 6,000 

±

 180 Hz.

6.

Press the DUBBING SPEED  NORMAL  button in playback
mode.
Then at normal speed mode.

7.

Adjust RV651 on the AUDIO  board so that frequency counter
reads 3,000 

±

 90 Hz.

8.

Frequency difference between deck A and deck B the beginning
of the tape should be within 

±

 1.5 %.

Adjustment Location:  AUDIO board

W.RMS (JIS) within 0.3%
(test tape: WS-48B)

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

frequency counter

rear panel

VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)

Fowerd

side

Reverse

side

Adjustment screws

— 8 —

Procedure:
1.

Mode:  Record

2.

Mode:  Playback

Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV511 (L-
CH) and RV521 (R-CH) on the main board to repeat steps 1 and 2.
Adjustable limits:

VIDEO 1 AUDIO OUT level : 47.3 to 53.1 mV

(–24.3 to –23.3 dB)

Adjustment Location:  MAIN board

+
–

set

recorded
portion

level meter

rear panel

VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)

IC302

IC501

J101

J102

CN501

CN502

CN102

CN301

CN302

RV511
RECORD LEVEL
(L-CH)

RV521
RECORD LEVEL
(R-CH)

RV301
RV401

L
R

PB LEVEL

— DECK B —

— DECK A —

(NORMAL)

RV651

(HIGH)

RV652

PB

LEVEL

RV311

RV411

R

L

TAPE SPEED

R

L

RECORD

BAIS

RV441 RV341

set

VIDEO 1 IN connector (L: L-CH)

(R: R-CH)

315 Hz, 50 mV (–23.8 dB)

blank tape
CS-123

600 

Ω

attenuator

AF OSC

rear panel

[MAIN  BOARD] (Component Side)

[AUDIO  BOARD]  (Conductor Side)

Procedure:
1.

Mode:  Record

2.

Mode:  Playback

Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV341 (L-
CH) and RV441 (R-CH) on the AUDIO board to repeat steps 1 and 2.
Adjustable limits: Playback output of 315 Hz to playback output

of 10 kHz:  ±0.5 dB

Adjustment Location: AUDIO board

+
–

set

recorded
portion

level meter

rear panel

VIDEO1
AUDIO OUT connector
(L: L-CH)
(R: R-CH)

attenuator

set

VIDEO 1 IN connector (L: L-CH)

(R: R-CH)

1) 315 Hz
2) 10 kHz

50 mV (–23.8 dB)







600 

Ω

blank tape
CS-123

AF OSC

rear panel