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– 5 –

4

lag

5

mechanism deck
(TCM-9700HLD)

1

connector
(CN351)

2

two screws
(BVTP3 

×

 8)

1

connector
(CN803)

1

connector
(CN804)

3

two screws
(BVTP3 

×

 8)

6

power thansformer
(T901)

8

connector board

!º

four screws
(BVTP3 

×

 8)

9

screw
(BVTP3 

×

 10)

!¡

audio board

3

wire (flat type) (15 core)
(CN711)

2

connector
(CN351)

1

power cord
(CN901)

5

connector
(CN701)

7

two connectors
(CN713, 715)

4

four screws
(BVTT3 

×

 6)

– 6 –

2

two claws

A

tray

3

tray (A) ass’y

tray (A) ass’y

1

Rotate the  gear ass’y in direction
arrow 

A

 to up the tray.

1

six screws
(BVTT2.6 

×

 8)

5

three step screws
(MOTOR)

6

motor (HK) ass’y
(M902)

3

Remove the belt to position
figure the hang.

2

mechanism deck

4

Remove the solders
of motor (M902).

– 7 –

1. Clean the following parts with a denatured-alcohol-moistened

swab:

record/playback/earth head pinch roller
rubber belts

capstan

idlers

2. Demagnetize the record/playback head with a head demagne-

tizer. (Do not bring the head demagnetizer close to the erase
head.)

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.

1. The adjustment should be performed in the publication.

(Be sure to male playback adjustment at first.)

2. The adjustments and measurement should be performed for

both L-CH and R-CH.

•

Switch position
DOLBY NR switch

: OFF

DIRECTION switch

: 

A

•

Standard record position
Deliver the standard input signal level to input jack and set
the REC LEVEL (RV301) control to obtain the standard
output signal level as follows.

set

AF OSC

attenuator

600 

Ω

10 k 

Ω

LINE IN

+
–

LINE OUT

47 k 

Ω

level meter

source impedance

10 k

Ω

input signal level

0.5 V (– 3.8 dB)

load impedance

47 k

Ω

output signal level

0.5 V (– 3.8 dB)

P-4-A100

10 kHz, – 10 dB

Azimuth Adjustment

P-4-L300

315 Hz,

0 dB

PB Level Adjustment

WS-48B

3 kHz,

0 dB

Tape Speed Adjustment

CQ-102C

30 – 65 g•cm

FWD

(0.42 – 0.90 oz•inch)

FWD

1.5 – 6 g•cm

Back tension

(0.021 – 0.083 oz•inch)

CQ-102RC

30 – 65 g•cm

REV

(0.42 – 0.90 oz•inch)

REV

1.5 – 6 g•cm

Back tension

(0.021 – 0.083 oz•inch)

70 – 130 g•cm

FF, REW

CQ-201B

(0.98 – 1.80 oz•inch)

With the POWER turned OFF, short the test point CN801 (2P) on
the SYSTEM CONTROL board (making IC801 pin !º “L”) and
turn the POWER ON. Thus, the TEST mode will be activated.
If a recording is done in the TEST mode, the REC MEMORY
mode becomes active where the tape is rewound by the amount of
recording when a rewinding is executed after recording.
After adjustment, make the CN801 (2P) open to release the TEST
mode.

– 8 –

Procedure:
1. Mode: REV playback

+
–

set

47 k 

Ω

LINE OUT

level meter

test tape
P-4-A100
(10 kHz, – 10 dB)

2. Turn the adjustment screw for the maximum output levels. If

these levels do not match, turn the adjustment screw until both
of output levels match together within 1 dB.

Procedure:
Mode: FWD playback

+
–

set

LINE OUT

frequency counter

test tape
WS-48B
(3 kHz, 0 dB)

47 k 

Ω

1. Set to FWD playback mode.
2. Adjust RV801 so that the frequency counter reading becomes

3,000 ± 90 Hz.

3. Confirm that the deviation between tape top and tape end is

within 3%.

Adjustment Location: SYSTEM CONTROL board (See page 10)

Sample Value of Wow and flutter: 0.3% or less W.RMS

(WS-48B)

Procedure:
Mode: FWD playback

Screw
position

L-CH
peak

within
1dB

output
level

L-CH peak

R-CH peak

within
1dB

angle

R-CH
peak

3. Phase Check

Mode: REV playback

+
–

V

H

+

–

Screen pattern

Good

Wrong

in phase 45

°

90

°

135

°

180

°

LINE OUT

set

R-CH

L-CH

47 k 

Ω

47 k 

Ω

oscilloscope

test tape
P-4-A100
(10 kHz, –10 dB)

4. Set in the FWD mode and repeat the step 1 to 3.
5. After the adjustment, lock the screw with locking compound.

Adjustment Location: Record/Playback head































FWD side

REV side

Adjustment screw

+
–

set

LINE OUT

47 k 

Ω

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

level meter

Adjust RV151 (L-CH) and RV251 (R-CH) so that the reading on
level meter meets the adjustment limits below.

LINE OUT level: – 7.7 ± 0.5 dB (0.301 to 0.338 V)
Level difference between channels: within 2 dB

Check that the LINE OUT level does not change even if Playback
and Stop operation is repeated several times.

Adjustment Location: AUDIO board (See page 10)