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1. Set a torque gauge to zero on the scale. Place it on the

supply reel disk.

2. Switch from the FF mode to the STOP mode.
3. Disconnect the power cord.

Checking
Turn the torque gauge at a rate of about one turn/2 sec
in the CW direction/CCW direction with respect to the
supply reel disk so that the reel disk and torque gauge
pointer rotate at equal speed, and make sure that the
value is within the setting (CW direction: 4.9 to 13.7mN·m
(50 to 140gf·cm); CCW direction: 2.9 to 9.8mN·m (30 to
100gf·cm).

1. If the indication of torque cassette meter is lower than

the setting, shift the tension spring engagement to the
part A.

2. If the indication of torque cassette meter is higher than

the setting, shift the tension spring engagement to the
part B.

CCW: 4.9~13.7mN

⋅

m (50~140gf

⋅

cm)

CW:

3.9~10.8mN

⋅

m (40~110gf

⋅

cm)

CCW: 2.9~9.8mN

⋅

m (30~100gf

⋅

cm)

CW:

4.9~13.7mN

⋅

m (50~140gf

⋅

cm)

Tension arm

Tension spring

CW

CCW

CW

Supply reel disk

Torque gauge

Torque gauge

CCW

Take-up reel
disk

A

B

• Setting
1. Switch from the FF mode to the STOP mode.
2. Disconnect the power cord.
3. Set a torque gauge to zero on the scale. Place it on the

take-up reel disk.

• Checking
1. Turn the torque gauge at a rate of about one turn/2 sec

in the CCW direction/CW direction so that the reel disk
and torque gauge pointer rotates at equal speed and
make sure that the value is within the setting (CCW
direction: 4.9 to 13.7mN·m (50 to 140gf·cm), CW direc-
tion: 3.9 to 10.8 mN·m (40 to 110gf·cm).

2. Adjustment of the brake torque at the supply side and the

take-up side

• Unless the supply side brake torque or take-up side

brake torque is within the setting, clean the felt surface
of reel disk (supply, take-up) brake lever, check again
the brake torque.

• If value cannot be set within the setting yet, replace the

main brake ass'y or main brake spring.

• Replacement
1. Solder the removed PWB to the new head assembly.
2. Adjust the height from the A/C head plate (lower surface)

to the A/C head base to 10.8mm with slide calipers. (3
places of azimuth screw section, tilt screw section and
hight screw section)

(See the figure below.)

3. Align the left end of gear of A/C head plate with the

punched mark of chassis, tentatively tighten the screws

1

 and 

2

 so as to ensure smooth motion of A/C head

plate. Tentative tightening torque must be 0.15 to 0.20
N·m (1.5 to 2.0kgf·cm).

1. Remove the cassette housing control assembly.
2. In unloading state unplug the power cord.

• Removal
1. Remove the screws 

123

, Azimuth screw, Tilt screw.

2. Unsolder the PWB fitted to the A/C head.
Notes:
1. When replacing, never touch the head. If you touched,

clean with the cleaning liquid.

2. When removing the screw 

3

, take care so that the

spring may out.

New A/C head ass'y

A/C head PWB

2

Spring

1

Solder

❈

Never touch the head

10.8mm

10.8mm

Azimuth screw

Height screw

Tilt  screw

A/C head base

Note:
1. If the screws 

1

 and 

2

 are tighten tentatively too loose,

the azimuth and height of A/C head may change when
they are finally tightened. Therefore care must be taken.

2. After completion of A/C head be sure to adjust tape

running. (Execute the running adjustment by the method
described in Page 20, 21.)

Punched line mark on chassis

Left end of A/C head plate gear

1

2

3

Height screw

3

500g

Height screw

Azimuth screw

Tilt screw

Cassette tape

Mechanism chassis

Tape

0.3mm

A/C head

• Adjustment
Adjust the height screw

 

visually so that the control head is

visible 0.3mm below the bottom of the tape.

1. Set the cassette tape in the unit.
2. Press the PLAY button to put the unit in the playback

mode.

3. Roughly adjust the height of the A/C head by turning the

height screw until the tape is in the position shown
below.

1. Adjust the height from the mechanism chassis to the

reverse guide lower flange to 13.38 mm, using the
reverse guide height adjustment jig, in tape loading
state. (Refer to Figure 4-28 (a) (b).)

3. Set the tape, and check for tape crease near the reverse

guide in the playback mode.
If crease is found, turn the reverse guide adjustment nut
to remove crease. (As for crease check refer to Figure 4-
30.)

2. Rotate counterclockwise the reverse guide height ad-

justment nut 1/10 turn. (For height adjustment use the
reverse guide height adjustment box driver (JiGDRiVER
11055)).

13.38mm

Box driver

Height adjusting nut

500g

Capstan
motor shaft

Mechanism
chassis

Reverse guide

An example of
crease near the
reverse guide

Weight  to
prevent float (500g)

Fixing guide

* Check for crease from the A direction.

CCW

A

Reverse guide height
adjusting jig

Reverse guide height
adjusting jig

Reverse guide

Mechanism
chassis

Weight  to prevent
float (500g)

1. Tape run rough adjustment

1

Remove the cassette housing control assembly.

2

After shortcircuiting TP801 provided at the center
(facing to the main PWB), plug in the power cord.

3

Check and adjust the position of the tension pole.
(See page 15.)

4

Check and adjust the video search rewind back
tension. (See page 15.)

5

Connect the oscilloscope to the test point for PB
CHROMA envelope output (TP201). Set the syn-
chronism of the oscilloscope to EXT. The PB
CHROMA signal is to be triggered by the head
switching pulse (TP202).

6

Set the alignment tape (VROCPSV) to play. (Put a
500g weight on the cassette tape to prevent lift of
cassette tape.)

Notes:
1. Previously set the tracking control in the center position,

and adjust the envelop waveform to maximum with X
value adjustment nut. Thereby the tape run rough ad-
justment is facilitated.

2. Especially the outlet side envelope waveform must have

higher flatness.

500g

7

Press the tracking button (+), (–) and change the
envelope waveform from max to min and from min to
max. At this time make sure that the envelope
waveform changes nearly parallel.

8

Unless the envelope waveform changes nearly par-
allel, adjust the height of supply side and take-up
side guide roller so that the envelope waveform
changes nearly parallel. (For envelop adjustment
procedure refer to Figure 4-35.)

9

Turn the tilt screw to remove the tape crease at the
fixing guide flange.
Playback the tape and check for tape crease at the
fixing guide flange.
(1) If there is no tape crease

Turn the tilt screw clockwise so that tape crease
appears once at the flange, and then return the tilt
screw so that the crease disappears.

(2) If there is tape crease

Turn counterclockwise the tilt screw so that the
tape crease disappears.
(Reference) If the tilt screw is turned clockwise
crease appears at the lower flange.

Guide roller

Weight of 500g

Cassette Tape

2. Adjustment of A/C head height and azimuth

1

Perform the initial setting of A/C head position by the
method stated in "Page 18 Replacement 3".

2

Connect the oscilloscope to the audio output termi-
nal.

3

Using the alignment tape in which 1 kHz linear audio
signal has been recorded, adjust the height screw so
as to get max audio output.

4

Using the alignment tape in which 6 kHz linear audio
signal has been recorded, adjust the azimuth screw
so as to get max audio output.

5

Repeat the above adjustment steps 

3

 and 

4

  a

couple of times. Finally take the step 

4 

again.

For X value adjustment
Adjust the X value, turning the gear-
type screwdriver.

3. Tape run adjustment

1

Connect the oscilloscope to PB CHROMA envelope
output test point, set oscilloscope sync to EXT,
trigger-input the PB CHROMA signal (head switch-
ing pulse).

2

Rough adjustment of X value
Tentatively fix A/C head arm screws 

1

 and 

2

 by the

method described in Page 18 "Replacement 3".
Playback the alignment tape (VROCPSV) and
shortcircuit TP802. As a result the auto-tracking is
automatically cancelled, so that the X value adjust-
ment mode is set.
Move the A/C head with the X value adjustment gear
driver (JiGDRiVER-6) by the method shown in Fig-
ure 4-33, and adjust the A/C head so as to get the
maximum envelope waveform. (Note: When the A/
C head is adjusted, adjust so that the maximum
envelop waveform is obtained nearest the position
of initial setting made in Page 18.)