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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 16.)

4

Check and adjust the video search rewind back
tension. (See page 16.)

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 19 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 19 "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 19.)

3

Next, change the alignment tape to VROCPSV to
playback. Press the tracking button (+), (–) and
change the envelope waveform from max to min and
from min to max. At this time adjust the height of
supply and take-up side guide roller with the adjust-
ment driver (JiGDRiVERH-4) so that the envelope
waveform changes nearly parallel.

4

If the tape is lifted or sunk from the helical lead
surface, the PB CHROMA envelope waveform ap-
pears as shown in Figure 4-35.

5

Press the tracking button (+), (–) and make sure that
the envelope waveform changes nearly parallel.

6

Finally check tape crease near the reverse guide. If
tape crease is found, remove it as stated in Page 20
"HEIGHT ADJUSTMENT OF REVERSE GUIDE"
item 3.

3

Move the A/C head with the X value adjustment gear
driver by the method shown in Figure 4-33, and
adjust the A/C head so as to get the maximum
envelope waveform. (Note: At this time adjust so as
to get the maximum envelope waveform nearest the
A/C head position which has been set in case of X
value rough adjustment as stated in Page 21, 3- 

2

.)

4

Tighten finally the screws 

1

 and 

2

. Be sure to

tighten at first the screw 

1

 and then the screw 

2

.

Final tightening torque is 0.6N·m (If the screw 

2

 is

tightened first, the X value may deviate.)

5

Adjust the playback switching point (Refer to the
electric adjustment method.)

6

Playback the self-picture-recorded tape, and check
the flatness of envelope waveform and sound.

Notes:
When the A/C head X value adjustment is performed, be
sure to perform at first X value rough adjustment (refer to
Page 21, 3-

2

).

Take-up side

Supply side

Take-up side

Adjustment

Supply side

Supply side guide roller
rotated in clockwise
direction (lowers guide
roller) to flatten
envelope.

Take-up side guide roller
rotated in clockwise
direction (lowers guide
roller) to flatten
envelope.

Supply side guide roller
rotated in counterclock-
wise direction (raises
guide roller) to make the
tape float above the helical
lead. The supply
side guide roller is then
rotated in the clockwise
direction to flatten the
envelope.

Take-up side guide roller
rotated in counterclock-
wise direction (raises
guide roller) to make the
tape float above the
helical lead. The take-up
side guide roller is then
rotated in the clockwise
direction to flatten the
envelope.

When the tape is below the helical lead.

When the tape is above the helical lead.

1

2

PB CHROMA
Envelope

CH-1

CH-2

4. A/C head X value adjustment

1

Tentatively fix A/C head arm screws 

1

 and 

2

 by the

method described in Page 19 "Replacement 3".

2

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.

1. Set the ejection mode.
2. Withdraw the main power plug from the socket.

• Removal (Perform in numerical order.)
1. Disconnect the FFC cable 

1

.

2. Unscrew the D.D. stator assembly fixing screws 

2

.

3. Take out the D.D. stator assembly 

3

.

4. Unscrew the D.D. rotor assembly fixing screws 

4

.

5. Take out the D.D. rotor assembly 

5

.

Notes:
1. In removing the D.D. stator assembly, part of the drum

earth spring pops out of the pre-load collar.
Be careful not to lose it.

2. Install, so that the D.D. rotor ass'y and upper drum ass'y

mounting direction check holes align.
(Align the upper drum dent with the rotor hole.)

3. Be careful not to damage the upper drum or the video

head.

4. Protect the hole elements from shock due to contact with

D.D. stator or D.D. rotor ass'y.

5. After installation adjust the playback switching point for

adjustment of servo circuit.

• Remove the mechanism from the main PWB (refer to

Page 6 item 1. When removing the mechanism from the
main PWB").

1. Remove the reel belt 

1

.

2. Remove the slow brake lever 

2

.

3. Remove the three screws 

3

.

2

4

4

5

D.D. stator ass'y

D.D. rotor ass'y

Upper drum

3

1

FFC

Capstan D.D.
motor

Capstan D.D. motor
control PWB

3

1

Reel belt

2

Slow Brake lever

1. Taking care so that the capstan shaft does not contact

the mechanism chassis, set its position on the mecha-
nism chassis, and then install with the three screws.

2. Install the slow brake lever.
3. Install the reel belt.
Notes:
1. Before installing the capstan D.D. motor, confirm  whether

an acetate tape (ZTAPE120020E) is drawn on the back
of mechanism chassis.

2. After installing the capstan D.D. motor, be sure to

rotate the capstan D.D. motor and check the move-
ment.

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

reverse guide in the playback mode. Adjust the A/C
head and azimuth as stated in Page 21 Replacement
2. If crease is found, adjust as stated in Page 20
"HEIGHT ADJUSTMENT OF REVERSE GUIDE".

MechanismChassis from the back.

Stick an acetate tape on the 
projection part of the chassis.

Capstan Motor 
installation position.

1. Assemble the pinch roller assembly and pinch drive

cam.

2. Mounting the shifter (on the back of the mechanism

chassis).

3. Mounting the master cam (on the back of the mecha-

nism chassis).

4. Assemble the connection gear, slow brake and loading

motor parts.

(Place the following parts in position in numerical order.)
(1)Reverse drive lever 

1

(2)Reverse guide spring 

2

(3)Reverse guide lever ass’y 

3

(4)Reverse guide height adjusting nut 

4

(5)Pinch drive cam 

5

(6)Pinch roller ass’y 

6

(7)Open lever 

7

• Replacement (Perform in the numerical order)

1

Remove the motor as stated in Page 23 D.D. motor
replacement.

2

Remove the drum earth brush ass’y 

2

.

3

Remove the drum base 

3

 from the upper and lower

drum assembly 

1

.

[Cares when replacing the drum]
1. Be careful so that the drum earth brush is not lost.
2. Do not touch directly the drum surface.
3. Fit gently the screwdriver to the screws.
4. Since the drum assembly is an extremely precise as-

sembly, it must be handled with utmost care.

5. Make sure that the drum surface is free from dust, dirt

and foreign substances.

6. After replacing the drum  be sure to perform the tape

running adjustment.
After that, perform also the electrical adjustment.
• Playback switching point adjustment
• X-position adjustment and check
• Standard and x-3 slow tracking adjustment

7. After replacing the drum clean the drum.

7

4

3

2

6

1

5

2

1

3