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• Remove the mechanism from the set.

• Removal (Follow the order of indicated numbers.)
1. Unsolder loading motor wire and drum FFC to remove

them from Capstan D.D. motor control PWB.

2. Remove the reel belt 1.
3. Remove the three screws 2.

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.

2. Install the reel belt 1.
3. Solder loading motor wire and drum FFC to the capstan

D.D. motor control PWB.

Notes:
1. After installing the capstan D.D. motor, be sure to rotate

the capstan D.D. motor and check the movement.

2. Load a tape, and check for wrinkles on the tape near the

reverse guide in the playback mode. Make adjustments
according to "2. Adjustment of A/C head height and
azimuth" in "8-19. ADJUSTMENT OF TAPE DRIVE
TRAIN". If wrinkles are found, make adjustments
according to "3. Tape run adjustment" in the same
section.

3. When soldering the FFC and the loading motor wires, do

not scatter solder over the magnet of the capstan rotor.

Main chassis

Solder drum FFC

Solder loading
motor wire

Capstan 
D.D. motor

2

1 Reel belt

Capstan D.D. motor
control PWB

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.

2

3

1

4

5

4

Drum D.D. rotor ass'y

Drum D.D.stator ass'y

Upper drum

FFC

•   Replacement (Perform in the numerical order)
1 Remove the motor as stated in 8-21 Replacement of

Drum D.D. motor.

2 Remove the drum earth brush ass’y 2.
3 Remove the upper and lower drum assembly from main

chassis 1.

4 Remove the drum FFC holder 3.

[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.

2

1

3

Lower drum bottom side

1. Assemble the reverse guide lever and pinch drive cam.
2. Mounting the sifter (on the back of the mechanism

chassis).

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

nism chassis).

4. Assemble synchro gear (on the back of the mechanism

chassis).

5. Assemble the loading motor parts.

(Assemble the following parts in numerical order.)
(1)Pinch drive cam 1
(2)Reverse guide spring 2
(3)Reverse guide lever ass’y 3
(4)Open guide 4

4

2

3

1

B

A

Insert it into the 
groove of the shaft

Don't run up
on the spring

1

3

2

Synchro gear

The hole is in 
the direction of 
Synchro gear shaft.

From Top View

Loading arm (T)

Sifter

Insert point

Loading arm (T)

Loading arm (S)

Phase matching

*Not run on the 

sifter.

Sifter

Tension arm

a

c

b

Drum

Capstan D.D.
motor

(Bottom side of mechanism chassis)

* Remove the SUP/TU main brake before installation.

1. Make sure that the loading arm T and S are at the Phase-

Matching point as shown below     .

2. Fix the sifter position setting part to the roading arm T

position setting part as shown in figure     .

3. Make sure tension arm not run on the sifter as shown in

figure     .

a

b

c

1. Before installing the master cam, make sure that the

sifter is at initial position. (Right side from bottom view)

2. Place the master cam by pushing in so that the long hole

of the master cam comes to the front side as shown
below.

3. Fix the E-ring.
4. Adjust the master cam and pinch drive cam, fix the

synchro gear in correct position.

Note:
See the figure below for the phase matching between the
master cam synchro gear and pinch drive cam.
• Phase alignment of the master cam and the synchro

gear;
Align the wide tooth space and the composite tooth.

• Phase alignment of the synchro gear and the pinch drive

cam;
Adjust the teeth so as to orient the rib of the synchro gear
and the hole of the pinch drive cam.

E-ring

Pinch Drive Cam

Synchro
gear

Phase
matching

Hole of Pinch Drive Cam

Master Cam

Phase
matching

Rib

Push in with this long hole
toward you. The sifter
moves slightly to the left.

• Replacement
Remove the loading motor, and install the replacement
loading motor as shown below.

The loading motor pressing-in must be less than 196N (20
kgf).
Adjust the distance between motor and pulley to 6.95
      mm.

+0

.  2

–0.15

6.95      mm

A part

Worm gear

+0

 - 0.15

Loading 
motor

To press the motor in, first 
receive it by portion A.

Apply grease

Worm gear

Apply grease

Apply grease

Apply grease

L-M-Block.

Worm wheel gear.

Leading connect gear.

*Apply grease to 

the tip as well.

Loading

motor.

Wire
   + : Red
   -  : White

Red

Insert

(