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3

Next, press the tracking button (+), (–) and change
the ATR signal 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 adjustment
driver (JiGDRiVERH-4) so that the ATR signal wave-
form changes nearly parallel.

4

If the tape is lifted or sunk from the helical lead
surface, the PB ATR signal waveform appears as
shown in Figure 4-30.

5

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

6

Finally, check tape crease near the reverse guide. If
tape crease is found, adjust tilt screw 45˚ counter
clockwise. Small tape crcase will appear at retain
guide after this adjustment finished.

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 ATR
signal waveform. (Note: At this time adjust so as to
get the maximum ATR signal waveform nearest the
A/C head position which has been set in case of X
value rough adjustment as stated in 4-17, 3- 

2

.)

4

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

5

Playback the self-picture-recorded tape, and check
the flatness of ATR signal 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 4-
17, 3-

2

).

PB ATR
Signal

4. A/C head X value adjustment

1

Fix A/C head arm screws 

1

 by the method described

in 4-15 "Replacement 3".

2

Playback the alignment tape (VROCPSV), and
shortcircuit between TP801 and TP802. As a result
the auto-tracking is automatically cancelled, so that
the X value adjustment mode is set.

Take-up side

Supply side

Take-up side

Adjustment

Supply side

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

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

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
ATR signal.

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
ATR signal.

When the tape is below the helical lead.

When the tape is above the helical lead.

1

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 set.

• Removal (Follow the order of indicated numbers.)
1. Unsolder loading motor wire and drum FFC .
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. Install the reel belt.
3. Solder loading motor wire and insert drum FFC .

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

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

2. 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 4-17 item 2.

2

2

1

4

5

4

D.D. rotor ass'y

D.D.stator ass'y

Upper drum

FFC

Capstan 
D.D. motor

Main chassis

1 

Reel belt

2

Solder drum FFC

Solder loading motor wire

1. Assemble the reverse guide lever 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 synchro gear.
5. Assemble the loading motor parts.

(Place the following parts in position in numerical order.)
(1)Pinch drive cam 

1

(2)Reverse guide spring 

2

(3)Reverse guide lever ass’y 

3

(4)Open guide 

4

• Replacement (Perform in the numerical order)

1

Remove the motor as stated in 4-19 D.D. motor replace-
ment.

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

4

2

3

1

Dot B

Dot A

Insert it into the 
groove of the shaft

Don't run up
on the spring

1

3

2

Synchro gear

From Top View

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

Matching point as shown below     .

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

position setting part as shown in figure     .

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

in figure     .

a

b

c

Loading arm (T)

Shifter

Insert point

Loading arm (T)

Loading arm (S)

Phase matting

*Not run on the 

sifter.

Sifter

Tension arm

a

c

b

Drum

Capstan D.D.
motor

(Bottom side of mechanism chassis)