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Reel Disk Height
Adjustment Jig
(JG024A)

Reel Disk

Master Plane (JG022)

(B)

10(+0.2, -0)mm

Height Adjustment Washer
2.6x4.7xT0.13
2.6X4.7xT0.25

(A)

(C)

Read the following NOTES before starting work.

•

Place an object which weighs between 450g~500g on
the Cassette Tape to keep it steady when you want to
make the tape run without the Cassette Holder. (Do not
place an object which weighs over 500g.)

1.
2.

3.

4.

Turn on the power and set to the STOP mode.
Set the master plane (JG022) and reel disk height
adjustment jig (JG024A) on the mechanism framework,
taking care not to scratch the drum, as shown in Fig. 1-
1-A.
While turning the reel and confirm the following points.
Check if the surface “A” of reel disk is lower than the
surface “B” of reel disk height adjustment jig (JG024A)
and is higher than the surface “C”. If it is not passed,
place the height adjustment washers and adjust to
10(+2, -0)mm.
Adjust the other reel in the same way.

Master Plane (JG022)

Reel Disk Height Adjustment Jig
(JG024A)

Fig. 1-1-A

Fig. 1-1-B

1.
2.

3.

Set to the PLAY mode.
Adjust the adjusting section for the Tension Arm
position so that the Tension Arm top is within the
standard line of Main Chassis.
While turning the S Reel clockwise, confirm that the
edge of the Tension Arm is located in the position
described above.

Fig. 1-2-A

Standard line of Main Chassis

Tension Arm

0.5mm (Adjusting range)

Fig. 1-2-B

Adjusting section for the
Tension Arm position

Tension Band

The Tension Arm top will
move to the inside direction
of the Main Chassis.

The Tension Arm top will
move to the outside direction
of the Main Chassis.

Bend

1.

2.

Load a video tape (E-180) recorded in standard speed
mode. Set the unit to the PLAY mode.
Install the tentelometer (JG185) as shown in Fig. 1-3.
Confirm that the meter indicates 20 

±

 2gf in the begin-

ning of playback.

• USING A CASSETTE TYPE TORQUE TAPE (JG100A)

1.

2.

3.

After confirmation and adjustment of Tension Post
position (Refer to item 1-2), load the cassette type
torque tape (JG100A) and set to the PLAY mode.
Confirm that the right meter of the torque tape indicates
50~90gf•cm during playback in SP mode.
Confirm that the left meter of the torque tape indicates
25~40gf•cm during playback in SP mode.

Video Tape

P1 Post

Guide Roller

Fig. 1-3

Tentelometer
(JG185)

1.

2.

Install the Torque Gauge (JG002F) and Adapter (JG002B)
on the S Reel. Set to the Picture Search (Rewind) mode.
(Refer to Fig.1-4-B)
Then, confirm that it indicates 120~180gf•cm.

If the torque is out of the range, replace the following parts.

Tape Running Mechanism is adjusted precisely at the
factory. Adjustment is not necessary as usual. When you
replace the parts of the tape running mechanism because
of long term usage or failure, the confirmation and adjust-
ment are necessary.

After adjustment, confirm and adjust A/C head.
(Refer to item 2-2)

Fig. 2-1-A

CH-1
Envelope
(TP103)

CH-1
Track

CH-2
Track

CH-2
SW Pulse (TP102)

Fig. 2-1-B

Entrance

Max

Exit

Max

A

B

A : B 

≥

 3 : 2

Install the Torque Gauge on the reel disk firmly. Press the
REW button to turn the reel disk.

(S Reel Brake) (Refer to Fig. 1-4-B)

1.

2.
3.

4.

Once set to the Fast Forward mode then set to the Stop
mode. While, unplug the AC cord when the Pinch Roller
Block is on the position of Fig. 1-4-A.
Move the Idler Ass’y from the S Reel.
Install the Torque Gauge (JG002F) and Adapter
(JG002B) on the S Reel. Turn the Torque Gauge
(JG002F) clockwise.
Then, confirm that it indicates 60~100gf•cm.

(T Reel Brake) (Refer to Fig. 1-4-B)

1.

2.
3.

4.

Once set to the Fast Forward mode then set to the Stop
mode. While, unplug the AC cord when the Pinch Roller
Block is on the position of Fig. 1-4-A.
Move the Idler Ass’y from the T Reel.
Install the Torque Gauge (JG002E) and Adapter
(JG002B) on the T reel. Turn the Torque Gauge
(JG002E) counterclockwise.
Then, confirm that it indicates 30~50gf•cm.

Fig. 1-4-A

The position at FF mode.

Stop at this position.

The position at
STOP mode.

Capstan DD Unit

Cassette Holder Ass’y

Cassette Opener

Pinch Roller Block

Fig. 1-4-B

Torque Gauge/Adapter
(JG002F/JG002B)

S Reel

T Reel

Torque Gauge/Adapter
(JG002E/JG002B)

Check item

1-4

Replacement Part

Idler Ass’y/Clutch Ass’y

S Reel side:

T Reel side:

S Reel/Tension Band/Tension
Connect/Tension Arm Ass’y
T Reel/T Brake Band//T Brake
Spring/T Brake Arm

1-5

Playback the VHS Alignment Tape (JG001C or JG001E).
(Refer to SERVICING FIXTURE AND TOOLS)
Connect CH-1 of the oscilloscope to TP103 (Envelope)
and CH-2 to TP102 (SW Pulse).
Press and hold the Tracking-Auto button on the remote
control more than 2 seconds to set tracking to center.
Trigger with SW Pulse and observe the envelope. (Refer
to Fig. 2-1-A)
When observing the envelope, adjust the Adjusting Driver
(JG005) slightly until the envelope will be flat.
Even if you press the Tracking Button, adjust so that
flatness is not moved so much.
Adjust so that the A : B ratio is better than 3 : 2 as shown
in Fig. 2-1-B, even if you press the Tracking Button to
move the envelope (The envelope waveform will begin to
decrease when you press the Tracking Button).
Adjust the PG shifter during playback.
(Refer to the ELECTRICAL ADJUSTMENTS)

1.

2.

3.

4.

5.

6.

7.

When the Tape Running Mechanism does not work well,
adjust the following items.

1.

2.

3.
4.

Playback the VHS Alignment Tape (JG001C or JG001E).
(Refer to SERVICING FIXTURE AND TOOLS)
Confirm that the reflected picture of stamp mark is
appeared on the tape prior to P4 Post as shown in Fig.
2-2-A.
a)

b)

Turn the screw 

2

 to set the audio level to maximum.

Confirm that the bottom of the Audio/ Control Head and
the bottom of the tape is shown in Fig. 2-2-C.
c)

When the reflected picture is distorted, turn the screw

1

 clockwise until the distortion is disappeared.

When the reflected picture is not distorted, turn the
screw 

1

 counterclockwise until little distortion is

appeared, then adjust the a).

When the height is not correct, turn the screw 

3

 to

adjust the height. Then, adjust the 1~3 again.

Fig. 2-2-A

Audio/Control Head

Reflected picture of
Stamp Mark

P4 Cap

Stamp Mark

Fig. 2-2-B

3

Audio/Control Head

2

1

4

Fig. 2-2-C

Audio/Control Head

Tape

0.25

±

0.05mm

Fig. 2-3

Envelope

(1)

CH-3
Audio

(2)

Confirm and adjust the height of the Reel Disk.
(Refer to item 1-1)
Confirm and adjust the position of the Tension Post.
(Refer to item 1-2)
Adjust the Guide Roller. (Refer to item 2-1)
Confirm and adjust the Audio/Control Head.
(Refer to item 2-2)
Connect CH-1 of the oscilloscope to TP102, CH-2 to
TP103 and CH-3 to HOT side of Audio Out Jack.
Playback the VHS Alignment Tape (JG001U or JG001V).
(Refer to SERVICING FIXTURE AND TOOLS)
Press and hold the Tracking-Auto button on the remote
control more than 2 seconds to set tracking to center.
Set the X Value adjustment driver (JG153) to the 

4

 of

Fig. 2-2-B. Adjust X value so that the envelope waveform
output becomes maximum. Check if the relation between
Audio and Envelope waveform becomes (1) or (2) of Fig.
2-3.

1.

2.

3.
4.

5.

6.

7.

8.

Connect CH-1 of the oscilloscope to TP102 and CH-2 to
the Hi-Fi Audio Out Jack.
Playback the VHS Alignment Tape (JG001R). (Refer to
SERVICING FIXTURE AND TOOLS)
Press and hold the Tracking-Auto button on the remote
control more than 2 seconds to set tracking to center.
Press the Tracking Up button and count number of
steps which the audio output is changed from Hi-Fi
(10KHz) to MONO (6KHz).
Press and hold the Tracking-Auto button on the remote
control more than 2 seconds to set tracking to center.
Press the Tracking Down button and count number of
steps which the audio output is changed from Hi-Fi
(10KHz) to MONO (6KHz).
If the difference are more than 3 steps, set the X Value
adjustment driver (JG153) to 

4

 of Fig. 2-2-B. Change

the X Value and adjust it so that the value becomes
within 2 steps.

1.

2.

3.

4.

5.

6.

7.

1

2

3

4

5

6

7

8

9

10

1. Tension Connect
2. Tension Arm
3. Guide Roller
4. Audio/Control Head
5. X value adjustment driver hole

6.

 7.

8.
9.

10.

P4 Post
T Brake Spring
T Reel
S Reel
Adjusting section for the Tension Arm position