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37

1) After releasing the auto tracking, lightly turn the fixing

screw. Turn the (+) type driver (Ø 3 ~ Ø 4) on the X-dis-
tance adjusting hole to the right or left. Adjust the RF
envelope level to the maximum point and then fix the fix-
ing screws.

2) For the 31mm head, adjust it with the SP tape recorded

in the width of 31mm since the head travels on the tape
track only for SP with the width of 58mm.

1) Check the tape pass status between the pinch roller and

the take-up guide.(Check there is crumpling of the tape
pass and folding of the take-up guide.)

1) 

(1) When holding of the take-up guide bottom occurs 

Turn the tilt adjusting screw (C) clockwise and travel it
stably to ensure there is no crumbling or folding of the
tape. 

1) 

(2) When holding of the take-up guide top occurs

Turn the tilt adjusting screw (C) anti-clockwise and

travel it stably to ensure there is no crumbling or fold-
ing of the tape. 

1) 

2) Check there is folding of the tape at the bottom or top

of the take-up guide in cutting-off the REV mode 

If the RF waveform is changed after adjusting the A/C head,
perform fine adjustment to ensure the RF waveform is flat-
tened.

1) Connect the probe of Oscilloscope to the audio output

jack.

2) Ensure that Audio 1KHz, 7KHz output is flattened at the

maximization point by adjusting the Azimuth adjusting
screw (A).

• Oscilloscope
• Standard test tape

(only for SP)

• Driver (+) Type Ø 4

• Audio Output Jack

• Play the standard test 
• Tape, 1KHz, 7KHz.

• Azimuth Adjusting

Screw (A) 

• Height Adjusting Screw

(B)

• Oscilloscope
• Standard test tape

(only for SP)

• Driver (+) Type Ø 4

• CH-1: PB RF Envelope
• CH-2: NTSC ; SW 30Hz

PAL:SW 25Hz

• Head switching output

point

• RF Envelope output

point

• Play the standard test

tape.

38

1) Play the blank tape (empty tape) and check whether the

guide roller crumbles or wrinkles the tape and adjust it if
necessary. 

2) Check that the RF envelope output waveform is flat, and

adjust the height of the guide roller while playing the
standard test tape.

3) Adjust the switching point. 
4) Check the RF envelope output is   the maximum when

the tracking control locates at the center. If not maxi-
mum, set up to ensure that RF envelope output
becomes the maximum by turning the (+) type driver (Ø
3 ~ Ø 4) on the base A/C groove.

• Oscilloscope
• Standard test tape 

(only for SP)

• Post Height Adjusting

Driver 

• Driver (+) Type Ø 5

• CH-1: PB RF Envelope
• CH-2: NTSC : SW 30Hz

PAL:SW 25Hz

• Head switching output

point

• RF Envelope output

point

• Play the blank tape. 
• Play the standard test 

tape.

• Fine adjustment of

guide roller 

• Switching Point 
• Tracking Preset
• X-distance

1) Check that locking time of the RF and Audio waveform is

fallen within the measuring standard in conversion of the
play mode from the CUE or the REV mode. 

2) Readjust the paragraph 5 and 6 if it deviates from the

standard. 

• Oscilloscope
• 6H 3KHz Color Bar

Standard Test tape 

• Stop Watch

• RF Locking Time: Within

5 seconds

• Audio Locking Time :

Within 10 seconds

• CH-1: PB RF Envelope
• CH-2: Audio output
• RF Envelope output

point 

• Audio output jack

• Play the 6H 3KHz 

Color Bar Standard
Test tape.

1) Check there is no abnormality of every traveling post

status. 

2) There must be no abnormal operation of the counter in

occurrence of folding of the bottom tape. There must be
not abnormality of audio signal in damage of the top tape.

3) If there is abnormality, readjust the adjustment para-

graph 4 and 5.

• T-160 Tape
• T-120 Tape

• There must be no jam or curl at the

first, middle and end position of tape.

• Travel the tape at the position

of its first and end.

39

Color beat

Pollution of Full-Erase Head

o

S/N, Color Faded

Pollution of Video Head

o

Horizontal, Vertical Jitte

o

If operation of the position with (O) mark is abnormal even
after removing cause, replace it with substitute product since
it shows damage or wearing.

F/E Head

Video Head

A/C Head

Pinch Roller

Belt Capston

Clutch

Assembly A37

Pollution of Video Head or
Tape Transport System

Poor Sound, Low Sound

o

Pollution of Audio/Control
Head

o

Pollution of Pinch Roller or
Belt Capstan Belt

No tape wound or tape
wound loosely.
FF or REW impossible,
or slow turning

Deterioration of Clutch
Assembly D37 Torque

Pollution of Drum and
Traveling Device

Tape loosely wound in
REV or Unloading

o

Fig. C-9-3

Following abnormal phenomena may be repaired by
removal of foreign materials and oil supply. Check oiling is
required at the checking set or cleaning status is complete. 
Determine that necessity of checking and repair the set
exists after checking the using period of the set together
with the user. In this case, followings must be checked:

40

Recording density of the video is far higher than the audio.
Therefore video parts are very precise so as to allow only
error of 1/1000mm or so in order to maintain compatibility
with other videos. 
If one of these parts is polluted or old, same phenomena will
appear as they are damaged.
To maintain clear screen, regular check, replacement of old
and damaged parts and oil supply, etc are essential. 

Check and repair schedule is not constant since they vary
depending on method that the consumer uses video and
environment where the video is installed at. 
However, for the video used by common household, good
screen will be maintained if regular check and repair per
1,000 hour is performed. The following chart shows relation-
ship between using time and checking time:

(1) Grease: Floil G-3114 (KANTO) or equivalent grease

(Green)

(2) Grease: Kanto G-754, PL-433 (Yellow)
(3) Alcohol (Isopropyl Alcohol)
(4) Cleaning Patch (cloth)

(1) Removal of foreign material from video head (Fig. C-9-4)

Firstly try to use a cleaning tape.

(1) 

Use a cleaning patch if foreign materials are not removed
with the cleaning tape due to severe dirty of the head. 
Soak the cleaning patch in alcohol and put it to the head
tip. Smoothly turn the drum (turning cylinder) to the right
or left (In this case, the cleaning patch must not be
moved vertically).

(1) 

After completely drying the head, test the traveling status

of the tape.

(1) 

If alcohol (Isopropyl Alcohol) remains at the video head,
the tape may be damaged when this solution touches
with the head surface.

Never use a cloth bar (commercial sale)

(2) Wipe the tape transport system and the drive system

with the cleaning patch soaked in alcohol (Isopropyl
Alcohol) when removing foreign materials from them. 
1) The part touched with the traveling tape is called as

tape transport system. The drive system consists of
parts to travel the tape.

(2) 

2) Care must be exercised so that unreasonable force
to change the pattern will be applied to the tape trans-
port system during removal of foreign materials.