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2-21

1

(1) Rotate the loading motor manually to set to the loading-end

position.

(2) Check that the tip of the tension arm comes to the hole “A”

on the main deck.

(3) If the tip of the tension arm does not come to the above

step (2), loosen the screw 

6

 slightly and rotate the adjust-

ment pin.

2

(1) Play back the cassette torque meter, and check that the

torque value at the supply (left) side is  4.41 

± 0.39 x 10

-3

N·m  (indication value: 45 

± 4 gf·cm).

(2) If the indication is not of the above value, perform adjust-

ments in the following manner:
1) Remove the cassette torque meter.
2) Loosen the screw 

6

 slightly and rotate the adjustment

pin.

(Turn the adjustment pin clockwise to increase the torque,

and counterclockwise to decrease it.)

3) Check the above step (1) again, and repeat the adjust-

ments until the specified value is obtained.

4) Perform the tape transport system check.

Adjust pin

Tension arm 
assembly

2.5 mm dia. pole

6

“A”

Tip of the 
tension arm

Tension arm

4

6

7

8

9

14

11

2

13

1

SP pole 1

Tension 
 pole

Full erase 
head

Inertia roller

SP slant pole

Drum

TU slant pole

A/C 
head

Capstan

Pinch roller

Cassette tape

3

5 10 12

15

The tape transport parts are No.    ,    ,    ,    , and     .

+0

 –2.94

(1) Play back the cassette torque meter, and check that the

torque value at the take-up (right) side is
7.35

      

   x 10

-3

 N·m

(indication value: 75 

     

 g·cm).

(2) If not meet the specification, replace the clutch unit (T) and

confirm this section again.

1

(1) Play back the thin-type tape (E-240).
(2) Change the playback mode in the following order:
        PLAY  

→  SEARCH REV  →  SEARCH FWD  →  PLAY

(3) Check that creasing or damage to the tape does not occur at

the SP/TU guide rollers (pole base assembly), guide rollers
(S, T) or at the guide arm assembly.

+0

 –30

2-22

(2) Guide arm assembly

(a) If creasing of the tape or other tape damage occurs at

the flange on the guide arm assembly, adjust as follows:

(b) Eject the tape.
(c) Rotate the set screw 

9

 clockwise to raise the height of

the guide arm assembly. (Refer to Fig. 2-5-10)

(d) Play back the tape, and repeat this procedure until the

tape creasing or tape damage does not occur. If tape is
twisted between the capstan and the guide arm assem-
bly, fine adjust the height of the guide arm assembly.

(3) When adjusting the tape transport parts, be sure to perform

the interchangeability adjustment again.   (Refer to Section
2.5.1, 2.5.2 and 2.5.3.)

Upper flange setting height (42.33)

Guide Arm Assembly

Upper limit

Bottom flange setting height (29.68)

Guide Roller (T)

TU Guide Roller  

Upper limit

A/C head   

No restriction

Cutting surface of main deck 

(bottom reference surface)

Cutting surface of main deck 

(bottom reference surface)

Center of tape

36

5

4

Full-Erase Head

No restriction

SP Guide Roller

Bottom flange setting height (29.68)

Capstan

No restriction

3

36

2

Center of tape

Guide Roller (S)

SP Pole 1

No restriction Perpendicular

Tension Pole

No restriction

1

10

11

12

13

15

Bottom limit

Bottom limit

Upper limit

Set screw 

Guide arm assembly

Guide roller (S)

Guide roller (T)

9

7

8

2

(1) Guide roller (S), (T)

(a) If creasing of the tape or other tape damage occurs at

the guide roller (S) or (T), rotate the screws 

7

 and 

8

 in

the tightening direction to lower the height of the guide
roller (S)/(T).  At this time, be sure not to rotate the screw
for more than 1/2 turn.

To set the reference height of the guide rollers, tighten
the screw once until it reaches the end , then rotate it by
the following value in the releasing direction.
• Guide roller (S): 2.5 turns
• Guide roller (T): 1.5 turns

3-1

(1) Before performing an electrical adjustment, make sure that

the target point for the adjustment really is deviated and
actually requires adjustment.

(2) Ensure that the mechanism interchangeability adjustments have

been completed before proceeding to electrical adjustments.

(3) Before proceeding to electrical adjustments, leave the unit

ON for more than 5 minutes after turning the power ON.

(4) Use a 10:1 probe with the oscilloscope unless otherwise

specified.

Video signal generator
[TG-7/2(Shibasoku),Model 1411
(Tektronix), Model 430 P (Leader),
or equivalent]

Oscilloscope

Color monitor TV

Multimeter

Previously calibrated instrument.

Calibrated instrument with a 100
MHz or higher band measurement
capability.

Instrument with a 75

 ( video input.)

Calibrated instrument with a 10 M
or higher input impedance.

(1) Y/C color bars signal

(3) Composite pulse & bar signal

(1) Press the [STOP], [PAUSE] and [MENU] buttons simultan-

eously

.

(2) Press the [SHIFT  ] or [SHIFT  ] button to select “SERVO

ADJUST”,then press the [SET – ] or [SET + ] button.

(3) The front panel FDP shows the following information.

(4) Press the [SHIFT  ] or [SHIFT  ] button to switch the mode.
(5) Press the [V.LOCK – ] or [V.LOCK + ] button to vary the

adjustment value.

(6) Press the [MENU] button to cancel the SERVICE MENU.
(7) When the [RESET/CANCEL], [SET – ] and [SET + ] but-

tons are pressed simultaneously in step (3), all of the adjus-
tment values in the EVR ADJUST MODE will be reset.

(1) Press the [STOP], [PAUSE] and [MENU] buttons simultan-

eously

.

(2) Press the [SHIFT  ] or [SHIFT  ] button to select “EVR

ADJUST”,then press the [SET – ] or [SET + ] button.

(3) The front panel FDP shows the following information.

(4) Press the [SHIFT  ] or [SHIFT  ] button to switch the mode.
(5) Press the [V.LOCK – ] or [V.LOCK + ] button to vary the

adjustment value.

(6) Press the [MENU] button to cancel the SERVICE MENU.

A
Vp-p

B
Vp-p

C

2T

2T

A = 0.7, B = 0.3, C = 20T

Mode

Adjustment value

Mode

Adjustment value

Alignment tape

VFK1741 / VFK1743

(2) Composite color-bar signal (100% white, 75% chroma )

0.3 Vp-p

0.35 Vp-p

0.3 Vp-p

[Y]

(4) Y/C video sweep signal (B/W)

Y

C

0.7 
Vp-p

0.3 
Vp-p

0.3 
Vp-p

Color level: 75%

0.7 Vp-p

0.3 Vp-p

3-2

1

If the video adjustments are not completed before proceeding to the servo adjustments, reset the EVR ADJUST MODE adjust-
ment values as described in section 3.3.2 (7).

2

Before performing the servo adjustments, recording should be done in 48H mode for two minutes. (The TL tape feed amount is
automatically adjusted.)

Measuring

Measuring point (

* )

No.

Item

instruments &

Mode

Adjustment parts (

- )

Adjustment procedure

Input signals

Adjustment level (

+ )

(1) Set SERVO ADJUST mode “t6” as described

in the SERVO ADJUST MODE setting method.

(2) Set the oscilloscope as shown below.

1

SW point
adjustment

Oscilloscope
(Trigger: D-FF),
Alignment tape,
VFK1741

SERVO
ADJUST t6
3H PB

* VIDEO OUT terminal,

75

Ω terminated

- [V.LOCK–/+] buttons
+ 6.5 H ± 0.5H

(3) Play the alignment tape, check FM wave form

(TP5[P/R]: 8F) and optimize tracking.

(4) Adjust the [V.LOCK–] or [V.LOCK +] button so

that the duration from the trigger point to
V.SYNC start point is 6.5H.

2

V-LOCK
adjustment

Monitor TV,
Color bar signal

SERVO
ADJUST t3

3H REC

↓

3H PB
(PAUSE)

* VIDEO OUT terminal,

75

Ω terminated

- [V.LOCK–/+] buttons
+ Minimize vertical

dancing of image

(1) Insert a S-VHS cassette tape.
(2) Apply the color bar signal input.
(3) Set SERVO ADJUST mode "t3" as described

in the SERVO ADJUST MODE setting method.

(4) Set to 3H mode with the [SET+] or [SET–]

button, and perform recording and playback.

(5) Press the [PAUSE] button and adjust the

[V.LOCK –] or [V.LOCK +] button to minimize
the vertical dancing.

L12H REC

↓

L12H PB

(6) Perform recording and playback in L12H

mode.

(7) Adjust the [V.LOCK–] or [V.LOCK +] button to

minimize the vertical dancing.

3

Slow tracking
preset
adjustment

Monitor TV,
Color bar signal

SERVO
ADJUST t2

3H REC

↓

24H PB

* VIDEO OUT terminal,

75

Ω terminated

- [V.LOCK–/+] buttons
+ Minimize noise.

(1) Apply the color bar signal input.
(2) Set SERVO ADJUST mode "t2" as described

in the SERVO ADJUST MODE setting method.

(3) Perform recording in 3H mode and playback

in 24H mode.

(4) Adjust the [V.LOCK –] or [V.LOCK +] button to

minimize noise at the top and bottom of the
monitor screen.

V.SYNC start point

Trigger point

Oscilloscope setting

TRIG

SLOPE

SWEEP TIME/DIV range

TP4 [P/R]:7F

–

50 

µs/DIV

L24H REC

↓

L24H PB

(8) Perform recording and playback in L24H

mode.

(9) Adjust the [V.LOCK–] or [V.LOCK +] button to

minimize the vertical dancing.