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In normal circumstances, the tape path system does not
need to be adjusted. However, after removing or replacing
one of the parts shown in Fig. 4-3-1, you should check and
adjust the tape path. The adjustment of the tape path is
carried out while monitoring the envelope waveform of the
video head output, using an oscilloscope. To make sure
that the tape drawn off the reel runs freely and without
excessive tension along all the tape guides and cylinders
(drums), it is also important to check each tape guide by
eye.

S reel

T reel

T guide roller

S guide roller

Audio R/P head assembly
(ACE head) Capstan shaft

Loading guide

T tape
guide

Pinch roller

Cylinder
(Drum)

Full erase
head

S tape
guide

BT post

0 tape guide

Fig. 4-3-1

1. Select a PAL or NTSC alignment tape or blank cassette

tape, according to the transmission system of the VCR
you are repairing.

NTSC: For models with 525 scanning lines and a field

frequency of 60Hz

PAL:

For models with 625 scanning lnes and a field
frequency of 50Hz

2. Clean the tape guides, the cylinder(drum), the capstan

Shaft, the audio R/P head (ACE head) and the full
erase head.

3. Using an oscilloscope, adjust the height of the guide

roller and carry out horizontal position adjustment,
height adjustment and azimuth adjustment on the audio
R/P head (ACE head). When observing the envelope
waveform, bring the CH-1 probe into contact with the
envelope waveform test point, and bring the CH-2 probe
into contact with the switching pulse (SW P) test point.
While adjusting the tape path, set the trigger at the low
side of the switching pulse (SW P) in order to observe
the output waveform on the CH-1 side of the video
head.

NOTE:The contact point for the oscilloscope varies from
one model to another, so to find the correct point for your
model, refer to the figure entitled “Test point for tape path
adjustment” in the electrical circuit section of the service
manual.
4. When checking the tape path by eye, use a dental

mirror.

1. Refer to sections 3-9-2, and remove the opener

mountIng .

2. Position the height adjustment tool (J-6090-055-A) 

3

under the full surface of the protrusion 

2

 on the load

lever assembly 

1

, as shown in Fig. 4-3-2.

3. Using your firlgers, gently screw the adjustment nut 

4

clockwise into the nut box (J-6082-045-A) 

5

 until the

protrusion 

2

 of the load lever assembly 

1

 touches the

height adjustment tool (J-6090-055-A) 

3

 and the screw

starts to feel tight. Next, loosen the adjustment nut 

4

by 270° anticlockwise.

4. Load a cassette tape (NTSC: T-160, PAL: E-240) and

switch to PLAY mode. Check that when you do this, no
scratches appear on the upper or lower edges of the
tape. If scratches do appear, re-adjust the height.

Arrange the equipment so that the whole surface of the 
projection on the load lever assembly is positioned over 
the height adjustment tool (J-6090-055-A) when seen from 
directly overhead.

5

 Nut box

     (J-6082-045-A)

3

 Height adjustment

     tool (J-6090-055-A)

1

 Load lever

     assembly

2

 Protrusion

4

 Adjustment nut

Fig. 4-3-2

1) Play the Alignment Tape (NTSC: MH-1, PAL: MH-2) and

check that the envelope waveform is at its maximum at
the tracking centre. Then, after loosening the S guide
roller and the T guide roller by rotating them
anticlockwise, tighten them in turn until the envelope
waveform becomes flat. If the envelope waveform is not
at its maximum at the tracking centre, refer to section 4-
3-4 and carry out a rough adjustment of the horizontal
position of the audio R/P head (ACE head) before
adjusting the guide rollers.

2) Adjust the S guide roller.

1

 Press the tracking button (Channel – ), and check

whether, when the envelope waveform has reached
50% of its maximum, the front half of the envelope
waveform is flat. If not, fine-tune the S guide roller as
follows.

a. If the front half of the envelope waveform is as shown

in Fig. 4-3-4 (a), this means that you have pressed the
S guide roller too far. Therefore, loosen it slightly, and
when it is in the state shown in Fig. 4-3-4 (b), tighten it
again, stopping when the envelope waveform is flat.

b. If the front half of the envelope waveform is as shown

in Fig. 4-3-4 (b), this means you have not pressed the
S guide roller far enough. Therefore, tighten it slightly,
stopping when the envelope waveform becomes flat.

c. If the front half of the envelope waveform is as shown

in Fig. 4-3-4 (c), it may happen that when you tighten
the S guide roller, the wrapper waveform does not
disappear, but sinks into the flat part, as shown in Fig.
4-3-4 (d). If this happens, the status shown in Fig. 4-3-
4 (c) is normal, so loosen the S guide roller, then
tighten it again until the envelope waveform is as
shown in Fig. 4-3-4 (c).

2

 Check that at the tracking centre, the output of the

front half of the envelope waveform is not less than
80% of the maximum.

3

 Rotate the S guide roller 20° anticlockwise.

3) AdjusttheTguide roller.

1

 press the tracking button (channel – ) and check

whether, when the envelope waveform is 50% of
maximum, the back half of the envelope waveform is
flat. If not, loosen the T guide roller slightly, then
tighten it gradually until the back half of the envelope
waveform becomes flat.

2

 Check that the output for the back half of the envelope

waveform is at its maximum at the tracking centre.

4) Check that the envelope waveform does not fluctuate

when you switch from F-SEARCH to PLAY or from R-
SEARCH to PLAY. If it does fluctuate, repeat steps 3)
and 4).

Normal

Pressed
too far

Not pressed
far enough

Eccentric screwdriver
(J-6082-044-A)

S guide roller

T guide roller

Do not touch
the fixed
screw

The tape should not pass along
the cylinder lead surface

Fig. 4-3-3

If the envelope waveform 
is at maximum at the 
tracking centre, adjust to 
flat.

In normal status, the waveform 
will be flat even when the 
envelope waveform is reduced 
to 50%.

100%

50%

50%

50%

50%

50%

(a) S guide roller
pressed too far

(d) S guide roller
pressed too far

(b) S guide roller not
pressed far enough

(c) Normal status for
wrapper waveform

Fig. 4-3-4

1) Play the alignment tape (NTSC: MH-1, PAL: MH-2) and

observe the waveform of the audio output, using an
oscilloscope.

2) Loosen the height adjustment screw in the counter-

clockwise direction and decrease the amplitude of the
audio output waveform. In this state, tighten the screw
in the clockwise direcion and maximize the amplitude.
Slightly tighten the screw further in the clockwise
direction and decrease the amplitude, and then loosen
it slowly in the counterclockwise direcion until the
amplitude starts to reach the maximum.

3) Set the amplitude of the audio output waveform to

maximum by rotating the azimuth adjustment screw.

4) Make sure that the tape edge is running between the

top of the audio head and the bottom of the control
head.

Gaps A and B should be roughly equal.

NOTE: Rotate the adjustment screw with a slotted screw-
driver. Do not apply excessive force vertically. As the
height adjustment screw also adjusts tilt, rotate it slowly.
Do not rotate it excessively. And apart from the this screw,
and height adjustment screw, the screws is precisely
adjusted before shipment from the factory, and should not
be tampered with. Tampering with these screws can lead
to scratching of the tape and other problems.

Azimuth adjustment screw

Audio R/P head assembly
(ACE Head)

Height adjustment
screw

This screws is precisely
adjusted and should not be
tampered with.

Tape

Control head

Audio head

A

B

A=B

Fig. 4-3-5

1) Play the alignment tape (NTSC: MH-1, PAL: MH-2).
2) Press the tracking buttons (channel + and channel – )

simultaneously and set the tracking to the centre.

3) Using an oscilloscope, observe the waveform of the

video head output.

4) Loosen the two fixed screws on the audio R/P head

(ACE head) by between 20° and 30° anticlockwise.

5) Using a slotted screwdriver, adjust the position of the

audio R/P head (ACE head). At the position where the
amplitude of the envelope waveform is at its maximum
at the tracking centre, tighten the fixed screw on the
audio R/P head (ACE head). When you do this, check
that the envelope waveform changes equally whether
the tracking is shifted by pressing the tracking button in
the plus or the minus direction.

6) Play the alignment tape (NTSC: MH-1 PAL: MH-2) and

check that the amplitude of the envelope waveform is at
its maximum at the tracking centre. If not, repeat steps
1) to 6).

7) Refer to the electrical adjustments section of the service

manual, and adjust the switching position of the servo
circuit.

1. When you press the tracking buttons (channel+ and
channel – ) simultaneously, the tracking is reset to the
tracking centre. When the tracking is at the tracking
centre, the message “T - : - “ will appear in place of the
clock display on the front panel. If you keep pressing the
channel– button the messages “T- : “ and “T - - : “ will
appear, while if you keep pressing the channel + button,
the messages “T : - ” and “T : - - “ will appear. Three
seconds after you stop pressing the tracking buttons, the
clock displav will re-appear.
2. The check described in paragraph 6) is not necessary
for models in which the only tape speed is SP mode.

Audio R/P head assembly

Scew

Screw

Slotted
screwdriver

After resetting the tracking to the
tracking centre, set the envelope
waveform to maximum.

Fig. 4-3-6

Fig. 4-3-7

1) Play the alignment tape (NTSC:MH-1, PAL:MH-2) and

check that the envelope waveform is activated immedi-
ately and that there are no fluctuations in the envelope
waveform or the audio output waveform.

2) Load a cassette tape (NTSC:T-120, PAL: E-180) and

use it to record and replay. Check that the envelope
waveform is activated immediately and that there are
no fluctuations in the envelope waveform or the audio
output waveform. (When recording on the tape, input
1kHz to the audio input terminal. Use a scratch-free
cassette tape (NTSC: T-120, PAL: E-180).) Check that
at the tracking centre, the front half down and back half
down are not more than 20% of the value at the point
where the envelope waveform amplitude is at its
maximum.

3) Check that the envelope waveform is activated immedi-

ately when you switch from PLAY to R-SEARCH or
from R-SEARCH to PLAY. Check that there is no slack
in the tape next to the pinch roller.

4) Check that the envelope waveform is activated immedi-

ately when you switch to PLAY from FF, REW, F-
SEARCH, R-SEARCH or STOP mode. Check that there
is no slack in the tape next to the pinch roller.

5) Check that the tape is not curling or riding up on the

upper or lower flanges of the tape guides in PLAY, FF,
REW, F-SEARCH or R-SEARCH modes.

6) Check that in PLAY mode. the tape runs as shown in

Fig. 4-3-7.

7) Load a tape (NTSC:T-160, PAL: E-240) and play it

back. carry out the checks described in steps 3) to 5)
above.

No. 0 tape
guide

S tape guide

S guide
roller

Cylinder
(drum)

T guide roller

Audio R/P head assembly
(ACE head)

T tape guide

Loading guide
post

BT post

Full erase
head

Pinch roller

Capstan shaft