4-2-5. TILT & AZIMUTH ADJUSTMENT OF
THE A/C HEAD
<<NOTE>>
This procedure
should
be
performed only when the A/C Head is
replaced
or
posts heights are readjusted.
<<TOOL>>
Alignment Tape ; VFM8180HADH
Check Light ;
VFK0343
Screwdriver(+) ; Purchase locally
VHS
Video Tape
1.
Play
back a
VHS
Video tape which the amount of tape
winding of a Supply
Reel
is
more than the amount of
tape winding of a Take up
Reel.
Turn
a screw
(B)
to
clockwise until Waving or
Frilling appears
in
the
lower
edge of
P4
post
as
Figure M
11.
A/C
Head Base Unit
Figure
M14
<<NOTE>>
There is easy method to
check
Waving
or
Frilling.
If
there is
Waving
or
Frilling in the lower edge,
White
Black pattern which
is reflected on the tape will curve
or
not
linear. (Figure M12)
2.
Turn
the screw
(B)
to counter-clockwise until waving or
frilling do not appear
in
the
lower edge of
P4
post.
3.
Connect the scope
CH1
to the Normal Audio Output
CH1
and
the
scope
CH2
to
the
Normal Audio Output
CH2
on
the
rear
panel.
4.
Play
back the 2-nd portion (Normal Audio
1OKHz)
of
the
alignment tape
(VFM8080HQFP).
5.
Adjust the screw
(C)
so that these phases of both chan-
nels
match
as
shown
in
Figure
M15.
CH1!\ANV
I
I
CH2!\NVV
Figure
M15
4-7
6.
Adjust the screw
(C)
and
(B)
so that
CH1
and
CH2
output levels become maximum, these phases of both
channels much
at
the same time (Figure
M16).
During
this adjustment the Lock screw
(D)
does not touch the
NC
Head
Base
as
shown
in
Figure
M17.
space
CH1
I
CH2
{\
A (\ (\ r
I:::um
I V:V V
V_
t
Figure
M16
Lock Screw
(D)
----Screw
(C)
AIC
Head Base
Figure
M17
7.
Turn
the screw
(C)
to clockwise so that the difference of
phases of both channels become
180
degrees
as
shown
in
Figure M
18.
CH1
CH2
Figure
M18
9.
Tighten
the
Lock screw
(D)
so that these phases of both
channels match
as
shown
in
Figure M
15.
1-
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w
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