JVC TD-W718BK - Mechanism Adjustment; Head Azimuth Adjustment; Tape Speed and Torque Checks

TD
-
W
717
TNC
/
J
TD
-
W
718
BKA
/
B
/
E
/
EN
/
G
/
U
/
UT
Mechanism
Adjstment
OdBs
=
0.775
V
Conditions
Item
Adjustment
and
Confirmation
Standad
value
Adjust
point
Adjusting
Head
azimuth
Test
tape
:
VTT
704
(
12.5
kHz
)
1
.
Connect
an
electronic
voltmeter
to
the
LINE
OUT
terminals
.
2
.
Play
back
the
VTT
704
(
12.5
kHz
)
test
tape
.
3
.
Adjust
the
head
angle
with
the
screw
(
FWD
and
REV
)
until
the
reading
of
the
electronic
voltmeter
becomes
maximum
for
both
channels
(
phase
difference
must
be
”
0
”
.
)
4
.
Repeat
the
adjustment
in
FWD
and
REV
modes
as
well
as
for
the
decks
A
and
B
.
5
.
Confirm
that
difference
level
between
deck
A
and
deck
B
within
2
dB
.
Maximum
Screws
(
FWD
,
REV
)
Deck
A
,
B
REV
Adi
F
W
ws
Deck
0
:
Normal
;
VR
701
High
;
VR
702
Deck
|
§
;
Normal
;
VR
703
High
;
VR
704
1
.
Connect
a
frequency
counter
to
the
LINEOUT
terminals
.
2
.
Perform
normal
speed
adjustment
first
,
and
then
do
high
speed
adjustment
.
3
.
Play
back
the
VTT
712
test
tape
.
4
.
Adjust
for
normal
speed
Adjust
VR
701
(
deck
[
A
]
)
and
VR
703
(
deck
[
B
]
)
for
normal
speed
at
3000
Hz
.
5
.
Adjust
for
high
speed
After
adjustment
of
normal
speed
,
adjust
VR
702
(
deck
[
Aj
)
and
VR
704
(
deck
\
B
}
)
for
high
speed
at
6000
Hz
.
6
.
Difference
in
FWD
and
REV
frequencies
must
be
less
than
48
Hz
.
Normal
speed
:
Deck
@
,
1
:
3000
±
15
Hz
High
speed
:
Deck
0
,
1
:
6000
±
30
Hz
1
.
After
adjustment
of
normal
speed
,
then
adjust
high
speed
.
2
.
For
high
speed
adjustment
,
set
the
deck
for
play
mode
,
and
shortcircuit
between
H
.
SPEED
TP
and
GND
.
3
.
Do
not
do
anything
while
H
.
SPEED
and
TP
GND
are
shortcircuited
.
Adjusting
Tape
speed
(
motor
speed
)
Test
tape
:
VTT
-
712
(
3
kHz
)
less
than
0.17
%
(
WRMS
)
Connect
a
wow
and
flutter
meter
to
LINE
OUT
terminals
.
Play
back
the
VTT
712
test
tape
.
Check
to
see
if
the
reading
of
the
meter
is
less
than
0.17
%
(
WRMS
)
.
Checking
wow
and
flutter
Test
tape
:
VTT
-
712
(
3
kHz
)
Employ
a
torque
testing
cassette
tape
(
TW
2111
[
FWD
]
/
TW
2121
[
REV
]
for
the
checking
,
or
remove
the
cassette
cover
and
use
a
torque
gauge
.
27
-
70
g
-
cm
Checking
play
back
torque
Torque
gauge
TW
2111
(
FWD
)
TW
2121
(
REV
)
Measure
the
torque
in
the
fast
forward
mode
in
the
same
manner
as
in
the
above
.
Test
cassette
:
TW
2231
(
FWD
)
,
TW
2241
(
REV
)
90
-
200
g
-
cm
Checking
fast
forward
/
rewind
torque
Torque
gauge
TW
2231
(
FWD
)
TW
2241
(
REV
)
(
No
.
4358
)
19