Dokorder 7700 - Page 18

t}
2-3
PLAYBACK
FREOUENCY
RESPONSE
(19
cm/s &
9.5 cm/s)
a. Specification
-10
dB
1',t.0
dB
(15
KHz, 19 cm/s),
-10
dB l? Oe
(SO
Hz, 19 cm/s)
-10
dB
11.0
dB
(7.5
KHz, 9.5
cm/s),
-1
0 dB
t3
dB
(50
Hz, 9.5 cm/s)
b.
Adjustment
(1)
Adjust
the semi-f ixed resistors
VR-105
and VR-205
(19
cm/s).
(2)
Adjust
the semi-fixed resistors
VR
104
and VR-204
(9.5
cm/s).
c. Reference
Refer to
Fig.6-1.
d. Test tape, special
tools and
instruments required
DTT-S106
(700
Hz
-10
dB),
DTT-5113
(15
KHz
-10
dB), DTT-5102
(50
Hz
-10
dB), DTT-3106
(500
Hz
-10
dB), DTT
3110
(7.5
KHz
-10
dB),
DTT 3102
(5O
Hz
-10
dB)
or
equivalents,
and
VTVM.
e.
Test
point
Connect the VTVM to
the
line output
jacks.
f
. Mode of switch
(1
)
Tape
speed
SW-19
cm/s,
Monitor
SW-TAPE.
(2)
P.B.
level controls-MAX,
Record Ievel
controls-MlN.
g.
Procedure
(1)
After tlre above connection
is completed,
load
the
test tape
(DTT-S113)
on
the deck and
push
the
play
button to
enter
the
playback
mode.
(2)
Adjust
the semi-fixed
resistors VR 105
and
VR-205 on
the
AMP
PC
Board
(PCM-446),
so that the
line
gutput
levels
may
be
-10
dB
11.0
dB in reference
to the
level
(700
Hz
-10
dB).
(3)
When
the step
(2)
is completed,
play
the test tape
(DTT-5102)
and check the output
level is within
the
range of
-10
dB
+3
dB
-5
dB in reference to
the
level
(700
Hz
-10
dB).
(4)
Change
the tape speed
switch to the 9.5 cm/s
position,
then
play
the test tape
(DTT-3110)
and
adjust the
semi-fixed resistors
VR-104 and
VR-204
on the
AMP PC
Board, so
that the
line
output
levels may be
-10
dB
11.0
dB
in
reference
to the level
(500
Hz
-10
dB).
(5)
When the step
(4)
is completed,
play
the test
tape
(DTT-3102)
and check the output
level is within the
range of
-10
dB
t3dB
in
reference
to the
level
(500
Hz-1 0 dB).
2.4 SOURCE MONITOR LEVEL
a. Specification
0
dB
i0.5
dB of
the
line output
iacks.
-
b. Adiustment
3
Adjust the semi-fixed
resistors VR-103
and VR-203.
c. Reference
Refer to
F
ig. 6-1.
cl. Test tape, special tools and
instruments
required
Signal
generator
and
VTVM.
e. Test
point
Connect the VTVM to the
line output
jacks.
f
.
Mode of switch
(1f
Monitor
SW SOURCE
(button
in).
(2)
P.B.
level controls MAX,
Record
level
controls
MAX.
g.
Procedure
(l
)
Connect
the signal
generator
to the
line
input
iacks,
and apply
a 700 Hz signal of
-20
dB
to the line
r n
puts.
(2)
After
the
above connection
is completed, adjust
the
semi-fixed
resistors VR 103 and VR-203 on the
AMP
PC
Board
(PCM-446),
so that
the
line
output level
may
be
0 dB
10.5
dB on the
VTVM.
ry
t(
3
15