JVC KD-D30 - Page 9

KD-D30 A/B/C/E/J/U
is available at — 8 dBs at the LINE OUT
terminals.
2. After checking to see if the Peak level
indicator become O, record the signal
applied to both left and right channels
using normal tape.
3. Play back the recording part. Perform
the recording signal adjustment with
VR102 and VR202 so that the peak
level indicator become O.
Adjusti
Step Item Adjustment justing Standard Remarks
point value
3*
|
Checking
Record
1
kHz,
50
Hz
and
12.5
kHz
signals
|
For
SF/
Reference
This
checking
should
be
performed
for
record/
at
an
input
level
of
O
dB
to
—20
aB.
NORM
frequency;
normal
tape
and
for
both
right
and
left
playback Play back the tape. tape; 1 kHz channels.
frequency
Check
to
see
that
the
50
Hz
and
12.5
kHz
|
VR103
1.
Bias
current
adjustment
for
a
response
signal
output
deviations
fall
within
the
203
0+3
dB
cassette
deck
should
generally
be
standard range, using the 1 kHz signal out- at 50 Hz performed referring to the record/
put
as
a
reference.
For
Metal
playback
frequency
response.
This
is
tape; 0+4 dB because the frequency response of a
Increase in high frequencies :
(with a small bias current) VR104 at 12.5 kHz cassette deck depends more greatly
=
204
upon
the
bias
current
than
does
that
a Ny 2
3 MA \ of an open reel deck.
2 ON Gatimunnlevel 2. If the bias current is not properly ad-
Q
|
justed,
the
record
and
playback
3
Decrease
in
high
frequencies
characteristics
become
as
shown
ie (with a larger bias current) left
50Hz 1kHz 12.5kHz
Frequency (Hz)
4
Adjusting
1.
Apply
a
1
kHz,
approx.
—
10
dB
signal
|
VR102
Oo
VU
The
level
difference
between
left
and
recording
to
the
LINE
IN
terminals.
Adjust
the
202
right
channels
for
SF/NORM
tape
and
level
recording
level
controls
until
the
signal
metal
tape
should
be
less
than
1
dB.
Perform the adjustment using a normal
tape, level difference between recor-
ding and playback for metal tape,
should be less than 1.5 dB, and that
between left and right channels should
also be less than 1 dB.
5
Checking
1.
Record
a
1
kHz,
—8
dBs
signal
to
LINE
SF/NORM
Be
sure
to
perform
this
adjustment
record/
IN
terminals
and
perform
recording
with
tape;
Less
following
bias
current
and
recording
playback
the
peak
level
indicator
become
0.
than
2.5%
level
adjustments.
signal
2.
Play
back
the
recorded
part.
distortion
Check
the output
with
a distortion
SA/CrO2
meter to see if the value conforms to tape; Less
the standard value. than 3%
Metal tape;
Less than
2%
6 Checking 1. Record a 1 kHz, O GB signal. Stop the in- SF/NORM,
signal to put by disconnecting from the terminal and Metal
noise ratio to perform nonsignal recording. tapes;
in record- 2. Play back the recorded part. Measure More than
ing/play- the O dB recording output and the non- 42 dB
back signal recording output for comparison
using an electronic voltmeter.
Check to see if the value conforms to
the standard value.
7
Checking
3.
Apply
a
1
kHz
signal
to
the
LINE
IN
ter-
More
than
For
the
measuring,
connect
a
band
pass
erasing
minals.
Adjust
the
recording
level
con-
65
dB
filter
between
the
deck
and
the
elec-
coefficient
trols
until
the
peak
level
indicator
tronic
voltmeter.
become 0. Input Tape deck
2.
Perform
recording
with
the
signal
(1kHz
OdB
(recording
enhanced by 20 dB. | #20dB) erasing)
3. Erase a part of the recording.
4. Measure the output difference between Band pass [ Electronic
the
erased
part
and
nonerased
part
to
filter
voltmeter
compare with an electronic voltmeter. (1kHz)
= ee Hold less than 1 oe mm gap to the magnet from the hall IC.
= 9.2
No. 4209