Teac A-4010GSL - Overall Frequency Response (Record)

OVERALL FREQUENCY RESPONSE
IMPORTANT:
To
avoid
saturation
of
the
tape,
these
checks
should
be
made
at
least
20
dB
below
the
specified
input
level.
Any
signal
feeding
into
the
test
equipment
should
be
filtered
out
by
adjusting
the
external
bias
trap.
A
broad
band
VIVM
may
be
used
on
the
output
of
the
unit
for
this
adjustment.
BIAS
switch
in
HIGH
position
7
9.
10.
Thread
a
record
test
tape
Scotch
#203
on
the
unit,
the
BIAS
switch
must
be
at
HIGH
position.
7
Apply
a
signal
swept
from
50
Hz
to
15
kHz/-28
dB
to
the
unit
while
recording
on
a
record
test
tape.
11.
"Repeat
the
above
procedure
for
3-3/4ips
using
a
signal
from
50
Hz
12.
to 7.5 kHz.
NOTE:
If
the
response
is
not
uniform,
the
heads
should
be
checked
for
accumulated
oxide
and
dirt.
Then
if
no
dirt
is
found,
the
equalization
coils
L-102/202
should
be
adjusted.
If
further
adjustment
is
required,
C-117/217
must
be
changed,
if
the
high-end
response
is
too
high,
a
lower
value
capacitor
must
be
installed.
BIAS
switch
in
NORMAL
position
NOTE:
This
is
a
performance
check
only,
no
adjustment
is
provided
and
HIGH(Scotch
#203)
adjustment
should
be
completed
before
start~
ing
this
procedure.
Thread
a
Scotch
#150
high
output
tape
on
the
unit.
Place
the
BIAS,
EQ/LEVEL
switch
in
the
NORMAL
position.
Repeat
the
overall
response
check
at
both
tape
speeds.
The
record
equalization
should
give
the
proper
frequency
response.
After
this
check,
return
BIAS,
EQ/LEVEL
switch
to
HIGH
position.
RESPONSE IN dB
M~-O301
Fig.
6-12
Freq.
Response
Limits
~Record-