Teac A-3340 - BIAS SWITCH MODE PROCEDURES; NORMAL POSITION OPERATION; HIGH POSITION OPERATION

-BIAS switch in NORMAL position-
Thread
the
unit
with
a
record
test
tape
(Scotch
150).
Set
tape
speed
selector
to
H
(l5ips).
Adjust
the
AF
oscillator
to
obtain
an
output
level
of
-23
dB
at
OUTPUT
jacks.
Apply
a
signal
swept
from
50
Hz
to
18
kHz
to
the
unit
while
recording
on
the
test
tape.
With
MONITOR
switch
at
TAPE
po-
sition
monitor
the
output
at
the
VIVM.
See
figure
8-7
for
proper
response
limits.
Repeat
the
above
procedures
for
L
(7-1/2ips),
using
a
signal
swept
from
50
Hz
to
15
kHz.
NOTE
If
response
is
not
uniform
the
heads
should
be
checked
for
accumulated
dirt
or
tape
oxide.
If
heads
are
clean
the
equalization
coils
L
301
and
L
303
should
be
adjusted
(both
speed).
-BIAS switch in HIGH position-
a
2
Thread
the
unit
with
a
record
test
tape
(Scotch
203).
Repeat
the
overall
response
check
at
both
tape
speeds.
The
record
equalization
should
give
the
proper
frequency
response.
RESPONSE IN dB
50 100 500 K
FREQUENCY IN Hz. ereeet
Fig.
8-7
Frequency
Response
Limits