Teac A-3340 - RECORDING PERFORMANCE DETAILS; BIAS TRAP ADJUSTMENT

RECORD
PERFORMANCE
; IMPORTANT
Before
making
any
adjustments
on
the
record
amplifier,
be
sure
that
all
tests
in
the
HEAD
ALIGNMENT,
PLAYBACK
and
MONITOR
PER-
FORMANCE
sections
have
been
accomplished
and
that
all
adjust-
ments
are
correct.
Optimum
recording
performance
(Bias
levels,
recording
levels
and
frequency
response)
is
dependent
upon
tape
characteristics.
The
TEAC
A-3300
is
factory
set
for
Scotch
type
150
tape.
Service
data
is
based
upon
the
use
of
Scotch
150
or
equivalent
tape.
NOTE
The
bias
trap
tank
circuit
keeps
the
bias
signal
from
reaching
the
record
and
monitor
amplifier
and
under
normal
no
signal
conditions,
voltage
should
not
be
present
at
the
OUTPUT
jacks.
Qi07/108
x
ERASE
Q302/305
HEAD
8.5V Q301/304
BIAS TRAP
CHECK POINT L301/303
Fig. 7-6 Simplified Diagram -Record-
BIAS TRAP ADJUSTMENT
1. Place the RECORD BIAS switch to
HIGH and place the unit in RECORD
with no signal applied.
2. Connect a VIVM to the junction of
C 309/L 302.
3. Adjust L 302 for a minimum reading.
4. Connect the VIVM to the junction of
C 318/L 304.
5. Adjust L 304 for a minimum reading.
e
Fig. 7-7 Bias Leakage