Load
a bulk-erased
cartridge
in the
unit.
Connect
an
audio signal
generator to the
line
record input. Set the generator
for
1,000
Hz
at
a
level of
0.5V. Adjust the record level control
for
-10
VU
on
the
front
panel
meter.
Connect
an
oscilloscope to the output
and
begin recording. Observe
the oscilloscope
and
adjust
the
BIAS
LEVEL
Land R controls
for
the
peak
output with
no
distortion
of the 1,000
Hz
wave
form.
5-15.
VU
METER
CALIBRATION
While
recording the 1,000
Hz
tone,
adjust
the record level control
until
the external meter
indicates
the output level
set
in 5-7.
Now
adjust
the
METER
CAL
R
REC
and
L
REC
so
that
the
front
panel
VU
meter
indicates
0
VU.
5-16.
RECORD
EQUALIZATION
Set the signal generator
for
15
kHz
and
reduce
the
generator
output level
10
dB.
DO
NOT
ADJUST
THE
FRONT
PANEL
LEVEL
CONTROL.
While
recording the
15
kHz
tone,
adjust
the
REC
EQ
L
and
R
for
10
dB
below
the
output 1
eve
1
set
in 5-7.
5-17.
CUE
RECORD
ADJUSTMENTS
5-18.
BIAS
TRAP
TUNING
Referring to 5-12 connect
an
oscilloscope to
test
point Q
on
the
Record
Amplifier Board. Referring to Wiring Diagram,
activate
the external
cue
record control
by
connecting remote control terminal
21
to 20.
With
a
non-metallic screwdriver, tune
L3
for
minimum
100
Hz
signal as observed
on
the
oscilloscope.
5-19.
CUE
BIAS
LEVEL
Connect
an
audio signal generator to the external
cue
input
and
reconnect the oscilloscope to the
cue
playback output
(refer
to Wiring
Diagram).
Set the generator
for
1,000
Hz
at
a level
10
dB
below
there-
ference amplitude determined in Section 5-11.
Load
a bulk-erased
cartridge
in the
unit,
activate
the external
cue
record
control,
and
begin recording
the
1,000
Hz
tone
from
the signal generator. Observing the
oscilloscope,
adjust
the
BIAS
LEVEL
Q control
for
the
peak
output with
no
distortion
of
the
1,000
Hz
wave
form.
5-20.
CUE
TONE
GENERATOR
FREQUENCY
The
frequency of the 1
kHz,
optional
Q1
150
Hz,
and
optional
QII
8
kHz
cue
generators are adjusted
by
trimmers
R11,
R10,
and
R12
on
the
Record
Control
and
Tone
Generator Board. These
controls
are
set
at
the
factory
and
should not require subsequent adjustment.
5-21.
MECHANICAL
ADJUSTMENT
AND
MAINTENANCE
27
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