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5.
Tune
to
9O0MHz
and
adjust
Generator
so
that
curve
appears
on
Oscilloscope.
6.
Check
L2,
L3,
L4
again;
if
necessary,
distribute
any
error
between
both
frequencies.
Note:
105MHz
curve
is
typically
slightly
higher
than
90MHz.
D.
IF
ADJUSTMENTS
1.
Tune
to
approximately
98MHz
(must
be
an
unoccupied
frequency),
and
adjust
FM
Generator
to
display
curve
on
the
oscilloscope.
2.
Adjust
I-1
and
I-101
for
maximum
and
symmetrical
curve
using
as
little
RF
input
signal
as
possible.
3.
Remove
detector
probe.
E.
DETECTOR
ADJUSTMENT
1.
Remove
Detector
Probe,
and
connect
Tape
Output
to
Distortion
Analyzer
and
Oscilloscope.
2.
Connect
DMM
between
P-703
(-)
and
P-704
(+).
3.
Tune
to
98MHz
and
feed
1000uV
from
FM
Generator
(Modulate
1kHz
100%,
Mono).
4.
Adjust
I-102
Secondary
(front)
for
lowest
THD.
Specification:
less
than
0.1%
5.
Adjust
L-102
Primary
(rear)
for
OV + 50mV
reading
on
DMM.
6.
Repeat
until
no
further
improvement.
F.
STEREO
DISTORTION
& SEPARATION
1.
Tune
to
98MHz
and
feed
1000uV
from
FM
Generator.
Modulate
1kHz,
100%
left
(or
right)
only.
2.
Adjust
I-1
and
I-101
just
slightly
so
that
distortion
on
left
(or
right)
channel
becomes
minimun.
3.
Check
stereo
distortion,
wide
IF;
Specification:
less
than
0.1%
,
L
+R,
L only,
R only,
L -
R.
4.
Next,
select
IF
NARROW,
and
check
distortion;
Specification:
less
than
2%,
L
only,
R
only,
L
-
R.
5.
Set
IF
to
wide
and
modulate
L only.
Adjust
R-176
for
minimum
output
on
right
channel.
Next,
modulate
R only
and
adjust
R-176
for
minimum
output
on
left
channel.
If
necessary,
readjust
R-176
so
that
readings
become
same
on
both
channels.
Specification:
less
than
-45dB.
6.
Select
IF
NARROW,
and
modulate
left
(or
right)
channel
only.
Adjust
R-177
for
minimum
output
on
right
(or
left)
channel
VTVM
and
oscilloscope.
If
necessary,
readjust
R-177
so
that
readings
become
same
on
both
channels.
Specification:
less
than
-40dB.
G.
AUTO
SEARCH
LEVEL
1.
Set
IF
to
wide.
Connect
DMM
between
P-935
and
Ground.
2.
Set
FM
Generator
output
to
10uV
and
adjust
R-144
so
that
reading
just
goes
from
0 V to
4.4V.
Tolerance:
+ 2uV.
10
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