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(h)
(i)
5.
ALIGNMENTS
Complete
the
alignments
in
the
following
orders:
1. FM
IF
alignment
2. AM
IF
alignment
3. FM
tracking
aligrrment
4. AM
tracking
alignment
5. FM MPX
decoder
circuit
alignment
5-1.
FM IF
ALIGNMENT
(a)
Connect
a
capacitor
0.01p
F
between
TPf
and
ground
before
the
alignmnet.
(b)
Connect
a resistor
220k
Q"in
series
with
the vertical input
terminals
of
the
oscilloscope
(Fig.
2).
(c)
Remove
the
capacitor
(4.7 UF
) from
the
terminal
@
before the
alignment(Fig.
2).
(d)
Turn the
selector
switch
to
FM
MONO.
(e)
Turn the tuning
knob
to
the
right
and
set
dial at high end
of
scale.
(f
)
Connect
the output
leads
of
sweep
generator
to
the FM
antenna
terminals.
(Fig.
2
).
(g)
Connect the vertical
input of
oscilloscope
to
the FM
meter output terminal
@
,
when
connecting
to the FM
meter
terminal,
disconnect
the
meter
lead, then
terminate
4.7k
Q
between
the
terminal
@ and
ground.
Set the output
level
of
sweep
generator
to
60
dB.
Adjust the FM
IFT
cores
(T+, Tb,
TO)
as shown
in
Fig.
Z.
Note:
When
it
is
difficult
to
get
synchronism
of
oscilloscope,
make
eonnection
between
the
oscilloscope
and
sweep
generator
for
easy
synchronism
refer-
ing
to
the
operating
instructions.
8
(j
)
Set the output
level
of
sweep
generator
to
100 dB, then keep the top
of
the
pattern
flat
and
check
the
tuning
eenter
frequency
does
not
move when feed
the
high level
input
(100 dB)
to
FM
antenna
terminal,
if it is
moved, repeat
the
steps
( tr ) to ( i
).
(k)
Disconnect
the
vertical
input
of
oscillo-
scope
from
the FM
meter
output
terminal,
then
eonnect
the
vertical
input
leads
of
oscilloscope
to TPt
(
FIg.
4).
(l)
Adjust the
S-curve
pattern
for
adjusting
the
cores
of
the
FM
IFT
T7.
(Linearity
is
improved
by primary core: symmetry
by
the
secondary core)
(Fig.
4).
(m)
Disconnect
the
capacitor 0.001pF from
the
TPf
after the
alignments
has
been
completed.
(n)
Connect
the
capacitor
@.7
pF
) to
the
terminal
@
after the
alignment
has
been
completed.
ADJUSTING
POINTS
OSCILLOSCOPE
PATTE
R
N
ANTE
NNA
TE
R
M
INALS
DUMMY ANTEN
NA
oo o
o
SWEEP
G
EN
E
RATO
R
Fig.
2
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