Sony ICF-111B - SECTION 3 CIRCUIT ADJUSTMENTS; 3-1. FM IF ALIGNMENT

‘CF-111B
2-5.
DIAL
CORD
STRINGING
Preparation
1.
Remove
the
chassis.
2.
Cut
the
dial
cord
by
the
specified
length
as
shown
in
Fig.
2-11.
7-633-120-52 |
dial cord, 0. 251 mm dia.
3-434-136
shaft, tuning
@) 7 turn
see note.
7-623-605
SEZ Ley eyelet
3-825-636°
Stringing
1.
Fix
the
dial
cord
to
the
protrusion.
(step
G)
)
and
string
the
cord
in
numerical
order
as
shown
|
in
Fig.
2-11..
Note:
Pass
through
the
dial
cord
at
step
between
the
two
cords
of
steps
2)
ie
@
and
as
shown
in
Fig.
2-12.
2.
Fasten
the
both
knots
with
a
contact
cement.
Pointer Setting
1.
Rotate
-the
tuning
shaft
counterclockwise
to
the full.
2.
Set
the
pointer
to
the
slit
as
shown
in
Fig.
2-12.
3-837-668
pointer
slit
(pointer setting
Position)
puNey
®)
bs
the
cord
with
tuning
shaft,
dial
drum
at
fully
uf
‘the
eyelet.
counterclockwise
position.
X-38376-85-1 3.097.619
sub-chassis drum, dial (at fully clockwise position)
Fig. 2-17. Fig. 2-12.
SECTION 3
CIRCUIT ADJUSTMENTS
3-1.
FM
IF
ALIGNMENT
oscilloscope
Test Equipment/Tools Required:
10.7 MHz sweep/marker generator
Oscilloscope
0.0] uF ceramic capacitor
Slot screwdriver
x * %£+
Preparation:
1. Sweep/marker Generator Connection:
Across the tuning capacitor as shown in
Fig. 3-1.
Oscilloscope Connection: Record out jack.
Sweep Generator Center Frequency: 10.7 MHz
Marker Generator Frequency: 10.7 MHz
Band Selector: FM
VOL
Control:
Scale
10
faanun
volume)
TONE Control: en
eZ LER
Ft Oe dee
AFC Switch: OF
from
—
/
sweep/marker
i}
S
we
generator
A\
|
my
BT
WY
Ea
a
i
:
|
WY
iil
Fig.
3-1.
Sweep/maker
generator
connec
tion
sweep/marker
generator
Fig. 3-2. Fm i-f. alignment setup
70.7 MHz
\, marker
Fig,
3-3.
Response
curve
_
Fig.
3-4.
““S”
curve
Procedure: |
1.
Turn
the
core
of
discriminator
-transf
ormer
(IFT F5) fully counterclockwise. _
2.
Turn
the
core
of
fm
i-f
transformer
(IFT
FI,
IFT F2, IFT F3) and discriminator transformer
(IFT
F4)
to
obtain
the
maximum
amplitude
response
curve
shown
in
Fig.
3-3.