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1-2 Adjustment
of
lF
Section
-1.
Connect
the
sweep generator
output
to
TPS
and
oscilloscope's
vertical terminal to
TP6.
Turn
the
tuning
knob of the
set
fully
clockwise.
2.
When
the
sweep generator
f
requency
is
set
to
452.5KH2 and its
output
level
is increased,
a
waveform
as
shown
in
Fig-
2
is
obtained.
Keep
the output
of
SSG
as
small
as
possible and
the
vertical gain
of
oscillosc()pe
as
large
as
possible.
3.
Adiust
the
cores
of
I
FT4 and
lFT5
of
obtain
maximum
height
of
the waveform
with
good symmetry.
1-3
Tracking
adjustment
Apply the output
of
SSG
to
the
set
through
dummy
load-
Bring
the
set's
dial
pointer
to
the
maximum
frequency
point
on the
dial
and
set
the
AM
SG
to
1620KH2.
Adiust the
OSC
trimmer
(TC6l
to
receive
162OKHz-
Next set
the
dial
pointer
to
the
left
end
(minimum
receiving
frequencyl,
set
the
SSG
signal
to
520KHz,
and
adjust
L4
to
receive
this
signal.
Repeat these
adiustments
2
-
3
times
so
that
the
receiving
band
width
becomes
52OKHz
-
1620KH2.
Now
adjust
the ANT
trimmer (TC4)
and RF
trimmer
(TC5)
on
the
same
frequency so
that
the
Audio
output
becomes
maximum.
15
-
20dB
output
of
SSG
is
suitable
for
the adiustment.
The
volume
and tone
controls must
be
at
maximum
position.
2.
Adjustment
of
FM tuner
2-1 lnstruments
required
FM standard
signal
generator
(SSG)
FM
lF
sreep
generator (10.7MH2)
Oscilloscope
Dummy load
(4Sr)
VTVM
2-2
Adjustment
of
lF
section
1.
Connect
the
sweep generator
output
to TPI
and
oscilloscope's
vertical terminal
to
TP2.
Turn the tuning knob of
the
set
fully
clockwise.
2.
With
the
sweep
generator frequency set
of
10.7MHz
when
the
output
level
of
the
sareep
generator
is
gradually
increased, waveform shown
in
Fig.
3 appears
on
the CRT
screen.
Now perform the following
adjustment.
Keep
the
FM
SSG
output
as
small
as
possible
and
the
vertical gain
of
oscilloscope
as
large
as
possible.
3.
Adjust the
core
(green)
of lFTl
for
maximum
height
of
the
waveform
with
good symmetry.
Adjust the
core (blue)
of
lFT3
for
maximum
height
of
the waveform.
4.
Connect
the
vertical terminal
of
oscilloscope
to
TP3.
Adiust
the
core
(black)
of
lFT3
for
good
linearity
and
good
symmetry of
the s-curve.
2-3
Tracking adjustment
1.
Turn
the
tuning knob
fully
counterclockwise
(lowest
receiving
f
requency
position).
Adjust
the
OSC
trimmer
(TC3)
to
receive 87.5MHz
from
the
FM
SSG.
2. furn
the
tuning knob
to
receive
98MHz.
Set
the
output
of
FM
SSG
ro
approximately
lOdB and adjust
the ANT trimmer
(TC1) and RF trimmer
(TC2) to
obtain maximum
audio
output.
At
this time, the
volume
control
and tone
control
knobs must
be
at maximum position.
2-4
MPX section adjustrnent
1.
Turn the
ST-MO
witch
OFF.
(Monoral
reception).
Connect
the
oscilloscope vertical
input
to
TP.4
and
apply a precalibrated 19KHz
signal (stereo
modulator
calibration
use
signal)
to
the horizontal input.
Adiust
the
semi-f
ixed
control
VR5 so that
the
Lissajuous
waveform
becomes
almost stationery.
(
lf
a
frequency counter
is
available, connect
it
to
TP.4
and adiust
VR5
so
that
the
frequency
becomes
exactly
19.OKHz).
-Adiustment
of
the
frequency
of
voltage
controlled
oscillator
(vco)-
2.
Connect
the
stereo modulator
to
FM
SSG
and set
to
the
specified modulation
depth (pilot
signal
7.5KHz).
Turn the
ST-MO sryitch
ON.
(Stereo
receptionl.
Set
the
SSG
output to
about 25d8.
Adjust the
semi-fixed
control VR4 by turning
it
in the
counterclockwise.
direction
to
a
position
where the ST
indicator
lights.
-Adjustment
of
lndicator
lamp sensitivity-
3.
This adjustment
of
lamp (lighting) sensitivity
must
be
performed
after the
adjustment
of
VCO
frequency.
The sensitivity
increases
when
VR4
is
turned
counter-
clockwise and
increases
when
VR4
is
turned to
clock-
wise
direction.
t
Betore
adjustrnent
Alter
adiustrnent
lFis.ql
Does
not
become
perfectly round
because
the
Lissajuous
figure
is
formed
by the
rectangular
wave-
form
(TP.4
outputl
and
sinusoidal
waveform
(calibra-
tion
use
19KHz signal).
ffi
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