Marantz 2245 - AM Alignment Procedures; AM IF Alignment; AM Frequency Range and Tracking Alignment; FM Alignment Procedures

}
11. “AM Alignment Procedure
AM fF Alignment
1.
2:
Connect
a
sweep
generator
to
the
J151
and
an
alignment
scope
to
the
J162.
Rotate
each
core
of
IF
transformer
L153
and
L154
for
maximum
height
and
flat
top
symmetrical response.
AM
Frequency
Range
and
Tracking
Alignment
1.
Ww
6.
Set
AM
signal
generator
to
525KHz.
Turn
the
tuning
capacitor
fully
closed
(place
the
tuning
pointer
at
the
jow
end.)
and
adjust
the
oscillator
coil
L152
for
maximum
audio
output.
.
Set
the
signal
generator
to
1650KHz.
Place
the
tuning
pointer
in
the
high
frequency
end
and
adjust
the
oscillator
trimmer
on
the
oscillator
tuning
capacitor
for
maximum
audio
output.
.
Repeat
the
step
1
and
2
until
no
further
adjustment
is
necessary.
_
Set
the
generator
to
GOOKHz
and
tune
the
receiver
to
the
same
frequency
and
adjust
a
slug
core
of
AM
ferrite
rod
antenna
and
RF
coil
L151
for
maximum
output.
_
Set
the
generator
to
1400KHz
and
tune
the
receiver
to
the
same
frequency
and
adjust
both
trimming
capacitors
of
Antenna
and
RF
tuned
circuit
for
maximum
output.
Repeat
the
step
4
and
5
until
no
further
adjustment
is
necessary.
Note:
During
tracking
alignment
reduce
the
signal
generator
output
as
necessary
to
avoid
AGC
action.
12. FM Alignment Procedure
1.
2.
Connect
a
FM
signal
generator
to
the
FM
antenna
terminals
and
a
oscilloscope
and
an
audio
‘distortion
analyzer
to
the
tape
output
jacks
on
the
rear
panel.
Set
the
FM
SG
to
87.5
MHz
and
provide
about
3
to
5
pV,
Place
the
tuning
pointer
at
the
low
frequency,
end
by
rotating
the
tuning
knob
and
adjust
the
core
of
oscillator
coil
L104
to
obtain
maximum
audio
output.
_
Set
the
FM
SG
to
108.5
MHz
and
provide
about
3
to
5
uvV
output.
Rotate
the
tuning
knob
and
place
the
tuning
pointer
at
the
high
frequency
end
and
adjust
the
trimming
capacitor
C106
for
maximum
output.
.
Repeat.
the
step
2
and
3
until
no
further
adjustment
is
necessary.
Set
the
FM
SG
to
90
MHz
and
tune
the
receiver
to
the
same
frequency.
Decrease
signal
generator
output
until
the
audio
output
level
decreases
with
the
decreasing
generator
output.
Adjust
the
antenna
coil
L101,
RF
coil
L102,
L103
and
‘F
transformer
L105
for
minimum
audio
distortion.
:
Set
the
FM
SG
to
106
MHz
and
tune
the
receiver
to
the
same
frequency.
Adjust
the
trimming
capacitor
C102,
C104
©
-and
C105
for
minimum
distortion.
.
Adjust
the
secondary
core
(black)
of
discriminator
transformer
L501
so
that
the
center
tuning
meter
pointer
indicates
its
center
at
no
signal
applied.
Set
the
FM
SG
to
98
MHz
and
increawe
its
output
level
to
1KuV
and
tune
the
receiver
to
the
same
frequency
so
that
the
center
tuning
meter
pointer
indicates
its
center.
Adjust
the
primary
core
(pink)
of
L501
for
minimum
distortion,
13.STEREO Separation Alignment
1.
Set
the
FM
SG
to
provide
1
kuV
at
98
MHz.
Tune
the
receiver
to
the
same
frequency
so
that
the
center
tuning
meter-pointer
indicates
its
center.
_
Modulate
the
FM
SG
with
stereo
composite
signal
consisting
of
only
subchannel!
signal
(of
course
a
pilot
signal
must
be
included).
Adjust
the
core
of
L301
for
maximum
audio
output,
then,
modulate
the
signal
generator
with
a
stereo
composite
signal
consisting
of
only
L
channel
signal
and
again
adjust
the
core
of
L301
for
maximum
audio
output.
.
Adjust
the
trimming
resistor
R365
for
maximum
and
same
separation
in
both
channels.
£2