Sony ICF-7800 Service Manual

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ICF-7800
3-2. AM SECTION
Sw
AM rf signal
generator
CON
30% amplitude
modulation by
400 Hz signal
main board — conductor side —
MW
AM rf signal
generator
Put
the
lead wire
VOM
(1)
4 ntenna close to T . —, ac.
ai { ange. 0.5-5V 7]
C
30% amplitude
modulation by
400 Hz signal
Note:
¢
Repeat
the
procedures
in
each
adjustment
several
times,
and
the
frequency
coverage
and
tracking
adjustments
should
be
finally
done
by
the trimmer capacitors.
e
After
adjusting
the
SW
frequency
coverage
and
tracking
adjustments
perform
the
MW
adjust-
ments.
EARPHONE
MW TRACKING ADJUSTMENT
Adjust for a maximum reading
on VOM (1).
1,400 kHz
600 kHz
Adjust
for
a
maximum
reading
on
VOM
(D).
468 kHz
ADJUSTMENT
on VOM ‘@) 7
1,680 kHz 520 kHz
Adjust
for
a
maximum
reading
on
VOM
().
MW
FREQUENCY
COVERAGE
ADJUSTMENT
SW
FREQUENCY
COVERAGE
Adjust for a maximum reading
12.3 MHz
3.8 MHz
ICF-7800
3-3. TIMER ADJUSTMENT
Setting:
POWER switch: ON
Timer
set
control:
minimum
Procedure:
1.
Turn
the
timer
select
switch
from
OFF
to
MINUTES
and
make
sure
that
the
radio
operates
after
three
minutes.
Note:
If
necessary,
adjust
VR5
and
repeat
step
L,
2.
Turn
the
timer
select
switch
to
HOURS
and
make
sure
that
the
radio
operates
after
fifteen
minutes.
Note:
If
necessary,
adjust
VR6
and
repeat
step
2.
MAX
timer set control
(VR4) MIN
VR5
(If
the
radio
does
not
operate
even
after
three
minutes,
turn
VR5
clockwise.)
timer select
switch (S2)
MINUTES < OFF > HOURS
VR6
(If
the
radio
does
not
operate
even
after
fifteen
minutes,
turn
VR6
counterclockwise.)

Sony ICF-7800 Specifications

General

Brand	Sony
Model	ICF-7800
Category	Receiver
Language	English