Akai AA-A35 - Page 14

a
Se
(2)
Non-Active
Mode
This
is
a
mode
where
the
tuner
performance
has
been
partially
constrained.
It
is
engaged
by
detecting
an
(H]
level
of
the
line
connected
to
R7,
(A1007T
Pin
15)
of
the
subject
microcomputer,
which
has
been
brought
about
by
the
microcomputer
of
AMP
in
switching
the
input
selector
of
AMP
to
other
than
TUNER,
either
PHONO
or
CD,
and
by
juding
the
tuner
thereby
not
to
be
listened
to.
Relative
to
the
display,
the
frequency
display
will
be
extinguished,
and
bars
displayed
instead,
to
signify
a
non-active
mode.
wor sounce — pmesey ——7
cry !
Lu I
scan MODE tear
Fig. 5-7
Relative
to
the
operating
performance,
will
accept
only
the
BAND,
UP/DOWN,
and
Preset
CH
keys,
and
reject
all
the
other
keys.
5-24
Auto-Tuning
MUTING OUTPUT (R71)
Pin (4 (aioo7T)
5-2-7
Tuner
Output
Muting
This
microcomputer
will
mute
the
tuner
signal
when
the
BAND
data
or
PLL
data
is
changed
by
the
[BAND],
[UP],
[DOWN],
[MODE],
or
Preset
CH
key,
or
when
the
receiving
mode
is
changed.
In
the
muting
process,
when
50
msec
have
elapsed
since
the
initial
muting
start,
data
transfer
and
other
processings
will
be
made,
and
then,
450
msec
after
these
processes
have
been
concluded,
the
muting
will
be
disengaged.
We
will
call
the
initial
part
“pre-muting”
and
the
latter
trailing
part
“after-
muting”.
The
diagram
below
illustrates
the
above
arrangement.
BAND ]
key
INPUT
PULL
DATA
CHANGE
OZ
il
et
somsec ‘asomsec
MUTE
ON
MUTE
OFF
Fig. 5-10
As
exceptional
cases,
when
an
earlier
muting
process
is
still
ongoing
upon
receipt
of
another
key
input,
the
Pin
50
msec
pre-muting
will
be
omitted.
AUTO STOP INPUT
R91 (AlOO7T)
RADIO
starion
Eres
a
1
t
i
H
i
1
SCAN
POINTS
++
Fig. 5-8
The
starting
point
in
auto
tuning
modes
may
either
be
a
broadcast
receiving
point
or
a
point
where
no
broadcast
is
received.
Since
stopping
the
scan
merely
at
an
{H]
level
of
the
auto-stop
signal
may
therefore
cause
nonconform-
ities,
the
process
employed
is
to
stop
scanning
only
when
the
auto-stop
signal
has
first
dropped
to
an
{L]
level
after
the
scanning
start
and
then
has
climbed
to
an
[H]
level.
The
scanning
speed
is
about
100
msec
per
step.
The
step
will
be
a
single
channel
spacing
in
the
receiving
band
that
varies
by
destination.
Auto-scanning
of
LW,
however,
is
an
exception
to
this
rule
and
9
kHz
steps
have
been
assigned
to
it,
where
fixed
points
ON+2
or
ON
(N
=
an
integer)
will
be
scanned.
In
other
words,
against
any
given
point
selected
earlier
by
a
manual
scan,
the
scanning
start
when
an
auto-scanning
mode
is
engaged
will
always
be
at
a
point
9N+2
or
9N.
ont2
gintlee
Bin
422
Qn
Q(ntl)
START
9(n+2)
STATION 5-2-8 Key Processing
(1) [BAND]
Each
single
press
of
this
key
will
switch
the
band.
The
selecting
sequences
will
be
as
follows:
2-
BAND
3-
BAND
FM—>AM
FM
MW
—>LW
Fig. 5-11
(2) [UP], [DOWN]
In
a
manual
scan
mode,
each
single
pressing
of
either
of
these
keys
will
shift
the
receiving
frequency
bya
step,
and
its
continuous
depression
will
have
the
band
scanned
at
50
msec
per
step.
In
a
AUTO
scan
mode,
the
band
will
be
scanned
at
100
msec
per
step
until
a
station
is
captured,
at
which
time
an
auto-stop
of
the
scanning
will
be
exercised.
In
an
auto-scan
mode,
as
soon
as
any
other
key
than
(UP]
and
[DOWN]
is
pushed,
the
scanning
will
be
stopped
at
that
point.
O(nt 342
9(nt3)
[anata
ke
as
GL
ices
12
O
SERVICE
MANUAL
AA-A35
[Lee
Fig. 5-9