Akai AA-A35L User manual
• ' .
AKA.I
SERUICE
m
nuAL
•
..
• -
C
OM
PU
TER
CONTROLL.'.ED STEREO RECEIVER
MODEL
AA-A3
5
/L
•
ABBREVIATIONS FOR SERVICE MANUAL
MODEL
AA
-
A35
/ L
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Medium
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Phase
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Signal
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S\\11ch
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r
•
•
II
•
•
•
•
COMPUTER CONTROLLED STEREO RECEIVER
MODELAA-A35/L
SECTION
I
SERVICE
MANUAL
. . . . . . . . . . . . . . . . . . . . 3
SECTION
2
PARTS
LIST
. . . . . . . . . . . . . . . . . . . . . . . . . . 23
SAFETY
INSTRUCTIONS
SAFETY
CHECK
AFTER
SERVICING
Confirm the specified insulation resistance between power cord plug prongs and externally exposed parts
of
the
set
is
greater than
JO
Mohrns,
but
for equipment with external antenna terminals (tuner, receiver, etc.) and is intended for
(g
or
[Al
, specified insulation resistance should be more than 2.2 Mohrns (ground terminals, microphone jacks,
headphone jacks. line-in-outjacks etc.)
PRECAUTIONS
DURING
SERVICING
1. Parts identified by the
bi.
symbol parts are critical for safety.
Replace only with parts number specified.
2.
In addition
to
safety, other parts and assemblies are specified for conformance with such regulations as those
applying
to
spurious radiation. These must also be replaced
only
with specified replacements.
Examples:
RF
converters, tuner units, antenna selector switches,
RF
cables, noise blocking capacitors, noise
blockingfilters, etc.
3.
Use
specified internal wiring.
Note
especially:
I)
Wires
covered with PVC tubing
2)
Double insulated wires
3)
High voltage leads
4.
Use
specified insulating materials for hazardous live parts.
Note
especially:
I) Insulation Tape
2)
PVC tubing
3)
Spacers (Insulating Barriers)
4)
Insulation sheets for transistors
5)
Plastic screws
for
fixing microswitch (especially in turntable)
5.
When replacing AC primary side components (transformers, power cords, noise blocking capacitors, etc.), wrap
ends
of
wires securely about
the
terminals before soldering.
6. Observe
that
wires
do
not
contact
heat
producing parts (heatsinks, oxide metal film resistors, fusible resistors,
et
c.).
7.
Check
that
replaced wires
do
not
contact
sharp edged
or
pointed parts.
8. Also check areassurrounding repaired locations.
9.
Use
care that foreign objects(screws, solder droplets,
etc.)
do
not
remain inside
the
set.
VOLT
AGE
CONVERSION
Models for Canada, USA, Europe,
UK
and Australia are
not
equipped
with
this facility. Each machine
is
preset at the
factory according
to
destination,
but
some machines can be
set
to
110V, 120V,
220V
or
240V as required. If
your
machine's voltage can be converted:
Before connecting
the
power cord, turn the VOLTAGE SELECTOR located on
the
rear panel with a
sc
rewdriver until
the correct voltage is indicated.
2
•
•
•
::
I.
II.
m.
IV.
V.
VI.
SECTION 1
SERVICE
MANUAL
TABLE
OF
CONTENTS
SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
DISMANTLING
OF
UNIT
.....................
........
.....
5
CONTROLS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
PRINCIPAL
PARTS
LOCATIO
N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
DESCRIPTION
OF
THE
CIRCUIT
OPERATION
. . . . . . . . . . . . . . . . . . 8
5-J
AMPLIFIER P
ERFORMANCE
. . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5-2 TUNER PERFORMANCE . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . .
11
AMPLIFIER
SECTION
ADJUSTMENT
. . . . . . . . . . . . . . . . . . . . . . . . .
14
6-1
THE
LNSTRUMENT
CONNECTION
. . . . . . . . . . . . . . . . . . . . . . . 14
6-2
MAIN
AMP
PC
BOARD
ADJUSTMENT
POINTS
..............
14
6-3
POWER LEVEL
METER
ADJUSTMENT
.....
....
..
..
.......
14
VII.
TUNER
ADJUSTMENT
....................................
15
7-J
THE INSTRUMENT
CONNECTIONS
. . . . . . . . . . . . . . . . . . . . . . 15
7-2 TUNER, FRONT END,
MPX
PC
BOARD
ADJUSTMENT
POINTS
. . . 16
7-3
HOW
TO
CALL THE PRESET FREQUENCY FOR
THE TUNER
ADJUSTMENT
. .
..........
17
7-4
FM
SECTION ADJUSTMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7-5
LW
SECTI
ON
ADJUSTMENT
............................
19
7-6
AM
(MW)
SECTION
ADJUSTMENT
. . . . . . . . . . . . . . . . . . . . . . .
19
vm.
PC
BOARD
TITLES
AND
IDENTIFICATION
NUMBERS
. . . . . . . . • . . . 20
For
basic adjustments, measuring methods. and operating principles, refer
to
GENERAL TECHNICAL
MANUAL.
-------------
SERVICE MANUAL AA-AJS/L
-------------
3
I.
SPECIFICATIONS
FM
TUNER
SECTION
TUNING FREQUENCY RANGE 87
.SM
Hz
to
108
.0MHz
USABLE SENSITIVITY
(!HF)
1
l.2dBf
(300ohms) •
QUIETING SENSITIVITY
(!HF)
(S/N =
50dB
) l
6.2dBf
(Mono)/37.
2dBf
(
Stereo)
CAPTURE RATIO 1.SdB
SELECTIVITY
(!HF)
60dB (
400kHz)
IMAGE REJECTION 85dB
IF REJECTION 90dB
SPURIOUS REJECTION 90dB
AM
SUPPRESSION 60dB
S/N (!HF) 75dB (Mono)/65dB (Stereo)
HARMONIC DISTORTION 0.1% (Mono)
/0.3
% (Stereo)
STEREO SEPARATION 45dJ3 (lk.Hz)
LW
TUNER
SECTION
(AA-A35L only)
TUNING FREQUENCY RANGE
146kHz
to
353kHz
USABLE SENSITIVITY
(!HF)
8001.V/m
SELECTIVITY (
!HF
) 30dB
IMAGE REJECTION
45dB
IF
REJECTION 55dB
S/N 35dB
T.H
.D
2.0%
ANTENNA
Loop
antenna
AM
TUNER
SECTION
(
MW
for
AA-A35L)
TUNING FREQUENCY RANGE
530kHz
to
l ,
610kHz
for
USA and Canada
53lk.Hz
to
l ,
602kHz
for
other
c
oun
tries
USABLE SENSITIVITY
(IHF)
300µV/m
SELECTIVlTY (!HF) 25dB
IMAGE REJECTION 40dB
IF
REJECTION 55dB
S/N
40dB
T.H.D. 1.0%
ANTENNA
Loop
antenna
•
AMPLIFIER
SECTION
RATED POWER
OUT
PUT 8
ohms
20Hz
to
20kHz 45W x 2/0.
02
%
!kHz
53W x 2/0.
02
%
MUSIC POWER 100W
POWER BANDWIDTH
(!HF,
-
3c!B
, 8 ohms)
5Hz
to
70kHz
/0.1%
S/N PHONO 75dB
AUX
98d8
RESIDUAL NOISE
(8
ohms)
0.5mV
CHANNEL SEPARATION
(IHF)
PHONO/AUX 65dB
(!kHz
)
DAMPING FACTOR
(I
kHz, 8 ohms) 50
OUTPUT SPEAKER A
or
B 4
to
16
ohms
A+
B 8
to
16
ohms
INPUT SENSITIVITY/IMPEDANCE PHONO 2.
5mV
/1
00kohms
AUX/TAPE
150mV/47kohms
OUTPUT LEVEL/IMPEDANCE
TAPE
REC
150mV/3kohms
FREQUENCY RESPONSE PHONO (RIAA) ±0.5dB
(30Hz
to
15kHz)
AUX/TAPE 5 Hz
to
l00k.Hz,
-3dB
TONE CONTROL BASS ±
8d
B
(l
00Hz)
TREB
LE
r8dB
(l0kHz)
FILTER SUBSONIC -3dB/
18H
z
PHONO MAX. INPUT (MM)
150mV
POW
ER
REQUIREMENTS
120V
,
60Hz
for USA &Canada
220V
,
50Hz
for
Europe
except
UK
240V,
50Hz
for
UK &Australia
l I
0V/120V
/220V/240V
.
50/60Hz
switchable
for
other
countries
DIMENSIONS 440(\V) x l
l0(H)
x 345(D) mm
WEIGHT 8.4kg
• For improvement purposes, specifications
and
design
are
subject
to
change
without
noti
ce. •
---------------SER
VICE
MANUAL
AA·A35/L
----------------
4
•
J
•
II.
DISMANTLING
OF
UNIT
In
case
of
trouble, etc. necessitating dismantlin
g,
please
dismantle in the order shown in
the
photographs.
Reassemble in reverse order.
U
PP
ER
COV
ER
----=
=-:
~
--
- .
-_t' : .
.....
..
'
~
•. •
,;
,-
==
=-.::-
I
::..-
T
SCR
EW
S
2 BOTTOM COVER
T SCREWS
3
SC
REW
S T
4
T SCREWS
5
--------------
SE
RVI
CE
MANUAL
AA
-
A35
/L
--------------
5
Ill.
CONTROLS
•
Fig.
3-1
Front View
23
24
25
•
.....
..
~
....
..,
....
,~..
IC':"
~=
I
••• .-..0\o
,,
_...,
t.l
''W
..
,
.......
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1•
~"'•-"(•
10-1
""'"
l#WHt
..
111
V•
d,11111tc-tO
@ @
,--··
--~
27
l
Fig. 3-2 Rear View
1.
POWER
SWITCH
17
. ACOUSTIC
MEMORY
BUTTON
2.
TONE
CONTROL
(BASS, T R'EBLE) BUTTONS
18
. SPEAKER SELECTORS (A and B)
3.
BALANCE
BlJTTON
19
. PHONES
JACK
4.
STATION
ME
M
ORY
11
to
8 & 9
to
16)
BUTTONS
20
. PHONO JACKS
5.
BAND
SELECTOR (FM. AM(MW}. LW)
BUTTON
21.
GROUND
TERMINAL
6.
T
UNING
CONT
ROL
BUTTON
22
.
TAPE
1 (REC/
PLAY
) JACKS
7.
FL
DISPLAY
23
.
TAPE
2
(REC/PLAY)
JACKS
8.
PRESET
STAT
I
ON
BUTTO
NS 24.
VOLTAGE
SELECTOR(~
mode
only)
9.
IN
P
UT
SOURCE SELECTOR BUTTONS
25
. SPEAKER
TERMINALS
(A
and
B)
(C
D
(AUX).
PHONO. TAPE 1, TAPE
2)
26.
AC POWER CORD
10. DIRECT ACCESS
VOLUME
CONTROL
27. AC
OUTLETS
11
.
DEFEAT
BUTTON
28.
AM
STEP/FM DE-EMPHASIS SELECTOR
12. ACOUSTIC MEMO
Al
and
A2
BUTTONS
(@J
model
only)
•
1
3.
SCAN
AUTO/MANU
SELECTOR
BUTTON
29.
RESET
BUTTON
14. FM MODE
AUTO/MONO
BUTTON
30.
ANTENNA
TERMINALS
15
. SUBSONIC
FIL
TE
R
SW
ITCH 31.
CDIAUX
) JACKS
16.
SAFETY
SET/CALL
BUTTON
SERV
I
CE
MANUAL AA-A35/L
6
•
•
IV.
PRINCIPAL
PARTS
LOCATION
(!J
~
e
I -
FLD
PCB
AIDOBA502A
SUBSONIC
FILTER
SW
SW2
SPEAKER SW
SW
I
PHONE PCB
Al008A504C
HEAD PHONE JACK
JI
-MEM8RAN
VO
LUME
VR90
I
Fig. 4-1
Front
View
POWER TRANSFORMER
AA·A35T
·30
(g)
40
ID
45
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SPEAKER
PCB
50
[!;!)
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PCB
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MPX PCB CONTROL PCB
AI
008A50IB
[!1)
Al007B502B
I0
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Al008A5028
AI008
A5
03B
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AI007B507B
~IAA·A35LI
AI
008A504B
~
MAIN
AMP
PCB
Al008A50IA
[!1)
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In)
504A
IEEfil
PRE AMP PCB
Al007A503A
Fig. 4-2
Top
View
----------------SERVI
CE
MANUAL
AA·A35/L
----------------
7
V.
DESCRIPTION
OF
THE
CIRCUIT
OPERATION
5-1
AMPLIFIER PERFORMANCE
5-1-
1 General De
sc
ription
(1)
Functions
a) Input Selector Control
This microcomputers
is
capable
of
controlling
analog switch TC9I64N that serves
as
the
input selector. Three input systems that include
PHONO.
CD.
and TUNER. and two monitoring
systems that include TAPE I and TAPE 2 may
be
controlled.
b) Direct
Access
Volume Control
Reads voltages detected out
of
the sound-volume
touch control through
an
A/D convener, and sets
the electronic potentiometer
in
accordance with
the read dat
a.
In
this process, any designated
setting
will
be
reached from the earlier potentio-
meter position
by
fading
in
or out.
c) Balance Control
By
setting various
lev
el differences between
Leh
and
Reh
on
the main control, up to a maximum
of
30dB
L-R
level offsets may
be
created.
d) Tone
(BASS
/TREBLE)
Co
ntrol
Operates the tone control potentiometer
(TC9156P)
in
2dB steps up
to
a maximum
of
±I0dB. and thereby performs as
an
electronically
controlled tone circuit.
f)
Acoustic Pattern Storage
By
this function. stores
in
the microcomputer two
patterns
of
the tone control circuit settings, and
enables the instant loading
of
either
of
the stored
patterns.
g)
Volume
Co
ntrol Safety Function
With
the touch control operated direct access
sound
vo
lume system that enables the instant
setting
of
any prefer
red
sound volume
level
, the
danger exists that the inadvertent touch
of
a
higher position
of
the control will cause a sudden
emission
of
unexpectedly high sounds from speak-
ers. A time lag measure
in
the form
of
fade-in's
has been provided
to
enable coping with the
above danger, but
as
an added and positive precau-
tion, this safety function
has
been added on that
suppresses
all
sounds louder than a
level
set in
advance.
h) TUNER Direct Function
This function
will
set the input selector at TUNER
upon receiving data from the microcomputer
(A
I007T) for the tuner that
is
outp
ut
as
soon
as
the tuner
has
been operated.
5-1
-2 Key
Input
and Dynamic
FL
Display
PIN
NO
CD
®
@
0
®
©
Strobes
Key
inputs and
FL
displays are both handled dynam-
ically. and their
bas
ic clock signals generated
by
the
ITM
R interrupt (1.024 Hz) for the output
of
strobe
signal
s.
R40
R4
t
R4
2
R4
>
R5
o
R51
61f1U
<
-i..-
IIIA
)(
1
28
i,U<
:=:n _
__
n
7
______
_,n'--
--
-
Fig. 5-1
5-1-3 Acceptance
of
Key lnputs
SINGLE
PRESSING w :
__J
:
••
I
CONTINUOUS
DEPRESSIONS
I I
--
24r'!UU
_111111
1; L
I
...c--
.-.<
>oooE--
~
,OOIH
1
~0
1
:.0
1
~0
1
~0
1
)0
Fig
.
5-~
• Chatterings
will
be
absorbed for
24
msec.
• Continuous depressions
will
be
accepted first at 24
msec after the depression start, second at 500 msec
after the first, and then at every I
SO
msec thereafter.
•
All
multiple depressions shall be inhibited. Once a
multiple depression
is
made, no
key
inputs
will
be
accepted until after
all
of
the depressed keys
have
been released.
5-1-4 Key Processings
(1)
(PHONO]. (CD]
Sets the input selector (TC9I64N) for either
of
the
input modes keyed
in
, and makes due indications for
it. Nothing, however.
will
occur when the depressed
key mode has already been engaged.
When
either TAPE I
or
TAPE 2 has been keyed on,
the displays for a tape monitored input
will
be
flashed on and
off
for
IO
times at a I
/2
duty and
once every second.
to
alert the operator
of
the
ongoing tape monitoring. In addition, when serial
data
is
being transferred
to
the analog switch, the
----------------S
ERVICE MANUAL
AA-A35/l
8
•
•
•
•
•
•
electronic potentiometer will be muted,
to
prevent
the leakage
of
switching noises
to
the output circuit.
(The AA-A35/L has no "TUNER" key,
but
the neces-
sary input selecti
on
will
be made by command data
from the micro-computer
(A
I007T) incorporated
in
the tuner.)
(2) [
TAP
E I
).
[TAPE
2]
Each
single pressing
of
either key will switch its
monitoring status between
ON
and OFF from one
to
the other, and its indication also turn
ON
and OFF
accordingly.
In
addition, during the transfer
of
serial
da
ta
to
the analog switch, the electronic potentio-
meter
will
be muted
to
prevent the leakage
of
switching noises to the output.
This, however. does not apply
10
TAPE I key opera-
tions with TAPE 2
in
an
ON
mode.
(3) [VOLUME]
When
the sound volume display
is
being made, either
fades the sound volume display
is
being made, either
fades
in
or fades
out
to the touched position from
an
immediately preceding level. The phasing speed
will
be
2 dB per
60
msec. However, when the touched
position
is
above the "Safety" engaged position. the
foregoing operation will be made only up to that
"Safety" position.
As
for the display, the touched
position (within the "Safety'' range) will instantantly
be displayed upon touching.
Wh
en either the Balance
or
the Safety
Level
is
being
displayed. the display will be switched
to
the
Volume. Operations thereafter will conform with the
above process.
(4) [BALAN
CE
L
),
[BALANCE R]
When
the Balance
is
being displayed, data
will
be
transferred to provide the designated
level
offsets
between
Leh
and
Reh
of
the electronic potentio-
meter, and the display
will
also synchronize there-
with.
When
continuously depressed, however. the
potentiometer setting will start varying
at
500 msec
after the depression start, and
will
thereafter vary at
2 dB per
150
msec, but linger for 750
msec
at the
center position when passing through it. (The display
will vary at 2 dB per step
in
the immediate vicinity
of
the center position. but
at
4 dB per step
in
all
other
areas.)
Wh
en these keys are pushed while either the Volume
or
the Safety
Level
is
being displayed, the display
will
be
switched to the Balance.
(5) [
SA
FET
Y)
•
When
either the Volume
or
Balance position
is
being displayed:
A single press
of
the key
will
first have the Safety
Level
position
at
the time di
sp
layed. This display
will
revert
to
the Volume position display 5
seconds later. but
if
the Safety key
is
depressed
continuously for one second
or
longer. the display
will
be switched to that
of
the Volume. and the
Safety indicator will nash
on
and
off
every second
at
a I/2 duty. This signifies a Safety changing
mode to
have
been engaged. where any Volume
level
up
to
Max
may
be
se
lected, and the mode
wilJ
be sustained for one minute.
In
other words,
the one minute after the beginning
of
the Safety
flashing represents a Safety
Level
setting time
duration.
•
When
the Safety indicator
is
nashing
on
and off:
The Volume position touched
in
this duration
will
be
set
as
the Safety
Level
that represents the
sound volume
leve
l not be exceeded by any sub•
sequent acoustic output.
As
long
as
the Safety
Level
set
is
other than the maximum potentio-
meter position, the Safety indicator
will
be lit
steadily, but when it
is
at the maximum posiuon,
the indicator
will
go off.
(6) [BASS+), [B
ASS-I.
[TREBL
E+].
(TREBL
E-I
Each single pressing
of
one
of
these keys
will
either
raise
or
lower the electronic potentiometer for either
BASS
or TREBLE.
When
it
is
depressed contin•
uously, the first potentiometer up/down shifting
operation
will
be
performed when 500msec have
elapsed since the depression start, and the subsequent
operation
at
the rate
of
150 msec per step.
When
the
shifting passes through the center position. it will
linger there for 750 msec before moving further on.
The display
will
also vary conforming with individual
key operations.
(7) [DEFEAT]
Restores the
BASS
/TREBLE
pos111ons
all at the
center. regardless
of
their earlier potentiometer posi•
tionings.
(8) (MEMO!
Engages
an
acoustic patlern storage standby mode.
At this time, the
ACOUST
IC
MEMO
indicator
will
turn on. and the AI and
A2
mdicators
flash
on and
off
for
IO
umes at a I/2 duty m I-second cycles
(al
I Hz).
Even
before S seconds are up, the standby mode may
be
disengaged by pushing any other key than (A
11
and [A2)
(9)
[A
l
),
[A2l
•
When
at
Standby for Acoustic Panern Storage:
Stores the current
BASS
/TREBLE positions m
the memory. and
will
disengage the storage
standby mode.
•
When
in
any other mode than Acoustic Pauern
Storage Standby:
Loads the stored
BASS
/TREBLE positions. that
1s.
sets the potentiometers instantly at those posiuons
and their displays at the
same
time.
----------------
SERVICE MANUAL AA·AJS/L
----------------
9
5-1
-5
Input
Sel
ecto
r
An
alog Switch
(TC9
J64N)
Controls the electronic potentiometer (TC9 I76P) and
the rone potentiometer (TC9 l56P).
(1)
Se
ri
al Data Structu
re
The
se
r
ia
l data
is
composed
of
3 parallel bits that
include
DATA,
CK. and ST. and the numbers
of
serial
bits
of
the individual potentiometers have been made
as
follows:
TC9164N
➔
14 bits
TC9176P
➔
20 bits
.
TC9
156P ➔ I8 bits
Control lines
DAT
A and
CK
for the TC9176P and
TC9156P have been made common with control lines
ST-WR
and
CE
for A/D converter
LC79
I
0.
because
A/D conversion and data transfers to the potentio-
meters
will
never occur simultaneously. and no
changes in the status
of
potentiometers
will
take
place
as
long
as
no ST_are issued.
a) Buffers for the Input Selector Switch (TC9J64N)
MFSRD3
MFSRD2 MFSRDl
-
a:)
N
a:)
u.l
0..
IJJ
0..
"O
0
0:::
u -u N
..,
z u.l
0::: 0:::
"' w
L.l.l
..J
0:::
::, 0 z
::>
0..
::>
0..
c::
...
Cl
::>
0
<l'.
0
<l'.
::>
a:
u
!-
V)
I-
V)
!-
0 0 I I 0 1 I
ON
OFF
[Data Timing Schematic Diagram]
PIO@,@)
rrrcr
-----------
r=c
DATAI
R70,
9
11
----------
'
Po
n@,®
; n n n n n n
CKl~71,9il
~
LJ
LJ LJ
L
_________
J
LJ
L___
Pin@,@
STIR72,73
I
u
0
Fig
.
5-3
(2)
Da
ta Buffers
Data buffers for the TC9146N are formed
in
RAMs
MFSRDO
through MFSRD3, and those for the
TC9J76P and
TC9
I56P
in
RAMs
MVSRDO
through
MVSRD4. Their allocation charts are shown
in
Tables
5-1
to5-3.
MFSRDO
...
...
<f
u u u
l 0 0
_.
Fixed Data
Table
5-1
Bits
2 and 3
of
MFSRD
I w
ill
not
be
transmitted.
b) Buffers
for
the
Mas
ter Potentiometer (TC9 I76P)
MVS
R
D4
MVSRD3 MVSRD2
L R 0 2 4 6 8 0
10
20
30
40
0
c)
Bu
ffers for the Tone Potentiometer (TC9l 56P)
MVSRD4 MVSRD3
MVSRD2
+5
+4
+3
+2 +I 0 I
-2
- 3
-4
0 0
0 0
MVSRDJ
so
60 70
C1
0
MVSRDI
-5
L R
I l
I I
MVSRDO
C2
C3
c~
0 0 J
Table
5-2
MVSRDO
C1
C2 C3
0 I 0
I 0 0
Table
5-3
_.
Fixed
Data
_.
For
BASS
_.
For TREBLE
---------------
SERVICE
MANUAL
AA-A35/L
----------------
10
•
•
•
•
•
•
5-2 TUNER
PER
FORMAN
CE
5-2
-1
General Description
(1) Functions
a)
20-
Ch
or I6-Ch Random Presetting
of
Stations
When
initia
li
zed, discr~mates between A45 and
A35
/"J.
5. and
aga
inst A45, enables JOstations each
front (I to 10) and back
(1
1 to
"J.O)
or a total
of
"J.0
stations to be preset. while against A35
/2
5,
enables 8 stations each front (I to
8)
and back
(9
to
l
6)
or a total
of
16
stations
to
be preset.
The presetting permits the random storage
of
station data irrespective
of
band, and for
FM
stations. the
MONO
/STEREO segregating data
will
also be contained
in
the storage.
b) Two TuningStyles:
AUTO
and
MANUAL
The
AUTO
Scan Tuning that once the
UP/DOWN
key
is
pushed,
wi
ll
continue scanning until d
station
is
captured. and once it
is
captured,
will
stop scanning, and the
MANUA
L Tuning that
will
scan only when the key is held down, and when it
is
released.
will
stop scanning, are rhe two tuning
styles enabled.
(LW
is
shifted
in
IK
steps for
MANUAL
and
9K
steps for
AUTO
.)
c)
Sw
itching
of
MONO
and STEREO Receiving
Modes
The MONO/STEREO mode switching function
has
been incorporated for
FM
reception. and
is
also
included
in
the stored station presetting data.
5-2-2
Acc
eptan
ce
of Key lnp
ut
SINGLE PRESSING J
CONTINUOUS
DEPRESSIONS
~1
1
11
1
• Chatterings
will
be absorbed for 24 msec.
L
Fig.5-4
• Continuous depressions will
be
accepted first at
:24
msec after the depression start. second at 500 msec
after the first. and then
at
every
SO
msec thereafter.
•
Al
l
mul
tiple depressions shall
be
inhibited. Once a
mu
ltiple depression
is
made. no key inputs
will
be
accepted until after
all
of
the depressed keys have
been released.
5
-2
-3 Initial Se
ttin
g (RST Mod
e)
a)
FL
Display:
T J J
II
I
,-
,- ,
I
,_,I
,,C (\
FM
U
07L/17
/.
7u
f.llti
Fig.
5-5
b)
The received frequency
•vill
be
at the lowest
in
the
FM
band for each destination:
c) The mode
will
be
STEREO (
FM
AUTO).
d)
The scan mode
,~
i
ll
be MANUAL.
e)
All
the preset channels will be at the lowest
FM
frequency.
f)
l11e
last frequencies
of
individual bands
of
the
tuner
will
be
rhe
lowest frequencies.
5-2-4
Stat
us in a Ba
ck
up
M
od
e
Bas
ically. the status immediately before engaging the
backup
will
a
ll
be
sustained. but slight deviations
will
be
involved,
as
listed below.
a)
When
a backup mode
is
engaged during AUTO
SCAN. the scanning
will
stop.
b)
When
a backup mode
is
engaged
in
astorage stand-
by mode. the standby
will
be
disengaged.
c) The pre-backup status
wil
l
be
sustained
fo
r about
3 weeks.
5-2-5
Act
ive and
No
n
-Act
ive Mod
es
at
Tuner
(I) Active
Mo
de
This
is
a mode after the data has been transmmed
10
the microcomputer (A1007A)
or
AM
P
to
have
the
input selector
of
AMP
switched to TUNER, that is, a
mode where
all
the tuner perfom1ance
has
been
enabled.
The data for the microcomputer
of
Ai\lP
wil
l
be
transmitted from port
R4
1 (AI 007T
Pin
@)
when
Lhe
BAND
, UP/DOWN, and Preset
CH
keys have
been pushed. and its timing
wil
l be as illustrated
below.
P1n0
R4I
IAl007T
I
-
~
6m,-----;.,;
Fig.
5-6
----------------
SE
RVI
CE
MANU
AL
AA·A35/L
----------------
l l
(2) Non
-A
ctive
Mod
e
TI1is
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
2
(Al007T
Pin
15
)
of
the subject microcomputer. which
has
bee
n brought about
by
the microcomputer
of
AMP
in
switching the input
se
lect0r
of
AMP
to other than
TUNE
R. either
PH
ONO
or CD, and by juding the
tuner thereby not to be listened to.
Relative
to
the display. the frequency display
wil
l
be
extinguished. and bars displayed instead,
to
signify
a non-active mode.
,- n
I_
j_
l
.....:::
::..,
~
-CAN
M0-011
._.
.....,.
Fig. 5-7
5-2-7
Tun
er
Output
Muting
This microcomputer
wil
l 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
w
ill
be disengaged.
We
will
call
the initial part
··pre-muting'' and the latter trailing part '·after-
muting''.
The diagram below illustrates the above arrangement.
M
UTING
OUTPUT
(
R7
1)
K[Y
INPUT
RECEPTION
[
BAND ]
PULL
DATA
CHANGE
I
MONO
ISTEREO
;
Relati
ve
to the operating performance,
wil
l accept
P,n
@tA1001T
J
only the
BAND.
VP
/
DOWN.
and Preset
CH
keys, and
reject
all
the other keys.
5-2-6 A
ut
o-Tuning
P,n@
AUTO STOP
INPUT
R91 I Al
007T
I
SCAN POINTS
RAO!O
I
SU,T
ION
I I I I I
LJ
I I
I
OOmt
RAD
IO
S
TAl
ION
! l ! (1 l l
Fig.
5-8
The starting point
in
au
to
tuni
ng
modes may either
be a broadcast receiving point
or
a point where no
broadcast
is
received.
Since st
op
ping the scan merely al
an
[Hl
level
of
the
auto-stop signal may therefore cause nonconform-
ities. the process employed
is
to stop scanning only
when the auto-stop signal h
as
first dropped
to
an (L]
level
af
ter the scanning start and then has climbed
to an [HJ level.
Th
e scanning speed
is
about
JOO
msec per step. The
step w
ill
be
a sin
gle
channel spacing in the receiving
band that var
ie
s by destination. Auto-scanning
of
LW.
however,
is
an
exception
10
th
is
rule and 9 kHz steps
h
ave
been assign
ed
to it, where fixed poin
ts
9N+2 or
9N
(N
=
an
integer) w
ill
be scanned.
In
other words. a
ga
inst any g
iv
en point selected
earlier by a man
ua
l scan,
th
e scanning start when
an
auto-sc
an
ning mode is engaged w
ill
always
be
at
a
po
in
t 9N+2 or
9N
.
9n
+ 2
9n
9K
9
(n
+l)+2
9(ntll
START
9
1n+21+2
91n•2
1
___
--
4K
....,.
__
5_K_ _ ,_.
9K
MUTE OH
MUTE
OFF
Fig.5-10
As
exceptional cases, when an earlier muting process
is
still ongoing upon receipt
of
another key input, the
50
msec pre-muting
will
be omitted.
5-2-8 Key
Pr
oc
essing
(1) [
BAND
]
Each single press
of
this key
will
switch the band.
Theselecting sequences
will
be
as
follows:
2·
BAND
(2) [
UP
). (
DOW
N]
J - BAND
[FM-MW-LW7
Fig.
5-1
l
In a manual scan mode. each single pressi
ng
of
either
of
these keys will shift the receiving frequency
by
a
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
scanni
ng
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.
9
ln
+3t+2
91
n
+3
1
Fig. 5-9
---------------S
ERVICE MAN
UAL
AA
·A
3S/L
----------------
l2
•
•
•
•
•
•
(3)
Preset
CH
Key
a)
When
the
Tuner
is
in
an
Active Mode:
Except
when
at
standby
for storage, a single
pressing
of
one
of
the
preset channel keys will load
the
front
(1
to
8)
and
back (9
to
16) side channels
under
that
key alternately,
and
the
FLO
will
display
the
number
of
the
channel
thus
loaded.
When
at
standby
for storage, the frequency
currently
being received will
be
stored
in
either
the
front
(1
to
8)
or
back
(9
to
16) side
memory
until
under
the
key
that
has been pushed,
and
the
storage
standby
mode
will
then
be disengaged.
b)
When the
Tuner
is
in
a Non-Active Mode:
A push
of
one
of
the
keys will have
the
front
side
preset channel {l
to
8)
under
that
key
loaded,
and
have
data
transmitted
to
the
microcomputer
of
AMP
to
switch the input selector
of
AMP
to
TUNER.
However, when in the last active
mode
of
the
tuner, a back side
(9
to
16) channel
had
been
listened
to
,
and
that
channel
key
is
now
pushed
,
the
loading effected will
not
be
that
of
the
front
side (I
to
8)
but
of
the
back side (9
to
16)
channel.
(4) [MEMO l -8) . (MEMO 9 -16]
These are
the
keys for storing a channel frequency
data
in
the
Preset CH,
and
used for channels I
to
8
and 9
to
16
, respectively. Specifically, when
either
of
the
keys
is
pushed.
the
MEMO
Indicator
will
be
lit,
and
the
channel
number
display flashed
on
and
off,
to
alert
the
operator
as
to
which side
of
the
Preset
CH key, I
to
8
or
9
to
16,
is
being
operated.
For
I
to
8:
For9
to
16:
Fig. 5-12
The above
mode
will
be
sustained for 5 seconds,
and
the flashing repeated for
IO
times
at
a l/2
duty.
When, however,
the
Preser CH
key
is
pushed for
data
storage,
or
when
any
other
key
is
pushed.
the
storage
stan?bY
mode
will
be
instantly
disengaged.
When
the
tuner
is
in
a non-active
mode,
nothing
will
occur.
(5) (MO
DE
]
Each
single pressing
of
this
key
will switch
the
FM
reception between MONO and STEREO from
one
to
the
other.
When
the
tuner
is
in
a non-active
mode
, nothing will
occur.
{6)
[SCAN
MODE]
Each single pressing
of
this key will switch
the
scan
mode
between
AUTO and MANUAL from
one
to
the
other,
and
due
indications
made
at
the
same time.
----------------
SERVICE
MANUAL
AA-A3S/
L--
--
-
--
-
--------
13
VI.
AMPLIFIER
SECTION
A
DJUSTMENT
6-1
TH
E INSTRUMENT CONNECTION
AC
VOLTMETER
EB
OSC
SET
INPUT(CO) e ohms
OUTPUT[L
(SPEAKER
) R
o-t-0-UM...-M_Y_,.R.,_E_SI...-ST~OR
e
ohm•
AC VOLTMETER
EB
Fig. 6-1 Instrument Connections
for
Amplifier Section Adjustment
6-2 MAIN
AMP
PC BOARD ADJUSTMENT POINTS
VARTICAL
PCB
_,..
FRONT
•
VA
lb
VA
I
(~~)
(R
chi
(L
Ch
)
POWER L
EVE
L
METE
R
/'\
: I
NCREASE
B
00
6-3
POW
ER
LEVEL
ME
TE
R
ADJ
U
STMENT
Se
t DIRECT ACCESS VOLUME (MEMBRAN VOL-
UME)
to
maximum and TONEcontrol
to
flat.
Fig. 6-2 Main-Amp PCB
Supply 1 kHz
to
CD
inputjacks
(both
l
eft
and right CH)
and adjust OSC
output
so
that
the AC voltmeters
indicate 15.SV.
AdjustVRl
so
that
the POWER LEVEL
meter
indicates 30W.
---------------
SERVICE M
ANUAL
AA-AJS
/L
---
--------
-
---
14
•
•
•
•
•
VII.
TUNER
ADJUSTMENT
7-1
THE
INSTRUMENT CONNECTIONS
TEST
LOOP
ANTENNA
APPROX
600mm
SET
Leh
OR
Reh
OUTPUT
AC
VOLTMETER
INPUT
Fig. 7-1 lnstrument Connections for AM(MW,
LW)
Section Adjustment
FM
SSG
EXT
MOD
1NPUT
~-+-l--------...j....j..-+~750HMS
OU
TPUT
ANTENNA
TERMINAL
FM STEREO
GENERATOR
TP
GND
Len
OUTP
UT
Ren
OUTPUT
SET
DISTORTION
METER L
en
INPUT
FREQUENCY
COUNTER
AC
VOLT
METER
INPUT
AC
VOLT
METER
Fig. 7-2 Instrument Connections for
FM
Section Adjustment
--------------
SERVICE M
ANUAL
AA-A35/
L---------------
l 5
7-2 TUNER,
FRONT
END, MPX PC BOARD ADJUSTMENT POINTS
VC2
:L
W
SENS(HIGHJ
r--
--
-
--
--
.
T I I T 2
AA-A35L
AM(MWI
00
'
o/->~
1
0Ea'/->~
LW SENS ,
ONLY
SENS(
LO
WI
<1/
1
1
(1/
( LOW I 1
--,...-,,-------------,.---,
·
~9-,,9
~
AM
IF
I
r--..J
I
VCI
® :
vc2
T4 1 T 3 u
l!OOL2
~
VC4 ~
FM SENS
(
HIGH
J
AM(M~
) :®
r@l
!
~
SENS
(HIGH) c -
--,
LW I AM (
MW)
_q_
s
_c_;
osc
VCI
[
5[©l
T6~
(:>
TP4
AM OUT
If)
_..,
<.)~
-..:
..J
-
-
FM
SENTER
VOLTAGE
~
TP5
~
<?
TP6
~~
T7
TB
TP2
~
(:>
TP3
-
3:
0
:::
V,
z
••
UJ
If)
"'
..J
::;;
~
u.
-
..J
Tl
+
I
lHIGH)
L3
®
8 I
FM
L4
SENS
I
L5~
vc2®
L6
FM
OSC
(HIGH)
FM
STEREO
DISTORT
ION
FM
LOC
AL
OUTPUT
~
T p I
lj
;;;;:.;.==I
IC 4
TD61O2P
AM
LOCAL
FM
CENTER
VOLTAGE OU
TP
UT
FM
DISTORTION
TUNING VOLTAGE
l
FM,AM(MW),LW,
OSC
)
MPX
PCB
MPX
FREE
RUNNING FREQ
TP7
FM
STEREO
SE
PARAT
ION
...,_...
VR 2
MPX
FREE
RUNNING
FREQ
(19kHz
I
---
VR
I
(D
u
CL
0
z
w
1-
z
0
0::
LL
,...---
: INCREASE
TUNER
PCB
FRONT
Fig. 7-3
---------------SER
VICE
MANUAL
AA-A35/L
----------------
16
•
•
•
•
•
•
7-3
HOW
TO CALL THE PRESET
FREQU
ENCY
FOR
TH
E TUNER ADJU
ST
MENT
C
ONTROL
PCB
Tuner preset frequencies for adjusting RF, IF
and
FM
demodulator
are
able
to
preset as follows
insted
of
operating TUNING
control
butto
n
to
get the test
frequencies from Signal Generator.
~s
H 1/9 2/10
1 to 8
AM
AM
600kHz I000kHz
USA & CANADA
9 to
L6
AM
AM
530kHz I000kHz
1
10
8
MW
MW
603kHz 999kHz
EUROPE 3 BAND
9
IO
16 MW
MW
522kHz 999kHz
l to 8
AM AM
EUROPE 2 BAND 603kHz 999kHz
UNIVERSAL
AREA
AM AM
9 to
16
522kHz 999kHz
SHORT (MOMEN
TA
R
ILY)
[2]
TE
ST
[Q]
(Q]
[Q]
[Q]
[Q]
[Q]
[Q]
Fig. 7-4
Short-circuit momentarily
two
test
points
shown
in
Fig. 7-4. l11en select required test frequency
by
pushing
one
of
the
Preset
Station
buttons
according
to
Chart
7-1.
PRESET
STA
TION
CH
3/
11
4/
12
5/13 6/
14
7/
15
8/16
AM
FM
FM
FM
FM
FM
1400kHz 88.0MHz 90.0MHz
98
.0MHz
106
.0MHz 108.0MHz
AM
FM
FM •
FM
FM FM
l6llkHz
87.4MHz 90.0MHz
98
.0MHz 106.0MHz 108.
LMHz
MW
FM FM
FM FM FM
1404kHz 88.0MHz 90.0MHz 98.0MHz
106
.0MHz
108
.0MHz
MW
LW
LW
LW
LW
LW
16
llkHz
I46kHz
!60kHz 200kHz 300kHz
353k_Hz
AM
FM
FM FM
FM FM
1404kHz 88.0MHz 90.0MHz 98.0MHz 106.0MHz
108
.0MHz
AM
FM FM •
FM
FM
FM
I
61
lkHz
87.4MHz 90.0MHz 98.0MHz 106.0MHz
108
.1MHz
* =
FM
AUTO Chart
7-1
NOTE
: For
@]
mode
l
only,
set
AM
STEP switch
to
9kHz
position. which located
on
the
rear panel.
----------------
SE
R
VICE
M
ANUAL
AA-A35/L
----------------
l7
7-4 FM SECTION ADJUSTMENT
Step Adjustment Item Adjustment Point Result Remarks
Band
SW
to
FM
I
FM
OSC L6 12V
at
108.1MHz 108.1MHz Mono
input.
(in
FRONT
END PCB) Display
to
108.1MHz.
Connect
DC
Voltmeter
to
TP2.
FM
mode
SW
to
Mono
2 Low Range
LI
to
LS
Less
than
JOdB 90MHz. Mono
input
.
Sensitivity (
in
FRONT END :'CB)
input
from SSG Display
to
90MHz.
3% Distortion Factor.
High Range
VC!
, 2, 4 Less
than
I
0d
B 106MHz, Mono
input.
3 Display
to
106MHz.
Sensitivity (in
FRONT
ENDPCB)
input
from SSG 3% Distortion
Factor.
4
For
best Result,
Repeat
Steps 2
and
3
two
or
three
times
Middle Range Less
than
I
0dB
98MHz. Mono
input.
5 Sensitivity None Display
to
98MHz.
(Confirmation)
inp
ut from SSG 3% Distortion
Fa
c
tor.
FM
DC Voltmeter between TPS
and
TP6.
6
Center
Voltage T7,
T8
0V
indication Tune
only
noise
without
inter
-
ference from broadcasting.
98MHz,
60dB
, Mono
inpu
t.
Display
to
98MHz.
7 Distortion (Mono)
T7
,
TB
Less
than
0.3% Confirm
that
the
DC
Voltage
between 'IPS
and
'IP6 is within
0 ±0.
025V.
MPX
98MHz,
60dB
Stereo
input.
8 Free Running
VR2
l9kHz
Display
to
98MHz.
Frequency (in MPX PCB) Connect
Frequency
Counter to
TP7 (in MPX PCB).
98MHz,
60dB
, Stereo L-CH
9 Stereo Separalion VRJ More
than
38dB
(R-CH) input:
(in MPX PCB) Display
to
98MHz.
Minimum
output
of
R-CH{L-CH)
98MHz,
60dB
Stereo (L-CH
or
Tl
R-CH)
input.
10 Distortion (Stereo) (in
FRONT
END
PCB), Less than 0.5% Display
to
98MHz.
T7
,
T8
Confirm
that
the
DC
voltage
between 'IP5 and
TP6
within
0
±0.025V.
N
OTES
:
I.
Set
the
internal
modulat
i
on
signal generator
to
J
00
% {75kHz dev. (in
Europe)
40kHz
dev
.)
, l
kHz
of
each.
2.
Adjust
Tl
(Front End),
if
the
proper
distor
tion
(STEREO)
could
not
obtained
in
step
10. (Conflrm
FM
Sensitivity in case is
turned
more
than
a
half
tum).
---------------
SERVICE
MANUAL
AA-A3S/
L--------
-
----
- -
18
•
•
•
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