Adjustments (H^); Error Messages (:C7-Y Y-Tz-Y) - Yamaha SPX50D Service Manual

SPX50D
ADJUSTMENTS
1
.
PREPARATIONS
•
Turn
the
INPUT LEVEL
to
maximum.
•
Leave the
slide
switches
SW101
and
SW
1
02
on
the
AD
circuit
board
set
to
the
TEST
position.
• The
load of the
Land R
OUTPUT
con-
nectors are to
each be
srially
connect-
ed
to
a
load resistor
(
1
0k ohms)
•
After
the adjustments
have been per-
formed,
turn the
switches to
the
NOR-
MAL
position.
2.
ADJUSTMENTS
2-1
Apply an
input
signal of
-15.5dBm
at
1
kHz
to the
INPUT
connector
and
adjust
VR1
01 so that the
output
signal
is
clipp-
ing slightly
at
the L
and R
OUTPUT
con-
nectors.
Adjust
VR102
so
that
the
clipping signal
is
vertically
symmetrical.
Afterwards, adjust
VR
101
until
the
dis-
tortion
waveforms
of
the
Land R
OUTPUT
connectors
for
mininum
distortion.
And
adjust
VR103
so that
the output
signals
of
the L
and R
OUTPUT
connectors be-
come -5.5±0.5dBm.
2-2
When
the
INPUT
is
opened, the noise
le-
vels of
the
L
and R
OUTPUT
connectors
should be
less
than
-
86dBm
If
noise
levels
are
not within rated
levels,
adjust
VR
1
02
so
that the noise
levels
are
within rated values.
ERROR MESSAGES
EO
ROM
sum
check
error.
El
RAM
(CPU's) read/write
error.
E2
RAM
(IC21
1
)
read/write
error.
1
.
itfi
•
INPUT LEVEL ^
- A
y
•
SW
1
01
,
SW
1
02
"T"
miz-t
y L
t
o
•
L,
R
w
OUTPUT
ST-
"fe 'y L
T
•!> o
•
SW101,
SW102
"N"ffiiJ
LtiJ
<
C
ho
2
.
2
-
1-1
INPUT
STT
1
- 15.5dBm/1kHz
coxt}
^
mat. OUTPUT
L,
RSTWfli**^'T'LS<^^
§
i;
T
(c
VR
1
0
1
^
PS
L
fz'ik.
j;
T tc
VR102
-S-pSt-So
2 -
1-2
hcoft,
OUTPUT
L,
R
STL:iJi>T.
Mxmm
VR101
^pstSo
TLT.
OUTPUTL,
RST<7)mi]*h-
5.5±0.5dBm
h i
-5
(c
VR1 03
^PST
•2>
o
2-2
1
INPUT
OUTPUT STT6oyTX>-<;K±, -86dBm
ho
1
02 LT^
/ T
X
tcpStl)„
EO
ROM
T:n
y
X^tAXV-
El
RAM
(CPUl*]$|3)
'J-KvT
E2
RAM
(IC211)
'J-KvT
24