Korg wavestation Service Manual page 31

Then,
the indication changes to
" MARK/JUMP TO NEXT
".
After the Encoder Test
is
finished normally, press MARK/ JUMP SW
to
proceed
to
TEST
2
LCD PIXEL
TEST.
«
TEST2
:
LCD PIXEL TEST
»
1.
Confirm that all the dots in the
LCD light.
At
this time check that there
is
no patches,
etc.
in
the LCD
and
that the
contrast changes according as the
contrast VR
is
turned.
If
nothing
is
wrong with the LCD,
press MARK/JUMP SW to
proceed
to the
next.
2.
Confirm that
all the dots in the LCD
go
out.
If
nothing
is
wrong with the
LCD,
press MARK/ JUMP SW to
proceed to
TEST
3
MDE/DF88/TG88
TEST.
((
TEST
3
:
MDE/DF88/TG88 TEST
})
Connect an oscilloscope with OUTPUT
1
and turn the master VR of
WS1 to the
MAX.
1.
MDE TEST
Press SKEY1 and carry out the MDE
TEST.
(
Once TEST
3
starts, this
condition appears automatically.
)
Confirm that the
waveform like
fig-
1
is
transmitted.
If
this test
is
N. G.
,
check MDE
(
MB87405
),
D/A Converter
(
PCM54HP
)
and
the analog circuit-
If
this test is O.K.,
press MARK/ JUMP SW or SKEY
2
to
proceed to DF88
(
VDA
)
TEST.
2.
DF88
(
VDA
)
TEST
Confirm
that the waveform like
fig. 2 is
transmitted, its
level changes
according to the
passing of
the time by dint of DF88
(
VDA
)
and that
the minimum becomes
0.
If
this test
is
N. G.
,
check DF88
(
MB87727
)
and the circuit between DF88
and
MDE-
If
this test is
0.
K.
,
press MARK/ JUMP SW or SKEY
3
to
proceed
to
TG88
TEST.
3.
TG88 TEST
Confirm the waveform
like
fig. 2
is
transmitted and
its level, pitch,
etc
do not change.
If
this test
is
N. G.
,
check TG88
(
MB87726
),
WAVE ROM and the circuit
between TG88 and
DF88.
If
this test is O.K.,
press MARK/ JUMP SW or SKEY4 to proceed to DF88
(
VDF
)
TEST-
33