Adjustment Procedure - Korg MONO/POLY Service Manual

8.
ADJUSTMENT PROCEDURE
Caution: This unit has been precisely
adjusted
at
the factory before
shipment. Therefore,
absolutely
do
not
turn
any
variable resistors
other than those required for servicing.
Furthermore,
please
allow
thirty
minutes
of
warm-up
time
after
turning
on
the
power
before beginning
check
or adjustment.
Please refer
to the separate
VR
location
chart.
Cs
Normal
setting
1.
POWER SUPPLY
adjustment (KLM-376).
Connect
DVM
to
KLM-356;
GND
is
J12.
1)
-15V: Check
J11 with
DVM
and confirm
-15V
(±0.01V).
Adjust
KLM-376 VR-3
if
necessary.
2)
+15V: Check J40
with
DVM
and confirm
+15V
(±0.5V).
3)
+5V: Check
left
side
of
R54
(J39) with
DVM
and
confirm
+5V
(±0.02V). Adjust
KLM-376 VR-2
if
necessary.
2.
KEY
ASSIGNER
adjustment
(KLM-356).
1
)
Assignor
slope.
CV1
output:
Short
the
TUNE
POINT;
connect
DVM
to right side
of
KLM-356 R8 (GND
is
J12);
change
TRANSPOSE SW
position
in
the order
UP
-*
DOWN
-»
NORMAL
and adjust to obtain the
values
shown
in
the chart.
TRANSPOSE
VR
CV1
UP
HI
ADJVR-1
+10.583
±1mV
DOWN LOW AD
J
VR-2
+0.000
±1mV
NORMAL
MIDADJVR-3
+5.250
±1mV
2)
Open
the
TUNE
POINT
and confirm keyboard
CV
as
shown.
KEY TRANSPOSE
CV
Absolute value
±10mV
Slope
±2mV/Oct.
C2
DOWN
1.000V
C2
NORMAL
2.000V
C3
NORMAL
3.000V
C4
NORMAL
4.000V
C5
NORMAL
5.000V
C5 UP 6.000V
3.
PITCH
adjustment
(stretch
tuning) (KLM-354).
1)
OFFSET
adjustment
Check
KLM-398
lead
wire connection points with
DVM
and confirm
that
each
VCO
offset voltage
is
±0.1mV. Adjust the
KLM-398
VR
if
necessary..
Color code:
VCO
1
—
Red
VCO
2
—
Yellow
VCO
3
+
Blue
VCO 4-*
Gray
2)
VCO-1 adjustment
Settings:
VC01 LEVEL
10
VC02-4 LEVEL
MASTER TUNE
center
TRANSPOSE
NORMAL
DETUNE
WHEEL
BEND,
MG
.
VCF
Connect
properly calibrated
WT-12
to
SIG
OUT
or
PHONE
OUT
and
adjust as
follows.
Set
WT-12
to
METER
function
and
set
chromatic
dial
to
A
#
.
WT-12
OCTAVE
VCO-1
OCTAVE
KEY
Meter
Indication
(cents
f
VR
M(L)
16' A*4
VR102
LL 16' A*,
-7 (-5~-
10)
VR103
M(L)
2' A*,
VR101
HH
2'
A#
4
+7(+5~+10)
VR104
The 2'
A
#
3
and
A
#
4
pitch indications
should
ideally
be
+4
cent
and +7
cent, respectively.
20