Casio CZ-1 Service Manual And Spare Parts List page 124

25-6.
VCA
Offset
Voltage
Adjustment
VCC
(
1 )
Connect
a digital
voltmt
ter
as indicated in
tha following uble.
(Refer to
checkpoing (5)
and
(§)
on
page 4)
Connection point
\
VR
to bt adjusted
Pin
1
of
opamp and pin
(|)
of
VCA
(GNO)
j
VR2
Pin 7 of
opamp
and pin
®
of
VCA
(GNO)
VR3
(2)
While the
test
unit
is
not producing
any sound,
adjust
VR2
and
VR3
so that digital
voltmeter reading
isO±3mV.
Note:
Be
sure
to use a
digital
voltmeter.
25-6.
BBO
Adjustment
(
1
)
Connect an
oscilloscope as
shown
in
the
Uble
below.
(Refer to
checkpoint®,®
and
(5)
on page
12)
Connection point
(MA2M
PCB) Adjustment
VR
Canter
terminal of
VR1
and
pin
1
of
BBO
MN3209-1 (GNO)
VR1
Center terminal of
VR2
and
pin
1
of
BBO MN320B-2 (GNO)
VR2
Center terminal of
VR3
and pin
1
of
BBO MN3209-3 (GNO)
VR3
VR
7
Center
1MA2M
PCB]
(2)
Set the oscilloscope
on
AC
range, 0.1 V/div,
and
10jiS/div,
then observe the
waveforms.
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