Casio SK-1 Service Manual

Filter Change-Over Circuit & Percussion Circuit
Percusston Filter
Filter
Analog
Switch
IC2
Chord Filter
K015
CPU
P03
MSM6283
•DIGS
SC
LSI
1
(Percussion
sound signal)
Melody Filter
Figure
3
Melody
or
<C
Bdss
sound
signal
Melody
sound
signal
Melody
or
<
Chord
sound
signal
^
Melody
or
Obbligato
sound Signal
The Concerimate
500
has four Envelope/Pitch
mixing circuits.
In accordance with
the mode switch
position,
signals
P03 and K01
5
turn the analog
switches on or off so that
the sound signals
pass
through the appropriate filters.
P03
1 K015
NORMAL
'
H
L
SOLO
1
SOLO
2
:
CHORD
1
L
H
I
On "NORMAL"
mode,
all
Envelope/Pitch mixing circuits generate
melody
signals,
and the signals
pass through the melody filter. When the mode switch
is at the other position,
each Envelope/Pitch
circuit
creates
different
sound signals. These signals
pass
through
corresponding filter's.
The percussion signal comes out from the CPU directly,
wherever the mode
switch position Is set.
As the signal is a stepped
waveform,
the percussion filter shapes
it.

Casio SK-1 Specifications

General

Brand	Casio
Model	SK-1
Category	Electronic Keyboard
Language	English