WK-1200
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200TONES
100 RHYTHMS
ENVELOPE
AMP ENVELOPE
000-048 DECAY
POWER
MUSICAL INFORMATION SYSTEM
PITCH ENVELOPE
049-137 SUSTAIN
00 FLAT
01-19 VIBRATO
TRANSPOSE/
TUNE/MIDI
20-49 OTHERS
REVERB
TEMPO
MODE
ACCOMP VOLUME
SYNTH
MIXER
VOLUME
IN T R O
SYNCHRO/
ENDIN
G
DEMO
REVERB
HALL
STAGE
ROOM
SYNTH
MIXER
MEMORY
STEP
FREE SESSION
SPLIT
TOUCH
RESPONSE
TONE
TIE
3
LAYER
SPLIT
MEMORY
FULL RANGE
CHORD
FINGERED
CASIO CHORD
NORMAL
RHYTHM
GM
FREE
SESSION
LAYER
MAX
CURSOR
MEMORY TRACK/DRUM PAD
CHORD/1
STEP
2
3
4
5
6
TOUCH
RESPONSE
REST
MIN
NORM
A L / F I L L -I N
-IN
VAR/FILL
ENTER
WK-1200
ELECTRONIC KEYBOARD
CONTENTS
Page
Specifications ............................................................................................................................................ 1
Block Diagram ........................................................................................................................................... 3
Circuit Description ..................................................................................................................................... 4
Adjustment .............................................................................................................................................. 12
Major Waveforms .................................................................................................................................... 13
Printed Circuit Boards ............................................................................................................................. 14
Schematic Diagrams ............................................................................................................................... 15
Exploded View ........................................................................................................................................ 21
Parts List ................................................................................................................................................. 23
SPECIFICATIONS
GENERAL
Keyboard:
Drum pads:
Tones:
Rhythm instrument tones:
Polyphony:
Digital effects:
Auto accompaniment
Rhythm patterns:
Tempo:
Chords:
Rhythm controller:
Accomp volume:
Free session
Number of patterns
Memory function
Songs:
Recording tracks:
Recording methods:
Memory capacity:
Edit function:
Demo tunes:
Synthesizer function
Parameters:
Mixer function
Channels:
Parameters:
MIDI:
Other functions
Pitch bend range:
Transpose:
Tuning:
73 standard-size keys, 6 octaves (with touch response on/off)
6
200 (128 General MIDI, 32 synthesized, 8 drum, 32 user); with layer and
split
51
24 notes maximum (12 for certain tones)
3 reverb types (HALL, STAGE, ROOM)
100
Variable (216 steps, = 40 to 255)
3 fingering methods (CASIO CHORD, FINGERED, FULL RANGE
CHORD)
START/STOP, INTRO, NORMAL /FILL-IN, VAR/FILL-IN, SYNCHRO/
ENDING
0 to 127 (128 steps)
100 (auto-accompaniment in accordance with selected chord progression)
2
6 (2 through 6 are melody tracks)
Real-time, step
Approximately 5,200 notes (total for two songs)
Equipped
2
PCM set, amp envelope set, attack rate, release rate, pitch envelope set,
pitch, level, touch sense, pan
16
Program change number, volume, expression, pan, coarse tuning, fine
tuning, on/off/solo
16 multi-timbre receive, GM Level 1 standard
12 semitones upwards and downwards
25 steps (–12 semitones to +12 semitones)
Variable (A4 = approximately 440 Hz ± 50 cents)
—1—
Terminals
MIDI terminals:
IN, OUT
Assignable terminal:
Standard jack (sustain, sostenuto, soft, rhythm start/stop)
Headphone/Output terminal: Stereo standard jack
Output Impedance: 200 Ω
Output Voltage: 4.9 V (RMS) MAX
Power supply terminal:
12 V DC
Power supply
Dual power supply system
Batteries:
Six D-size batteries
Battery life:
Approximately 2 hours (UM-1/R20) 8 hours (AM-1/LR20)
AC adaptor:
AD-12
Auto power off:
Turns power off approximately six minutes after last key operation. Enabled under battery power only, can be disabled manually.
Power consumption:
12 V --- 18 W
Speaker output:
5W+5W
Dimensions (HWD):
116.2 × 42.1 × 14.7 cm (45-13/16 × 16-9/16 × 5-13/16 inches)
Weight:
Approximately 9.1 kg (20.1 lbs) (without batteries)
ELECTRICAL
Current drain with 12 V DC:
No sound output
Maximum volume
with 24 keys from C4 to C6 pressed in Bassoon tone
Volume: maximum, Touch response: maximum
Reverb: Hall
Phone output level (Vrms with 8 Ω load each channel):
with key A5 pressed in Bassoon tone
Volume: maximum
Reverb: Hall
Speaker output level (Vrms with 4 Ω load each channel):
with key A5 pressed in Bassoon tone
Volume: maximum
Reverb: Hall
Output level (Vrms with 47 kΩ load each channel):
with key A5 pressed in Bassoon tone
Minimum operating voltage:
430 mA ± 20 %
1570 mA ± 20 %
L-ch
R-ch
165 mV ± 20 %
150 mV ± 20 %
L-ch
R-ch
5500 mV ± 20 %
5200 mV ± 20 %
L-ch
R-ch
4260 mV ± 20%
3950 mV ± 20%
6.3 V
About General MIDI
General MIDI standardizes MIDI data for all sound source types, regardless of manufacturer. General MIDI
specifies such factors as tone numbering, drum sounds, and available MIDI channels for all sound sources.
This standard makes it possible for all MIDI equipment to reproduce the same nuances when playing
General MIDI data, regardless of the manufacturer of the sound source.
This keyboard supports General MIDI, so it can be used to play commercially available pre-recorded
General MIDI data and General MIDI data send to it from a personal computer.
—2—
BLOCK DIAGRAM
Working Storage
RAM (256K-bit)
LSI4
TC55257DFL-70L(EL)
SEG1 ~ SEG40
LCD Driver
MIDI
OUT IN
P10, P13
P14, P17
LCD
LSI501
SED1278F0A
COM1 ~ COM16
Reset IC
IC2
RN5VD40AA
RESET
P23
MD0
~
MD7
MA0
~
MA14
FI0 ~ FI9
SI0 ~ SI9
CPU
Sound Source ROM
(16M-bit)
LSI3
MX23C1610MC12CA64
LSI1
KI0 ~ KI2
PB0 ~ PB3
LRCK, SO
BCK, SINK
FI10
VDD
NMI
EA0 ~
EA14
EIO0 ~
EIO7
KC0 ~ KC7
GT-913F
MA0 ~ MA19
MA0, MA1
Effect RAM
(256K-bit)
LSI5
TC55257DFL70L(EL)
Keyboard
MD0 ~ MD15
Power Switch
DSP
LSI2
PA0 ~ PA5
HG51B277FB-1
PB0 ~ PB3
Buttons
PB4
LRCK
SO
BCK
Assingnable Jack
D/A Converter
IC1
UPD6379GR
LVDD
VCC
Output
Speakers
AVDD
CVDD
VDD
Filter
Q308 ~ Q311
APO
Main
Volume
Power Amplifier
IC301
LA4620
—3—
Power Supply Circuit
Q301 ~ Q304, 306, 307
D307, 310
VC
CIRCUIT DESCRIPTION
KEY MATRIX
KC0
KC1
KC2
KC3
KC4
KC5
KC6
KC7
FI0
C1 (1)
C#1 (1)
D1 (1)
D#1 (1)
E1 (1)
F1 (1)
F#1 (1)
G1 (1)
SI0
C1 (2)
C#1 (2)
D1 (2)
D#1 (2)
E1 (2)
F1 (2)
F#1 (2)
G1 (2)
FI1
G#1 (1)
A1 (1)
A#1 (1)
B1 (1)
C2 (1)
C#2 (1)
D2 (1)
D#2 (1)
SI1
G#1 (2)
A1 (2)
A#1 (2)
B1 (2)
C2 (2)
C#2 (2)
D2 (2)
D#2 (2)
FI2
E2 (1)
F2 (1)
F#2 (1)
G2 (1)
G#2 (1)
A2 (1)
A#2 (1)
B2 (1)
SI2
E2 (2)
F2 (2)
F#2 (2)
G2 (2)
G#2 (2)
A2 (2)
A#2 (2)
B2 (2)
FI3
C3 (1)
C#3 (1)
D3 (1)
D#3 (1)
E3 (1)
F3 (1)
F#3 (1)
G3 (1)
SI3
C3 (2)
C#3 (2)
D3 (2)
D#3 (2)
E3 (2)
F3 (2)
F#3 (2)
G3 (2)
FI4
G#3 (1)
A3 (1)
A#3 (1)
B3 (1)
C4 (1)
C#4 (1)
D4 (1)
D#4 (1)
SI4
G#3 (2)
A3 (2)
A#3 (2)
B3 (2)
C4 (2)
C#4 (2)
D4 (2)
D#4 (2)
FI5
E4 (1)
F4 (1)
F#4 (1)
G4 (1)
G#4 (1)
A4 (1)
A#4 (1)
B4 (1)
SI5
E4 (2)
F4 (2)
F#4 (2)
G4 (2)
G#4 (2)
A4 (2)
A#4 (2)
B4 (2)
FI6
C5 (1)
C#5 (1)
D5 (1)
D#5 (1)
E5 (1)
F5 (1)
F#5 (1)
G5 (1)
SI6
C5 (2)
C#5 (2)
D5 (2)
D#5 (2)
E5 (2)
F5 (2)
F#5 (2)
G5 (2)
FI7
G#5 (1)
A5 (1)
A#5 (1)
B5 (1)
C6 (1)
C#6 (1)
D6 (1)
D#6 (1)
SI7
G#5 (2)
A5 (2)
A#5 (2)
B5 (2)
C6 (2)
C#6 (2)
D6 (2)
D#6 (2)
FI8
E6 (1)
F6 (1)
F#6 (1)
G6 (1)
G#6 (1)
A6 (1)
A#6 (1)
B6 (1)
SI8
E6 (2)
F6 (2)
F#6 (2)
G6 (2)
G#6 (2)
A6 (2)
A#6 (2)
B6 (2)
FI9
C7 (1)
SI9
C7 (2)
Key
Note: Each key has two contacts,
the first conatct (1) and second contact (2).
FI
Second contact (2)
First contact (1)
KC
SI
NOMENCLATURE OF KEYS
C#1 D#1
F#1 G#1 A#1
C#2 D#2
F#2 G#2 A#2
C#3 D#3
F#3 G#3 A#3
C#4 D#4
F#4 G#4 A#4
C#5 D#5
F#5 G#5 A#5
C#6 D#6
F#6 G#6 A#6
C1 D1 E1 F1 G1 A1 B1 C2 D2 E2 F2 G2 A2 B2 C3 D3 E3 F3 G3 A3 B3 C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 C6 D6 E6 F6 G6 A6 B6 C7
—4—
BUTTON MATRIX
FI10
KI0
KI1
KI2
KC0
KC1
KC2
DRUM
DRUM
PITCH
PAD 3
PAD 1
BEND
CHORD 3 CHORD 1
H
DRUM
DRUM
PITCH G
PAD 4
PAD 2
BEND
CHORD 4 CHORD 2
G
DRUM
TEMPO
PAD 5
STEP
H
CHORD 5
DRUM
TEMPOG
PAD 6
MEMORY
G
CHORD 6
PA0
FULL RANGE
PB0
CHORD
PB1
FINGERED
PB2
CASIO
CHORD
PB3
NORMAL
PA1
INTRO
NORMAL/
FILL-IN
SYNCHRO/
ENDING
VARIATION/
FILL-IN
KC3
KC4
KC5
KC6
KC7
H
ENTER
9
6
+
TONE
START/
STOP
8
3
—
RHYTHM
E
7
2
0
DEMO
F
4
5
1
TRANSPOSE/
TUNE/MIDI
PA2
TOUCH
RESPONSE
FREE
SESSION
PA3
ACCOMP
VOLUME
LAYER
SYNTH
SPILIT
MIXER
REVERB
POWER SUPPLY CIRCUIT
The power supply circuit generates five voltages as shown in the following table. VDD and VC voltages
are always generated. The others are controlled by APO signal from the CPU.
Name
Voltage
For operation of
VDD
AVDD
+5 V
+5 V
CPU, Reset IC, DSP, Sound source ROM, Working storage RAM, Effect RAM
DAC, Filter
LVDD
+5.6 V
VCC,VC
CVDD
+9 V
+5 V
LCD driver
Power amplifier, Pilot lamp
Power jack, Pedal jack, MIDI jacks, Source voltage for LCD backlight
—5—
LCD BACKLIGHT
1
2
Q502
4.7K
LHL08TB101K
1
2
L501
CVDD
2
R501
1
T501
DG
C104FA
1
2
5
(Bottom View)
CP14
5
2SD965R
3
CFL1
C516
4
7
1
3
C502
2SD965R C104M
HMBV26BG1W63N/AZ
8
C501
2
2
3
1
DE0405-979SL180J2K
2
1
1
2
9
Q501 1
NT-07
10
When voltage CVDD is supplied, transistors Q501 and 502 start oscillation.
From the oscillation voltage, transformer T501 generates about 600 V which is necessary for lighting the
backlight.
RESET CIRCUIT
When batteries are set or an AC adapter is connected, the reset IC provides a low pulse to the CPU. The
CPU then initializes its internal circuit, and clears the working storage RAM.
When the power switch is pressed, the CPU receives a low pulse of POWER signal. The CPU sends APO
signal to the power supply circuit, also sends a reset signal to the DSP.
VDD
Battery set
VDD
VDD
Reset signal
RESET
Reset IC
IC2
RN5VD40AA
POWER
PLE
CPU
LSI1
GT-913F
DSP
LSI2
HG51B277FB-1
APO
SCKO
NMI
To power supply circuit
From power switch
—6—
CPU (LSI1: GT-913F)
The 16-bit CPU contains a 1k-byte RAM, three 8-bit I/O ports, two timers, a key controller and serial interfaces.
The CPU detects key velocity by counting the time between first-key input signal FI and second-key SI from
the keyboard. The CPU reads sound data and velocity data from the sound source ROM in accordance with
the selected tone; the CPU can read rhythm data simultaneously when a rhythm pattern is selected. Then the
CPU provides 16-bit serial sound data to the DSP. The CPU also controls MIDI input/output and stores
sequencer data into the working storage RAM.
The following table shows the pin functions of LSI1.
Pin No.
Terminal
In/Out
1
TXD0
Out
Function
2
RXD0
In
3
SCK0
Out
4, 5
TXD/P13,
RXD/P14
In/Out
6
SCK1
Out
7
AVCC
In
CVDD (+5 V) source
8
AN0
In
AC adaptor detection terminal.
+5 V when the keyboard is powered by batteries and becomes 0 V
to cancel the APO function when AC adaptor is connected.
9
AN1
In
Input from pitch bender
10
AGND
In
Ground (0 V) source
11
BCK
Out
Bit clock output
12
SO
Out
Serial sound data output
13
LRCK
Out
Word clock output
14
GND
In
15, 16
XLT0, XLT1
In/Out
17
VCC
In
+5 V source
18, 19
MOD0, MOD1
In
Mode selection terminal
20
RSTB
In
Reset signal input
21
NMI
In
Power ON signal input
22
INT/P10
In/Out
Data bus for the LCD driver
23 ~ 30
FI0 ~ FI3
SI0 ~ SI3
In
Terminal for key input signal
31 ~ 38
KC0 ~ KC7
Out
Terminal for key scan signal
39 ~ 50
FI4 ~ FI9
SI4 ~ SI9
In
Terminal for key input signal
51
FI10
In
Terminal for button input signal
52
SI10/P23
Out
53 ~ 55
KI0 ~ KI2
In
Terminal for button input signal
56
MWNB
Out
Write enable signal for the DSP
57 ~ 76
MA0 ~ MA19
Out
Address bus
77
MCSB0
Out
Chip enable signal output for the sound source ROM
78
MCSB1
Out
Not used
79
MCSB2
Out
Chip enable signal output for the DSP
MIDI signal output
MIDI signal input
APO (Auto Power Off) signal output
Data bus for the LCD driver
1 MHZ synchronizing pulse output
Ground (0 V) source
30 MHz clock input/output
Chip enable signal for the LCD driver
—7—
Pin No.
Terminal
In/Out
Function
80
VCC
In
+5 V source
81
GND
In
Ground (0 V) source
82
MRDB
Out
83 ~ 98
MD0 ~ MD15
In/Out
99
PLE
Out
100
P17
In/Out
Read enable signal output for the sound source ROM
Data bus
Reset signal output for the DSP
Data bus for the LCD driver
DIGITAL SIGNAL PROCESSOR (LSI2: HG51B227FB-1)
The DSP receives 16-bit serial sound data output from the CPU and adds the selected effect to the sound data
using the effect RAM. Then the DSP provides the sound data to the DAC. The DSP also controls button input/
output.
The following table shows the pin functions of LSI2.
Pin No.
Terminal
In/Out
1 ~ 3, 80
PB0 ~ PB3
In
Button input terminals
4
PB4
In
ASSIGNABLE Jack input
5
SO
Out
Serial sound data output for the DAC
6
WCKO
Out
Word clock output for the DAC
7
VDD3
In
+5 V source
8
TEST
—
Not used
9
RESB
In
Reset signal input
10
VSS2
In
Ground (0 V) source
11, 12
XIN, XOUT
In/Out
13
WCKI
In
Word clock input from the CPU
14
SI
In
Serial sound data input from the CPU
15
BCKI
In
Bit clock input from the CPU
16
SINC
In
1 MHz synchronizing pulse input
17
VDD2
In
+5 V source
18 ~ 25
IO0 ~ IO7
In/Out
26
RCEB
Out
27
VSS3
In
Ground (0 V) source
28
AD1
In
Address bus
29
DEB
In
Data enable signal for working storage RAM
30
WEB
In
Write enable signal
31
VDD3
In
+5 V source
32
CE2
In
Chip enable signal input. High active.
33
AD0
In
Address bus
34
CE1B
In
Chip enable signal input. Low active.
Function
20 MHz clock input/output
Data bus
Chip enable signal output for the working storage RAM
35 ~ 41, 43
EIO0 ~ EIO7
In/Out
42, 44 , 4 6 ~ 4 8 ,
5 1 ~ 59 , 6 1
Data bus for the effect RAM
EA0 ~ EA14
Out
Address bus for the effect RAM
45
ECEB
Out
Chip enable signal output for the effect RAM
—8—
Pin No.
Terminal
49
EOEB
50
VSS3
60
BWEB
62, 66, 70, 74, 78
VSS2
63, 67, 71, 75, 79
VDD2
64, 65, 68, 69,
PA0 ~ PA5
72, 73
76, 77
PA6/7
In/Out
Out
In
Out
In
In
Function
Read enable signal output for the effect RAM
Ground (0 V) source
Write enable signal output for the effect RAM
Ground source
+5 V source
Out
Button scan signal output
Out
Not used
LCD DRIVER (LSI501 : SED1278F0A)
The LCD driver can drive a dot matrix LCD having 40 segment and 16 common lines. The LSI contains 240
graphic symbols in the built-in character generator ROM, and stores 80 characters in the built-in display data
RAM. In accordance with command from the CPU, the LSI is capable of displaying up to 16 characters
simultaneously. The following table shows the pin functions of LSI 501.
Pin No.
1 ~ 22,
63 ~ 80
23
SEG1 ~ SEG40
VSS
—
24, 25
OSC1, OSC2
In/Out
26 ~ 30
V1 ~ V5
In
31, 32
33
34, 35
LP, XSCL
VDD
FR, DO
—
In
—
36
RS
In
37
R/W
In
38
E
In
39 ~ 42
43 ~ 46
47 ~ 62
Terminal
DB0 ~ DB3
DB4 ~ DB7
COM1 ~ COM16
In/Out
Out
—
In/Out
Out
Function
Segment signal output
GND (0 V) source
Terminals for the built-in clock pulse generator. The external
resistor connected determines the oscillation frequency.
LCD drive voltage input.
Those voltages are used forgenerating the stepped pulse of
the LCD drive signals.
Not used
LVDD (+5 V) source
Not used
Data/command determination terminal.High: data, Low:
command
Read/write terminal. High: read, Low: write
Chip enable signal.
High: enable, the writing is done at fall edge.
Low: disenable
Not used. Connected to GND (0 V)
Data bus
Common signal/output
—9—
DAC (IC1: UPD6379GR)
The DAC receives 16-bit serial data output from the DSP. The data contains digital sound data of the
melody, chord, bass, and percussion for the right and left channels. The DAC converts the data into
analog waveforms and output them to each channel separately.
Synch signal
SCK1
SINC
Data
Data
L OUT
DAC
IC1
UPD6379GR
R OUT
DSP
LSI2
HG51B277FB-1
SO
SI
Word clock
SO
SI
Word clock
WCKO
LRCK
Bit clock
LRCK
WCKI
Bit clock
CLK
BCKI
CPU
LSI1
GT-913F
BCK
FILTER BLOCK
Since the sound signals from the DAC are stepped waveforms, the filter block is added to smooth the
waveforms.
AG
AG
AG
— 10 —
From DAC
3.9 K
25C1740SS-TP-T
22 µF
AVDD
10 K
5600 PF
0.015 µF
Q310
1K
1K
1K
6.3 V100 µ
AG
1K
10 K
AG
Q308
2700 PF
To main volume
25C1740SS-TP-T
10 V22 µ AG
2.2 K
6.3 V220 µ
AVDD
AG
POWER AMPLIFIER (IC301: LA4620)
The power amplifier is a two-channel amplifier with standby switch.
3
IN11–
5
–
IN12–
4
–
+
Input
Amp.
Pre-drive
Amp.
6
IN21+
9
+
IN21–
7
–
8
–
+
Power
Amp.
RL Short
Protector
Input
Amp.
Pre-drive
Amp.
Terminal
Protection
Circuit
PriGND
IN22–
19
Boot11
20
OUT11
21
PoGND1
22
OUT12
23
Boot12
1
VCC1
18
Boot21
17
OUT21
15
PoGND2
14
OUT22
12
Boot22
+
IN11+
Input
Amp.
Power
Amp.
Pop Noise
Prevention
Circuit
Ripple
Filter
Pre-drive
Amp.
Power
Amp.
RL Short
Protector
Input
Amp.
Pre-drive
Amp.
Power
Amp.
16
2
10
11
13
NC
DC
MUTE
VCC2
ADJ
— 11 —
ADJUSTMENT
DISPLAY PCB
1) Items to be adjusted:
Item
Measuring Instrument
Vop voltage setting
Voltmeter
2) Adjustment and Test Point Locations
(BOTTOM VIEW)
VR501
TP2 (top side)
3) Equipment connection/Procedure
Vop voltage setting
Set
Voltmeter
Output
TP2
Input
Connection
Input
Point
Input
Signal
Adjust
Output
Connection
Output
Point
VR501
Voltmeter
TP2
Adjust for
Adjust for 4.4 ± 0.1 V reading
on voltmeter.
Make fine adjustment according to the next instruction.
Eye
Watching the LCD at a 37.40° angle to the horizontal, adjust Vop
voltage so that unenergized segments are seen dimly.
37.40°
LCD
— 12 —
MAJOR WAVEFORMS
2
1
4
3
Power ON
1 Clock signal SINK
Test point T5
2 Clock signal FB1
Test point T3
3 Clock signal FB2
Test point T4
4 APO signal
JH connector pin 4
5
7
9
8
0
6
5 Key common signal KC0
JC connector pin 3
6 Key common signal KC1
JC connentor pin 4
7 Sound signal (LMEL)
Test point T2
8 Sound signal (RMEL)
Test point T1
9 Sound signal (LIN)
JK connector pin 1
0 Sound signal (RIN)
JK connector pin 2
Tone: Bassoon, Volume: Maximum
Touch speed: Maximum, Reverb: Hall
Key: A4
— 13 —
Power OFF
PRINTED CIRCUIT BOARDS
Main PCB JCM730-MA1M
3
2
7
Sub PCB JCM730-MA2M
8
1
4
5
6
Top View
9
Bottom View
— 14 —
10
SCHEMATIC DIAGRAMS
Main PCB JCM730-MA1M
8
2
7
3
4
1
5
6
— 15 —
Sub PCB JCM730-MA2M
10
9
— 16 —
Console PCBs JCM730-CN1M/CN2M/CN3M/CN4M
— 17 —
LCD Driver PCB JCM730-LCD1M
— 18 —
Keyboard PCBs JCM731T-KY1M/KY2M/KY3M
— 19 —
EXPLODED VIEW
34
R-1
18
27
29
23
25
19
30
28
28
26
32
11
24
31
7
10
22
15
21
16
19
22
17
33
20
12
18
4
3
6
R-2
1
5
2
R-3
6
14
13
R-5
35
8
R-4
9
— 21 —
PARTS LIST
WK-1200
Notes:
This parts list does not include the cosmetic parts, which
parts are marked with item No. "R-X" in the exploded
view.
Contact our spare parts department if you need these
parts for refurbish.
1.
Prices and specifications are subject to change without prior notice.
2.
As for spare parts order and supply, refer to the
"GUIDEBOOK for Spare parts Supply", published
seperately.
3.
The numbers in item column correspond to the same
numbers in drawing.
Item
1
LSI1
LSI2
LSI3
LSI4/LSI5
IC1
IC2
X1
X2
2
IC301
IC302
Q301, Q306
Q302/304
Q307-Q312
Q303
Q307
D301/302
D303 - D306
D308/311
D310
J301
J302
J303
J304
3
4
5
6
LSI501
Q501/502
Q503
Q504
D501
D502
C501
L501
T501
VR501
7
D601
D602 - D644
LED601
VR601
8
D809 - D946
9
D801 - D808
Code No.
MA1M PCB
6925 8890
2012 5005
2012 4494
2012 5665
2012 5572
2105 4746
2012 1883
2590 2699
2590 2700
MA2M PCB
6925 8920
2114 1883
2114 1421
2251 0672
Parts Name
Specification
Q
R
PCB/ASSY (MA1M)
LSI,CPU
LSI,DSP
LSI/MASK-ROM
LSI/S-RAM
LSI/D/A CONVERTER
IC/MOS
OSCILLATOR/CERAMIC
OSCILLATOR/CRYSTAL
M240676*1
GT913F(T)
HG51B277FB-1
MX23C1610MC-12CA64
TC55257DFL-70L(EL)
UPD6379GR-E1
RN5VD40AA-TR
EFO-B2005E0
XA10412
1
1
1
1
2
1
1
1
1
A
A
A
A
A
A
A
A
A
PCB/ASSY (MA2M)
IC/LINEAR
IC/PHOTO COUPLER
TRANSISTOR
M140624*1
LA4620
PC900V
2SB1548-P.CS
1
1
1
2
B
A
B
B
2252 0154 TRANSISTOR
2SC1740SS-TP-T
8
B
2251 0910 TRANSISTOR
2360 1085 DIODE/ZENER
2390 1463 DIODE,SHOTTKY
2SB1237Q,R-TV2-T
HZS6B1LTD-T
SB20-03B
1
1
2
A
A
B
2390 1344 DIODE
1SS133T-77-T
6
B
RD5.1JSB1-T1-T
HEC2305-01-920
YKB21-5006
YKB21-5010
YKF51-5051
1
1
1
1
1
A
B
B
B
B
M240682*1
M240678*1
HMBV26BAG63N/AZ
HRB-0256
SED1278F0A
2SD965-R(TA)
2SA933ASTPR
2SC1740SR-TP-T
HZS6A2LTD-T
1SS133T-77-T
NNMTP104K50-T
LHL08TB101K
NT-07
EVN-D8AA03B53
1
1
1
2
1
2
1
1
1
1
1
1
1
1
B
B
A
B
A
B
B
B
B
B
C
C
B
B
M140606*1
MTZJ5.1AT-77-T
1SS133T-77-T
LN28RPX-(TT)
EWASC2C95B23
1
1
43
1
1
B
B
C
C
B
M140614*1
1SS133T-77-T
M340666*1
1SS133T-77-T
1
138
1
8
B
B
B
B
2360 2233 DIODE/ZENER
3501 5012 JACK/POWER
3612 0665 JACK
3612 0789 JACK
3501 4816 JACK/DIN
BL ass'y
6925 8950 BL ASSY
6925 8960 PCB/ASSY (LCD1M)
3122 3524 LAMP,FLORESCENT
5861 3522 CUSHION/LAMP
2012 5569 LSI/LCD DRIVER
2253 0710 TRANSISTOR
2250 1577 TRANSISTOR
2220 1409 TRANSISTOR
2360 3056 DIODE/ZENER
2390 1344 DIODE
2830 9236 MYLAR CAPACITOR
3841 1197 COIL
3012 1470 TRANS/INVERTER
2775 0994 POTENTIOMETER
CN1 ~ CN4 PCBs
6925 8970 PCB/ASSY (CN1,2,3,4)
2360 1729 DIODE/ZENER
2390 1344 DIODE
2370 0343 LED
2765 2178 POTENTIOMETER
KY PCBs
6925 8930 PCB/ASSY (KY1,2)
2390 1344 DIODE
6925 8940 PCB/ASSY (KY3)
2390 1344 DIODE
Notes:
Q – Quantity per unit
R – Rank
— 23 —
Item
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
Code No.
Keyboard
6922 2720
6922 2730
6906 8481
6926 2500
6926 2510
Bender
2765 1141
6906 8492
6911 5261
Panel
3831 1074
3831 1075
3335 6571
6909 5890
6921 5031
6925 9380
6925 9390
6925 9400
6925 9410
6925 9420
6925 9430
6925 9440
6925 9450
6925 9460
6925 9470
6926 2540
6925 9340
6906 8456
Accessory
6925 9770
Notes:
Part Name
Specification
Q
R
KEY SET/LT WHITE
KEY SET/LT WHITE
KEYSET/BLACK 10P
RUBBER/CONTACT
RUBBER/CONTACT
M312118*1
M312118*2
M140369A-3
M240699-2
M240700-2
5
1
3
5
1
A
A
A
A
A
POTENTIOMETER
KNOB/BEND
SPRING/BENDER
RK1631110-50KB
M31488B-4
M41949A-1
1
1
1
B
B
C
SPEAKER
SPEAKER
LCD
SWITCH/SLIDE KNOB
KNOB
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/BUTTON
RUBBER/INTERCONNECTOR
PANEL/DISPLAY
COVER/BATTERY
S12J82A
S05JH37A
LD-B10060E
CSB-12D
M311859A-1
M240641-1
M240636-1
M240638-1
M240640-1
M240640-2
M240635-1
M240639-1
M240634-1
M240632-1
M240633-1
M440459-2
M340642-1
M311164F*12
2
2
1
1
2
1
1
1
1
1
2
1
1
1
1
2
1
1
B
B
A
B
B
B
B
B
B
B
B
B
B
B
B
B
C
B
STAND/NOTE
M140586-1
1
B
Q – Quantity per unit
R – Rank
— 24 —
8-11-10, Nishi-Shinjuku
Shinjuku-ku, Tokyo 160, Japan
Telephone: 03-3347-4926
MA0700571A