Casio CTK-480 User manual

ELECTRIONIC KEYBOARD
CTK-480
CTK-480
0
5
1
6
2
7
3
8
4
9
MULTI FUNCTION DISPLAY
POWER/MODE
FINGERED
CASIO CHORD
NORMAL
ON
OFF
VOLUME SYNCHRO/
FILL-IN START/ STOP
TEMPO
⁄ 
¢ 
⁄ 
TRANSPOSE/TUNE
sAm 
00 sAm 1
01 sAm 2
02 zL[gN 
03 X^WIsAm 
04 GNgbNsAm 1
05 GNgbNsAm 2
06 GNgbNsAm 3
07 GNgbNsAm 4
08 n[vVR[h 
09 NuGNg 
IK 
10 GNgbNIK 1
11 GNgbNIK 2
12 GNgbNIK 3
13 GNgbNIK 4
14 ‘[‘IK 
15 pCvIK 
16 [hIK 
17 AR[fBI 
18 ohlI 
19 n[jJ 
M^[ / x[X 
20 KbgM^[ 
21 AR[XeBbNM^[ 
22 WYM^[ 
23 GNgbNM^[ 
24 ~[gM^[ 
25 fBXg[VM^[ 
26 Ebhx[X 
27 GNgbNx[X 
28 Xbvx[X 
29 oW[ 
XgOX / ATu 
30 oCI 
31 ‘F 
32 n[v 
33 XgOX 1
34 XgOX 2
35 XgOX 3
36 VZXgOX 1
37 VZXgOX 2
38 NCA 
39 {CX 
uX 
40 gybg 
41 ‘[o 
42 uXZNV 
43 t‘z 1
44 t‘z 2
45 uX 1
46 uX 2
47 VZuX 1
48 VZuX 2
49 VZuX 3
[h / pCv 
50 \vmTbNX 
51 AgTbNX 
52 ei[TbNX 
53 I[{G 
54 Nlbg 
55 sbR 
56 t[g 
57 R[_[ 
58 t[gATu 
59 zCbX 
VZTEh 1
60 VZ[h 1
61 VZ[h 2
62 VZ[h 3
63 VZJIy 
64 VZpbh 1
65 VZpbh 2
66 VZpbh 3
67 OXn[jJ 
68 Jg[t@[ 
69 VZx[X 
VZTEh 2
70 p[hbv 
71 RY~bNTEh 
72 TEhgbN 
73 Xy[Xpbh 
74 VZ SFX
75 ł˚„ 1 ( Ł¤ )
76 ł˚„ 2 ( db )
77 ł˚„ 3 ( F )
78 ł˚„ 4 ( Cx[_[ )
79 ł˚„ 5 ( t@j[ )
C[ 
80 XgOXsAm 
81 XgOXGs 
82 NCAGs 
83 NCAIK 
84 XgOXM^[ 
85 XgOXn[v 
86 uXXgOX 
87 oCupbh 
88 12 •M^[ 
89 NCAXgOX 
Xvbg 
90 x[X / sAm 
91 x[X / Gs 
92 x[X / oCu 
93 x[X / KbgM^[ 
94 x[X / fBXg[VM^[ 
95 XgOX / sAm 
96 XgOX / gybg 
97 rutH 
98 }o 
99 p[JbV 
100 TONES
¢ 
TONE RHYTHM SONG
TONE
RHYTHM
|bvX 
00 |bvt[W 
01 o[h 
02 |bvo[h 
03 bv|bv 
04 \Eo[h 
05 t@L[|bv 
06 16 r[g 
07 8 r[g 1
08 8 r[g 2
09 |bvX 
bN 
10 bNc 
11 X[bN 
12 \tgbN 1
13 \tgbN 2
14 tH[L[|bv 
15 60's \E 
16 bN 
17 wr[^ 
18 50's bN 
19 VJSu[X 
WY / _X 
20 rbNoh 
21 X[XCO 
22 tHbNXgbg 
23 WYc 
24 AVbhWY 
25 et[W 
26 gX 
27 fBXR 
28 bv 
29 t@N 
[sA / e 
30 |J 
31 }[‘ 
32 c@ 1
33 c@ 2
34 ^S 
35 {Tmo 
36 To 
37 }{ 
38 o 
39 ‘‘‘ 
»… 
40 Q 
41 QG 
42 XJ 
43 ebNXbNX 
44 tHN[ 
45 Jg[ 
46 SXy 
47 A_j 
48 obN 
49  
01 ««fl 
02 '¢¢I[KX‘ 
03 ACWOEOCX 
04  
05 h· 
06 hf[ 
07 O[X[uX 
08 ‰Øı 
00 AClENClEingEW[N 
11
12
 
13
AvXŒ 
14
T^E‘A 
15
„si 
16
twlGxŁ 
17
10
WOx 
si¨w›ØŁl‘x 
20 SONG BANK50 RHYTHMS
09 º˘–…Ł˜ 
18
19
AnEIG 
G^[eBi[ 
F‹æ 
MELODY
ON/OFF

— 2 —
CONTENTS
Specifications .......................................................................................................................... 2
Block Diagram......................................................................................................................... 3
Circuit Description ...................................................................................................................4
Troubleshooting ......................................................................................................................7
Major Waveforms .................................................................................................................... 8
Schematic Diagrams ............................................................................................................... 9
Printed Circuit Boards ...........................................................................................................11
Exploded View ...................................................................................................................... 13
Parts List ............................................................................................................................... 15
SPECIFICATIONS
GENERAL
Number of keys: 61
Polyphonic: 12-note
Preset tones: 100
Auto-rhythms: 50, Tempo control: 40 to 255
Accompaniment: CONCERT Chord, Fingered
Song bank: 20-tune
Tuning control: 440 Hz ±50 cents
Built-in speakers: 4 inch dia. 1 W input rating: 2 pcs
Terminals: Headphone Jack (Output impedance: 50 ohm, Output voltage: 4.6 V (rms) MAX
Power source: 2-way AC or DC source
AC: AC adapter
DC: 6D size dry batteries, Vehicle battery with DC adapter
Power consumption: 7.7 W
Dimensions(HWD): 90 ×910 ×322 mm (3-1/2 ×36-3/16 ×12-11/16 inches)
Weight: 3.9 kg (8 lbs) excluding batteries
ELECTRICAL
Current drain with 9 V DC:
No sound output 120 mA ±30%
Maximum volume 650 mA ±30%
with white keys C1 to G2 pressed in Synth-Lead 1
Volume: 9
Phone output Level (Vrms with 8 ohm load each channel):
with key E3 pressed in Synth-Lead 1 80 mV ±30%
Sound Pressure (at 10 cm away from speaker):
with key E3 pressed in Synth-Lead 1 100 dB ±10 dB
Minimum operating voltage: 6.0 V

— 3 —
CPU
MSM 6755B-06
LSI101
Keyboard
Buttons
LED
Reset IC
IC102 Oscillator X101, Q111
Q105
Power Supply Circuit
Q101 ~ Q104, D108, D109
Power Amp.
LA4598
IC101
Filter (L)
Q109
Filter (R)
Q110
Output
DC+9V IN
VC VCC AVDD DVDD LVDD
APO
CC1 ~ CC3
La ~ Lg,
Lp KO8 ~
KO11 KI0 ~ KI7
KO0 ~ KO7
BLOCK DIAGRAM

— 4 —
CIRCUIT DESCRIPTION
KEY MATRIX
KI0 KI1 KI2 KI3 KI4 KI5 KI6 KI7
KO0 C1 G#1 E2 C3 G#3 E4 C5 G#5
KO1 C#1 A1 F2 C#3 A3 F4 C#5 A5
KO2 D1 A#1 F#2 D3 A#3 F#4 D5 A#5
KO3 D#1 B1 G2 D#3 B3 G4 D#5 B5
KO4 E1 C2 G#2 E3 C4 G#4 E5 C6
KO5 F1 C#2 A2 F3 C#4 A4 F5
KO6 F#1 D2 A#2 F#3 D4 A#4 F#5
KO7 G1 D#2 B2 G3 D#4 B4 G5
KO8 0 1 2 3 4 Start/Stop Tempo
Up Volume Up
KO9 56789
Tempo
Down Volume Down Synchro/ Fill-In
K10 Tone Rhythm Song
Bank Melody On/Off
K11 Fingered CONCERT
Chord Normal Power Off
NOMENCLATURE OF KEYS
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
F3 G3 A3 B3 C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 C6
D#3
C2 D2 E2 F2 G2 A2 B2 C3 D3 E3 B6A6G6F6E6D6 C7
C#3A#2G#2
F#2D#2
C#2 A#6 G#6F#6D#6
C#6

— 5 —
+
+
AVDD
AG
AG AG AG AG
16 V 10 µ
2SC1740SQ10 K
10
10 K 10 K
C332(H)
33 K
C152 (H)
C221B (A)
10 V 22 µ
2.2 K
To main volume
From the CPU
CPU (LSI101: MSM6755B-06)
The CPU contains a sound data ROM and a DAC (Digital to Analog Convertor), and it provides left and right
channel sound waveforms in accordance with the pressed key and the selected tone.
The following table shows the pin functions of LSI101.
Pin No. Terminal In/Out Function
1 ~ 29 MA14 ~ NC2 — Not used.
30 DGND In Ground (0V) source
31 DVCC In +5V source
32, 33 XTLO, XTLI In/Out 20MHz clock input/output
34 NC3 — Not used. Connected to ground.
35 RSTB In Reset signal input
36 P24/RXD — Not used. Connected to +5V.
37 P25/TXD — Not used.
38 NMI In Power on signal input
39 APO Out APO (Auto Power Off) signal output
40 NC4 — Not used.
41 REFH Out Terminal for the internal DAC
42, 43 NC5, NC6 — Not used.
44 DAOR Out Right channel sound waveform output
45 NC7 — Not used.
46 AVdac In +5V source for the internal DAC and ADC
47 DAOL Out Left channel sound waveform output
48 REFL Out Terminal for the internal DAC and ADC
49 AGdac In Ground source for the internal DAC
50 AGadc In Ground source for the internal ADC
51 ANI — Not used. Connected to ground.
52 AVadc In +5V source for the internal ADC
53 NC8 — Not used. Connected to +5V.
54 MOD0 In Mode selection terminal
55, 56 MOD1, MOD2 In Mode selection terminal
57 KO9/P40 In Power source detection signal input
58 ~ 65 KI0/P30 ~ KI7/P37 In Terminals for key/button input signal
66 ~ 73 KO1/P50 ~ KO8/P57 Out Terminals for key scan signal
74 ~ 77 P20 ~ P23 Out Terminals for button input signal
78 NC9 — Not used.
79 LVCC In +5V source
80 ~ 82 CC1 ~ CC3 Out LED common signal output
83 ~ 87 — — Not used.
88 ~ 95 La ~ Lg, Lp Out Not used.
96 LGND In Ground (0V) source
97 ~ 100 — — Not used.
FILTER BLOCK
Since the sound signal from the CPU is a stepped waveform, the filter block is added to smooth the waveform.

— 6 —
POWER AMPLIFIER (IC101: LA4598)
The power amplifier is a two-channel amplifier with standby switch.
The following table shows the pin function of IC101.
Pin No. Terminal In/Out Function
1 Power GND In Ground (0V) source
2 Ch1 B.S. — Terminal for a bootstrap capacitor
3 Ch1 OUT Out Channel 1 output
4 VCC In +9V source
5 Ch1 N.F. In Negative feedback input
6 Ch1 IN In Channel 1 input
7 D.C. — Terminal for a decoupling capacitor
8 Pre GND In Ground (0V) source
9 Stand by In Power control signal input. 0 V: Off, +9 V: On
10 Ch2 IN In Channel 2 input
11 Ch2 N.F. In Negative feedback input
12 Ch2 OUT Out Channel 2 output
13 Ch2 B.S. — Terminal for a bootstrap capacitor
14 NC — Not used
LED DRIVING
CPU
LSI01
MSM6755B
La~Lg, Lp
CC1~CC3
LVDD
Q106~Q108
LED Driver
LG


— 7 —
INITIAL 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.
CPU
MSM 6755B-06
LSI101
RESET
Reset IC
RE5VA35A
IC102
VDD Battery Set
TROUBLESHOOTING
Nature of Trouble Faulty Block Cause/Remedy
No power Power supply circuit Faulty IC101. Replace IC101.
Faulty D106 ~ D109. Replace D106 ~
D109.
Faulty Q101 ~ Q104. Replace Q101 ~
Q104.
Power switch Poor contact. Clean the contacts.
Power jack (J101) Open J101 or poor soldering. Replace
J101 or resolder.
No sound at all Power Amp (IC101: LA4596) Open or shorted IC101. Replace IC101.
CPU (LSI101: MSM6755B-06) Faulty LSI101. Replace LSI101.
Oscillator Faulty Q111. Replace Q111.
Open X101. Replace X101.
Certain keys or switches
do not function Key and switch matrix Open circuit on KO or KI line. Replace keyboard PCB assembly.
CPU (LSI101: MSM6755B-06) Faulty LSI101. Replace LSI101.
A certain key or switch
does not function Key and switch matrix Dust on the contact.

— 8 —
0.1 s
CH1
CH1 5V BWL
20 µs
CH1
BWL
CH1 1V
10 µs
CH1
CH2
CH2 BWL
CH1 5V 5V
1ms
CH2
CH1
BWL
CH1 1V 1V
CH2
1ms
CH1
CH2
BWL
CH1 1V CH2 1V
1ms
CH1
CH2
BWL
CH1 1V 1V
CH2
1RESET signal
IC102 pin 1 2Main clock pulse MSM6755B-06 pin 32
3Key scan signal KO10
MSM6755B-06 pin 76
4Key scan signal KO11
MSM6755B-06 pin 77
5Sound signal output (L-ch)
MSM6755B-06 pin 47
6Sound signal output (L-ch)
Q109 2SC1740SQ Emitter
7Sound signal output (R-ch)
MSM6755B-06 pin 45
8Sound signal output (R-ch)
Q110 2SC1740SQ Emitter
9Sound signal output (R-ch)
LA4598 pin 3
0Sound signal output (L-ch)
LA4598 pin 12
Tone: Flute Ensemble (58)
Key: A3
Volume: 7
12
5
6
9
0
3
4
7
8
MAJOR WAVEFORMS

— 9 —
SCHEMATIC DIAGRAMS
Main PCB KDM440-MA1M
10
96
8
75
3
4
2
1
Notes:
1. All capacitance values are indicated in "µF" (p=10-6 µF)
2. All resistance values are indicated in "Ω" (k=103 Ω, M=106 Ω).

— 10 —
Keyboard PCBs KDM6111K-KY1M/KY2M
Notes:
1. All capacitance values are indicated in "µF" (p=10-6 µF)
2. All resistance values are indicated in "Ω" (k=103 Ω, M=106 Ω).

— 11 —
9657 1081234
PRINTED CIRCUIT BOARDS
Main PCB KDM440-MA1M
Top View
Console PCB KDM6111K-KY1M
Top View
Console PCB KDM6111K-KY2M
Top View

— 12 —
Main PCB KDM440-MA1M
Bottom View
Console PCB KDM6111K-KY1M
Bottom View
Bottom View
Console PCB KDM6111K-KY2M

8
9
10
11
4
2
1
7
6
4
16 15
16
13
15
12 14
5
3

R-1
R-2
R-3
R-4 R-5
EXPLODED VIEW
— 13 —

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 with-
out 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.
PARTS LIST
CTK-480

FOB Japan
N Item Code No. Parts Name Specification Q N.R.Yen R
Unit Price
MAIN PCB ASSEMBLY
IC101 2114 2891 Monolithic IC LA4598 1 A
IC102 2105 5922 IC RE5VL40AA-TZ 1 A
LSI101 2012 3486 LSI, CPU MSM6755B-06 1 A
Q101 2251 0469 Transistor 2SB1237Q 1 B
Q102 2220 1387 Transistor 2SC1740Q 1 B
Q103/104 2253 0448 Transistor 2SD1858Q 2 B
Q105 2200 2449 Transistor 2SA933SQ 1 B
Q106 - 111 2220 1387 Transistor 2SC1740Q 6 B
D101 2360 1729 Zener diode MTZJ5.1A 1B
D103 2390 2828 Diode RB441Q-40T 1 B
D105 2390 2828 Diode RB441Q-40T 1 B
D106 2390 2408 Zener diode 1FW143N 1B
D107 2390 2828 Diode RB441Q-40T 1 B
D108 2360 2002 Zener diode MTZJ5.6BT 1B
D109 2360 2002 Zener diode MTZJ5.6BT 1B
D110 - 129 2390 2828 Diode RB441Q-40T 20 B
D130 2390 2828 Diode RB441Q-40T 1 B
LED101 2370 1106 LED MPR3338S-B99 1 B
LED102 2370 1309 LED LB603VF1 1 B
X101 2590 1526 Ceramic oscillator EFO-EN2005C4 1B
J101 3501 7046 Power jack HEC2305-01-330 1 A
J102 3612 0665 Phones jack YKB21-5006 1 C
CONSOLE PCB ASSEMBLY
D701 - 725 2301 0101 Diode 1SS2473 25 B
D731 - 766 2301 0101 Diode 1SS2473 36 B
MECHANICAL PARTS
1 6909 5890 Slide contact CSB-12D 1B
2 6925 1560 Key contact rubber, 6-contact M340418-1 1B
3 6925 1630 Key contact rubber, 14-contact M340417-1 1B
4 3831 0770 Speaker S10JA13A 2B
5 6925 1260 PCB ass'y, MA1M 6925 1260 M140403*1 1B
6 6925 1890 Battery cover M340485*1 1 B
7 6921 5030 Slide knob M311859-1 1 B
8 6922 2720 White key set, 7-Key M312118*1 4 A
9 6922 2730 White key set, 8-Key M312118*2 1 A
10 6922 2750 Black key set, 5-Key M111726-2 1 A
11 6922 2740 Black key set, 10-Key M111726-1 2 A
12 6922 4000 Key contact rubber, 31-contact M111765-1 1 B
13 6922 3990 Key contact rubber, 30-contact M111764-1 1 B
14 6925 1310 PCB ass'y, KY M140402*1 1B
15 6925 1600 Plastic foot M440346-1 2 B
16 6925 1620 Rubber foot M440366-1 2 B
— 15 —

MA0600761A