SKW-204
SERVICE MANUAL
SERVICE MANUAL
POWERED SUBWOOFER
Black, Silver and Yellow models
MODEL
SKW-204(B)/(S)/(Y)
Ref. No. 3946
052006
120V AC, 60Hz
230-240V AC, 50Hz
230-240V AC, 50Hz
B MDC
B MPP
S MPP
230-240V AC, 50Hz
120/220-240V AC, 50/60Hz
120/220-240V AC, 50/60Hz
S MPA
S MWT
Y MWT
SAFETY-RELATED COMPONENT
WARNING!!
COMPONENTS IDENTIFIED BY MARK
ON THE
SCHEMATIC DIAGRAM AND IN THE PARTS LIST ARE
CRITICAL FOR RISK OF FIRE AND ELECTRIC SHOCK.
REPLACE THESE COMPONENTS WITH ONKYO
PARTS WHOSE PART NUMBERS APPEAR AS SHOWN
IN THIS MANUAL.
MAKE LEAKAGE-CURRENT OR RESISTANCE
MEASUREMENTS TO DETERMINE THAT EXPOSED
PARTS ARE ACCEPTABLY INSULATED FROM THE
SUPPLY CIRCUIT BEFORE RETURNING THE
APPLIANCE TO THE CUSTOMER.
SKW-204
EXPLODED VIEWS-1
AMPLIFIER SECTION
SKW-204
SP12
x 4 pcs.
A05a
x 2 pcs.
A05
x 4 pcs.
A08
x 2 pcs.
SP11
x 10 pcs.
A05
x 2 pcs.
A05
x 2 pcs.
A05
x 5 pcs.
A103
A103
A102
P901
SP13
x 2 pcs.
U03
A11
A01
U01
A07
A07
A101
A02
A02
U06
U05
U04
U02
A05
Q515
Q516
Q541
F901
T901
A04
A03
F901C
S901
A06
F902
Refer to "EXPLODED VIEWS-2"
<Note>
U04 (VOLTAGE SELECTOR PC BOARD) : MWT type only.
<Note>
F901C (LABEL) : MPP/MPA type only.
Part No. (SN) ---> Refer to
"PRINTED CIRCUIT BOARD PARTS LIST".
SKW-204
EXPLODED VIEWS-2
SPEAKER SECTION
SKW-204
SP07a / b
SP09a - c
SP01a - c
SP04
x 6 pcs.
SP02
x 4 pcs.
SP04
x 4 pcs.
SP03
x 4 pcs.
SP08
SP05a / b
SP06
SP11
x 2 pcs.
SKW-204
SCHEMATIC DIAGRAM
SKW-204
A
1
2
3
4
5
B
C
DE
FG
H
P906B
P908B
P906A
P906A
P908A
P905B
P905B
P907A
P905A
P907A
T901
NPT-1539DQ
01
02
05
06
J317
FOR SKW-204AMP
J316
FOR
SKW-540AMP
S902
S101
P301A
P301B
Q303(1/2)
NJM4558LD
3
8
2
4
1
Q302(1/2)
NJM4558LD
3
8
2
4
1
E801
Q302(2/2)
NJM4558LD
4
8
5
6
7
Q303(2/2)
NJM4558LD
4
8
5
6
7
Q301(2/2)
NJM4558LD
4
8
5
6
7
Q301(1/2)
NJM4558LD
3
2
1
8
4
Q602
KRC103M
Q606
KRA103M
P301
R651
12K
(1/2W)
R951
3.3K
POWER NEED TO CONFIRM
(2W)
R952
3.3K (2W)
R901
820 (1W)
R902
820(1W)
0
1
-0.6
1.6V
-1.6
-1
0
0.05
0.6
5.0
5.6
D901
D3SBA20
R544
100B
R528
390
(1/2W)
R628
330K
R629
NC
R701
NC
R904
1K
(1/2W)
R903
10K
R609
39K
R611
820K
R610
560K
R616
100K
R617
1K
R621
1K
R615
22K
R612
39K
R614
120K
R613
470K
R619
22K
R620
100K
R624
100K
R623
100K
R627
680K
R622
10K
R626
2.2M
R625
180K
S901
S901
P901
P901
F901
5A/125V
F902
1.6A/250V
F901
1.6A/250V
T901
NPT-1539P
P903B
P903B
J903A
P632A
RED
GREEN
D601
MTZJ2.7B
D602
MTZJ2.7B
D501
MTZJ5.6B
D952
MTZJ15C
D951
MTZJ15C
D904
MTZJ5.6B
Q516
2SA1987-O/R
Q519
2SA965-Y
Q517
2SA933S-S
Q507
2SA949-Y
Q505
2SA949-Y
Q509
2SA949-Y
Q514
2SA1930
Q604
2SA933S
Q605
2SA933S
Q607
2SA933S
Q541
2SC3423
Q506
2SC2229-Y
Q510
2SC2229-Y
Q503
2SC2240-BL
Q515 2SC5359-O/R
Q513
2SC5171
Q518
2SC2235-Y
Q502
2SC2240-BL
Q501
2SC2240-BL
Q609
NC
Q603
2SC1740S-S
Q608
2SC1740S-S
P906B
P902A
P902A
JL535A/B
P531
P501B
P633
P631
D651
1SS133
D603
1SS133
D606
1SS133
D903
RL1N4003
or GP104003E
D902
RL1N4003
or GP104003E
D605
1SS133
R302
20K
R101(2/2)
20K
R101
20K
C301
C303
NC
C955
223J
C316 124
C313 124
C315
334J
C312
334J
C506
070
C502
NC
C514
101
C520
224
C519
224
C505
020
C503
224J
C950
104/50
C903
104J/100
C904
104J/100
C311
100/25
C302
47/50
C314
47/16
C527
1/50
C501
47/50
C517
10/50
C528
10/50
C526
10/50
C504
220/16
C951
220/16
C952
220/16
C909
22/50
C601
10/50
C603
470/16
C602
10/50
C604
33/35
C906
5600/71
C905
5600/71
R317
2.2K
R306
47K
R301
1K
R311
100K
R313
3.3K
R312
100K
R314
3.3K
R315
3.3K
R307
220*
R305
22K*
R303
47K
R304
2.2K*
R321
1K
R320
10K
R316
10K
R319
100K
R531
0.22
(5W)
R533
3.3
(1W)
R508
47
(1/4W)
R511
82
(1/4W)
R512
68
(1/4W)
R514
82 (1/4W)
R513
82
(1/4W)
R516
12K
R515
12K
R502
47K
R510
100K
R543
180
R526
82
(1/2W)
R517
3.3K
R541
820
R542
150
R505
1K
(1/4W)
R506
1K
(1/4W)
R507
33K
R527
270
R509
1K
R504
2.2K
R503
5.6K
R522
220
R521
220
R501
1K
R603
150K
R601
5.6K
R605
22
R602
100K
R604
180
FOR SKW-204AMP
NAAF-8830
PHASE SWITCH
OFF
ON
MWT
MPP/MPA
NAPS-8831
NASW-8832
NASW-8833
NAPS-8831
NASW-8833
FOR SKW-204AMP
PHASE SWITCH AND FREQUENCY ADJUST.
P906A
P907A
S901
P901
F901
5A/125V
T901
NPT-1539D
P903B
P906B
P902A
MDC
NASW-8833
NAPS-8831
NAAF-8829
224
(PP/PA/WT)
NC
NC
NC
NC
NC
+5.6V
AGAINST FIRE HAZARD, REPLACE
V
A
FOR CONTINUED PROTECTION
AND RATING INDICATED.
ONLY WITH FUSE OF SAME TYPE
CAUTION
ATTENTION
ET CALIBRATION COMME INDIQUE.
D'INCENDIE, REMPLACER UNIQUEMENT
PERMANENTE CONTRE LES RISQUES
AFIN D'ASSURER UNE PROTECTION
PAR UN FUSIBLE DE MEME TYPE
V
A
E LENT.POUR UNE PROTECTION PERMANENTE,N'UTILISER
INDIQUE LA QU LE PRESENT SYMBOL EST APPOSE.
QUE DES FUSIBLES DE MEME TYPE. CE DARNIER EST
CE SYMBOLE INDIQUE QUE LE FUSIBLE UTLISE EST
FOR CONTINUED PROTECTION AGAINST FIRE
RATING REFER TO THE MARKING ADJACENT TO THE SYMBOL.
HAZARD,REPLACE WITH SAME TYPE FUSE. FOR FUSE
THIS SYMBOL LOCATED NEAR THE FUSE INDICATES
THAT THE FUSE USED IS SLOW OPERATING TYPE
THE COMPONENTS IDENTIFIED BY MARK
ARE CRITICAL FOR SAFETY
REPLACE ONLY WITH PART NUMBER SPECIFIED.
VOLTAGE (MEASURED WITH VOLTMETER)
IS DC VOLTAGE.(NO INPUT SIGNAL).
ALL PNP TRANSISTORS ARE EQUIVALENT TO 2SA1015-GR UNLESS OTHERWISE NOTED.
ALL NPN TRANSISTORS ARE EQUIVALENT TO 2SC1815-GR UNLESS OTHERWISE NOTED.
ALL DIODES ARE EQUIVALENT TO 1SS133 UNLESS OTHERWISE NOTED.
ELECTROLYTIC CAPACITORS (
) ARE IN uF/WV.
ALL CAPACITORS ARE IN pF/50WV UNLESS OTHERWISE NOTED.
EX) 030- 3pF 330- 33pF 331- 330pF 333- 0.033uF
ALL RESISTORS ARE IN OHMS 1/4WATTS UNLESS OTHERWISE NOTED.
THE THICK LINES ON PC BOARD ARE THE PRINTING SIDE OF THE PARTS.
EX)
PRINTING SIDE
CIRCUIT IS SUBJECT TO CHANGE FOR IMPROVEMENT.
!
NOTE
POWER SWITCH
PC BOARD
U05
POWER
TRANSFORMER
PC BOARD
U03
MAIN PC BOARD
U01
LINE INPUT
OUTPUT
LEVEL
POWER
SWITCH
SPEAKER
LED
MPP/MPA
ADJUST.
IDLING
<Note>
NC : No mount of parts.
Hi
Hi
Lo
VOLTAGE
SELECTOR
PC BOARD
U04
MWT
Lo
MWT
FREQUENCY ADJUSTMENT
PC BOARD
U02
POWER
SWITCH
MDC
FREQ.
SKW-204
SCHEMATIC DIAGRAM
SKW-204
A
1
2
3
4
5
B
C
DE
FG
H
P906B
P908B
P906A
P906A
P908A
P905B
P905B
P907A
P905A
P907A
T901
NPT-1539DQ
01
02
05
06
J317
FOR SKW-204AMP
J316
FOR
SKW-540AMP
S902
S101
P301A
P301B
Q303(1/2)
NJM4558LD
3
8
2
4
1
Q302(1/2)
NJM4558LD
3
8
2
4
1
E801
Q302(2/2)
NJM4558LD
4
8
5
6
7
Q303(2/2)
NJM4558LD
4
8
5
6
7
Q301(2/2)
NJM4558LD
4
8
5
6
7
Q301(1/2)
NJM4558LD
3
2
1
8
4
Q602
KRC103M
Q606
KRA103M
P301
R651
12K
(1/2W)
R951
3.3K
POWER NEED TO CONFIRM
(2W)
R952
3.3K (2W)
R901
820 (1W)
R902
820(1W)
0
1
-0.6
1.6V
-1.6
-1
0
0.05
0.6
5.0
5.6
D901
D3SBA20
R544
100B
R528
390
(1/2W)
R628
330K
R629
NC
R701
NC
R904
1K
(1/2W)
R903
10K
R609
39K
R611
820K
R610
560K
R616
100K
R617
1K
R621
1K
R615
22K
R612
39K
R614
120K
R613
470K
R619
22K
R620
100K
R624
100K
R623
100K
R627
680K
R622
10K
R626
2.2M
R625
180K
S901
S901
P901
P901
F901
5A/125V
F902
1.6A/250V
F901
1.6A/250V
T901
NPT-1539P
P903B
P903B
J903A
P632A
RED
GREEN
D601
MTZJ2.7B
D602
MTZJ2.7B
D501
MTZJ5.6B
D952
MTZJ15C
D951
MTZJ15C
D904
MTZJ5.6B
Q516
2SA1987-O/R
Q519
2SA965-Y
Q517
2SA933S-S
Q507
2SA949-Y
Q505
2SA949-Y
Q509
2SA949-Y
Q514
2SA1930
Q604
2SA933S
Q605
2SA933S
Q607
2SA933S
Q541
2SC3423
Q506
2SC2229-Y
Q510
2SC2229-Y
Q503
2SC2240-BL
Q515 2SC5359-O/R
Q513
2SC5171
Q518
2SC2235-Y
Q502
2SC2240-BL
Q501
2SC2240-BL
Q609
NC
Q603
2SC1740S-S
Q608
2SC1740S-S
P906B
P902A
P902A
JL535A/B
P531
P501B
P633
P631
D651
1SS133
D603
1SS133
D606
1SS133
D903
RL1N4003
or GP104003E
D902
RL1N4003
or GP104003E
D605
1SS133
R302
20K
R101(2/2)
20K
R101
20K
C301
C303
NC
C955
223J
C316 124
C313 124
C315
334J
C312
334J
C506
070
C502
NC
C514
101
C520
224
C519
224
C505
020
C503
224J
C950
104/50
C903
104J/100
C904
104J/100
C311
100/25
C302
47/50
C314
47/16
C527
1/50
C501
47/50
C517
10/50
C528
10/50
C526
10/50
C504
220/16
C951
220/16
C952
220/16
C909
22/50
C601
10/50
C603
470/16
C602
10/50
C604
33/35
C906
5600/71
C905
5600/71
R317
2.2K
R306
47K
R301
1K
R311
100K
R313
3.3K
R312
100K
R314
3.3K
R315
3.3K
R307
220*
R305
22K*
R303
47K
R304
2.2K*
R321
1K
R320
10K
R316
10K
R319
100K
R531
0.22
(5W)
R533
3.3
(1W)
R508
47
(1/4W)
R511
82
(1/4W)
R512
68
(1/4W)
R514
82 (1/4W)
R513
82
(1/4W)
R516
12K
R515
12K
R502
47K
R510
100K
R543
180
R526
82
(1/2W)
R517
3.3K
R541
820
R542
150
R505
1K
(1/4W)
R506
1K
(1/4W)
R507
33K
R527
270
R509
1K
R504
2.2K
R503
5.6K
R522
220
R521
220
R501
1K
R603
150K
R601
5.6K
R605
22
R602
100K
R604
180
FOR SKW-204AMP
NAAF-8830
PHASE SWITCH
OFF
ON
MWT
MPP/MPA
NAPS-8831
NASW-8832
NASW-8833
NAPS-8831
NASW-8833
FOR SKW-204AMP
PHASE SWITCH AND FREQUENCY ADJUST.
P906A
P907A
S901
P901
F901
5A/125V
T901
NPT-1539D
P903B
P906B
P902A
MDC
NASW-8833
NAPS-8831
NAAF-8829
224
(PP/PA/WT)
NC
NC
NC
NC
NC
+5.6V
AGAINST FIRE HAZARD, REPLACE
V
A
FOR CONTINUED PROTECTION
AND RATING INDICATED.
ONLY WITH FUSE OF SAME TYPE
CAUTION
ATTENTION
ET CALIBRATION COMME INDIQUE.
D'INCENDIE, REMPLACER UNIQUEMENT
PERMANENTE CONTRE LES RISQUES
AFIN D'ASSURER UNE PROTECTION
PAR UN FUSIBLE DE MEME TYPE
V
A
E LENT.POUR UNE PROTECTION PERMANENTE,N'UTILISER
INDIQUE LA QU LE PRESENT SYMBOL EST APPOSE.
QUE DES FUSIBLES DE MEME TYPE. CE DARNIER EST
CE SYMBOLE INDIQUE QUE LE FUSIBLE UTLISE EST
FOR CONTINUED PROTECTION AGAINST FIRE
RATING REFER TO THE MARKING ADJACENT TO THE SYMBOL.
HAZARD,REPLACE WITH SAME TYPE FUSE. FOR FUSE
THIS SYMBOL LOCATED NEAR THE FUSE INDICATES
THAT THE FUSE USED IS SLOW OPERATING TYPE
THE COMPONENTS IDENTIFIED BY MARK
ARE CRITICAL FOR SAFETY
REPLACE ONLY WITH PART NUMBER SPECIFIED.
VOLTAGE (MEASURED WITH VOLTMETER)
IS DC VOLTAGE.(NO INPUT SIGNAL).
ALL PNP TRANSISTORS ARE EQUIVALENT TO 2SA1015-GR UNLESS OTHERWISE NOTED.
ALL NPN TRANSISTORS ARE EQUIVALENT TO 2SC1815-GR UNLESS OTHERWISE NOTED.
ALL DIODES ARE EQUIVALENT TO 1SS133 UNLESS OTHERWISE NOTED.
ELECTROLYTIC CAPACITORS (
) ARE IN uF/WV.
ALL CAPACITORS ARE IN pF/50WV UNLESS OTHERWISE NOTED.
EX) 030- 3pF 330- 33pF 331- 330pF 333- 0.033uF
ALL RESISTORS ARE IN OHMS 1/4WATTS UNLESS OTHERWISE NOTED.
THE THICK LINES ON PC BOARD ARE THE PRINTING SIDE OF THE PARTS.
EX)
PRINTING SIDE
CIRCUIT IS SUBJECT TO CHANGE FOR IMPROVEMENT.
!
NOTE
POWER SWITCH
PC BOARD
U05
POWER
TRANSFORMER
PC BOARD
U03
MAIN PC BOARD
U01
LINE INPUT
OUTPUT
LEVEL
POWER
SWITCH
SPEAKER
LED
MPP/MPA
ADJUST.
IDLING
<Note>
NC : No mount of parts.
Hi
Hi
Lo
VOLTAGE
SELECTOR
PC BOARD
U04
MWT
Lo
MWT
FREQUENCY ADJUSTMENT
PC BOARD
U02
POWER
SWITCH
MDC
FREQ.