Roland JC-40 Operating and maintenance manual

SERVICE NOTES
Issued by RJA
Copyright © 2015 Roland Corporation
All rights reserved. No part of this publication may be reproduced in any form without the written permission
of Roland Corporation.
CC-KWS17057004E0
JC-40Nov. 2015
Table of Contents
Cautionary Notes ..............................................................2
Specifications .....................................................................3
Location of Controls .........................................................4
Exploded View (Cabinet).................................................5
Plain View (Cabinet).........................................................6
Plain View (Cabinet) Parts List .......................................7
Exploded View (Chassis) .................................................8
Exploded View (Chassis) Parts List................................9
Plain View (Chassis) .......................................................10
Important Notes When Binding Wiring ......................11
Wiring Diagram/Block Diagram..................................12
Parts List...........................................................................14
Verifying the Version......................................................16
Test Mode .........................................................................16
Circuit Board (Main, Jack, Volume, PS, Inlet Board) .18
Circuit Diagram (Main Board: 1/4)..............................20
Circuit Diagram (Main Board: 2/4)..............................22
Circuit Diagram (Main Board: 3/4)..............................24
Circuit Diagram (Main Board: 4/4)..............................26
Circuit Diagram (Jack Board) ........................................28
Circuit Diagram (Volume Board) .................................30
Circuit Diagram (PS Board) ...........................................31
Circuit Diagram (Inlet Board) .......................................31

2
Nov. 2015 JC-40
Cautionary Notes
Before beginning the procedure, please read
through this document. The matters described may
differ according to the model.
No User Data
This product cannot save user data. Backing up user data during servicing is
not required.
Part Replacement
When replacing components near the power-supply circuit or a heat-
generating circuit (such as a circuit provided with a heat sink or including a
cement resistor), carry out the procedure according to the instructions with
respect to the part number, direction, and attachment position (mounting so as
to leave an air gap between the component and the circuit board, etc.).
Parts List
A component whose part code is ******** will not be supplied as a service part
because one of the following reasons applies.
• Because it is supplied as an assembled part (under a different part code).
• Because a number of circuit boards are grouped together and supplied as
a single circuit board (under a different part code).
• Because supply is prohibited due to copyright restrictions.
• Because reissuance is restricted.
• Because the part is made to order (at current market price).
• Because it is carried in electronic data on the Roland web site.
• Because it is a package or an accessory irrelevant to the function
maintenance of the main body.
• Because it can be replaced with an article on the market. (battery or etc.)
Circuit Diagram
In the circuit diagram, “NIU” is an abbreviation for “Not in Use,” and
“UnPop” is an abbreviation for “Unpopulated.” They both mean non-mounted
components. The circuit board and circuit board diagram show silk-screened
indications, but no components are mounted.

3
JC-40Nov. 2015
Specifications
Roland JC-40: Guitar Amplifier
Rated Power Output
40 W
Nominal Input Level
INPUT L/MONO, R jacks: -10 dBu (1 M ohm)
EFFECT RETURN L/MONO, R jacks: -10 dBu (22 k ohms)
EFFECT RETURN L/MONO only: -10 dBu (11 k ohms)
Speakers
25 cm (10 inches) x 2
Controls
POWER switch
BRI (Bright) Switch
VOLUME knob
TREBLE knob
MIDDLE knob
BASS knob
DISTORTION knob
REVERB knob
SPEED knob
DEPTH knob
VIB/CHORUS switch
EFFECT LOOP switch
Indicator
POWER
Connectors
INPUT L/MONO, R jacks: 1/4-inch phone type
LINE OUT L/MONO, R jacks: 1/4-inch phone type
PHONES jack: Stereo 1/4-inch TRS phone type
FOOT SWITCH (CHORUS VIBRATO, REVERB, DISTORTION) jacks: 1/4-inch
phone type
EFFECT LOOP SEND jack: 1/4-inch phone type
EFFECT LOOP RETURN L/MONO, R jacks: 1/4-inch phone type
AC IN jack
Power Consumption
43 W
Dimensions
592 (W) x 251 (D) x 436 (H) mm
23-5/16 (W) x 9-15/16 (D) x 17-3/16 (H) inches
Weight
15.8 kg
34 lbs 14 oz
Accessories
Owner's manual (#5100046052)
Power cord (#5100029165, #5100012292, #00894378, #03450323, #5100013648,
#00907001, #00894389, #5100013842)
Options (sold separately)
Footswitch (BOSS FS-5L, FS-6, FS-7)
* 0 dBu = 0.775 Vrms
* Printed matters will not be supplied after the end of the production. Then,
download the electronic file from the Roland web site.
* In the interest of product improvement, the specifications and/or appearance of
this unit are subject to change without prior notice.

4
Nov. 2015 JC-40
Location of Controls
fig.panel.eps
6 59 4 127
10 10
9
11
12
3 3 38
88
8
No. Part Code Part Name Description Q’ty
1 02897801 SEESAW SWITCH SDDJE13200 94V-0 1
5100046595 POWER SW ESCUTCHEON 1
5100046598 POWER SW CUSHION 2
2 5100048310 LED L-7113-CW914(S) 1
5100046599 LED SPACER LEH5-6T 1
5100046591 LED ESCUTCHEON 1
3 22485314 JC-KNOB 248-314(22485314R0) 9
4 5100042592 SWITCH S171EV114GFS2AN17 1
* This unit includes the following parts.
******** NUT attached to Switch 1
******** WASHER attached to Switch 1
******** SPACER attached to Switch 1
5 5100033433 ROTARY POTENTIOMETER R0923NOCV1B103FE00A1 2
* This unit includes the following parts.
******** VR NUT attached to VR 2
******** VR WASHER attached to VR 2
6 5100037963 ROTARY POTENTIOMETER R0923NOCH1B103FE00A1 6
* This unit includes the following parts.
******** VR NUT attached to VR 6
******** VR WASHER attached to VR 6
7 00125612 KEYTOP (BLK/GRY) 1
01348745 SWITCH(PUSH) SPUP192700(400-11034-01-00) 1
8 5100046593 JACK SPACER 11
9 5100024419 6.5MM JACK PJ-644C-04-EP(610-11020-01-00 9
* This unit includes the following parts.
******** JACK NUT attached to Jack 9
******** JACK WASHER attached to Jack 9
10 5100031944 6.5MM JACK PJ-644C-EP 2
* This unit includes the following parts.
******** JACK NUT attached to Jack 2
******** JACK WASHER attached to Jack 2
11 04459978 SLIDE SWITCH SV70050F-0202-10T-NN 1
12 5100033643 AC INLET(610-11017-08-00) M1908-B W/ CCC MARK 1

5
JC-40Nov. 2015
Exploded View (Cabinet)
fig.bunkaizu-cabinet.eps
4
1
3
2
6
5
5
7
8
9
Refer to Chassis
View 6
View 7
View 2
View 1
View 5
View 3
View 4
No. Part Code Part Name Description Q’ty
5100042788 CABINET ASSY W/O SPEAKER 1
* This unit includes the following parts.
1******** CABINET
2******** NET BOARD ASSY 1
3 22510402 BADGE G.AMP 61 1
4 22310207 HANDLE (H40) 231-207 W/ESCUCHEON (2 HOLES) 1
5 22340202 PROTECTION CORNER 8
6 5100046034 RUBBER FOOT D25*T12 BLK 4
9******** BACK BOARD 1
7 5100046048 SPEAKER W1004-057A 2
8 5100046047 LABEL SPEAKER MAGNET 2

6
Nov. 2015 JC-40
Plain View (Cabinet)
fig.bunkaizu-cabinet-H.eps
a
d
e
c c
b
c
c
f f
g
g
View 1 View 2
View 3 View 4 View 5
View 6 View 7

7
JC-40Nov. 2015
Plain View (Cabinet) Parts List
View 1
View 2
View 3, 4
View 5
View 6
View 7
No. Part Code Part Name Description Q’ty
a 40010489 SCREW M5X30 OVAL FE BZC 4
c 40010601 SCREW M5X35 ORIGINAL TRUSS MACHINE FE BZC 6
No. Part Code Part Name Description Q’ty
b 5100046058 SCREW 3X14 OVAL TAPPING A ED-BLK 2
No. Part Code Part Name Description Q’ty
c 40010601 SCREW M5X35 ORIGINAL TRUSS MACHINE FE BZC 2
No. Part Code Part Name Description Q’ty
d 40010689 SCREW 4X25 TRUSS TAPPING A FE BZC 4
No. Part Code Part Name Description Q’ty
e 40010678 SCREW 4X20 TRUSS TAPPING A FE BZC 6
No. Part Code Part Name Description Q’ty
f 40560756 FLANGE NUT M4 BZC 8
g 40560756 FLANGE NUT M4 BZC 7
5100044181 PLAIN WASHER 4.2X10X1 BZC 7
5100046055 SPRING WASHER 4.4X6.5X1 BZC 7

8
Nov. 2015 JC-40
Exploded View (Chassis)
fig.bunkaizu-chassis.eps
2
6
19
18
16
20
17
9
22
14 15
4
5
3
1
7
10 11
12 13
14
21
8
8
g
h
e
i
f
j
k
h
g
c
c
d
d
a
b
8
23
View 9
View 8

9
JC-40Nov. 2015
Exploded View (Chassis) Parts List
No. Part Code Part Name Description Q’ty
1 00125612 KEYTOP (BLK/GRY) 1
2 22485314 JC-KNOB 248-314(22485314R0) 9
3 5100046591 LED ESCUTCHEON 1
4 5100046595 POWER SW ESCUTCHEON 1
5 5100046598 POWER SW CUSHION 2
6 02897801 SEESAW SWITCH SDDJE13200 94V-0 1
7 5100046042 CHASSIS 1
8 5100039123 POWER AMP TDA2050L-TB5-T 2
9 5100046590 HEATSINK 2
5100042776 MAIN SHEET ASSY 1
* This unit includes the following parts.
10 ******** MAIN BOARD 1
11 ******** JACK BOARD 1
12 ******** VOLUME BOARD 1
13 ******** PS BOARD 1
18 ******** INLET BOARD 1
14 5100046593 JACK SPACER 11
15 22150580 STANDOFF M3-L5.5-H7 6
16 5100016080 POWER TRANS(461-11035-01-00) PT-AP018 100/117V for low voltage 1
5100016081 POWER TRANSFORMER PT-AP018 230/240V for high voltage 1
17 5100046592 TRANS PLATE 2
19 5100033643 AC INLET(610-11017-08-00) M1908-B W/ CCC MARK 1
20 5100046602 ACETATE TAPE #156A 35X25XT0.25 2
21 5100048346 ACETATE TAPE NITTO #156A BLACK W20MM 30M -
22 40342901 SILICONE GREASE G-746 200G -
23 40122445 ADHESIVE CEMEDINE SUPER-X NO.8008 170G/135ML -
a 40011767 FLANGE HEX NUT M4 FE ZC 2
b 40230023 SPRING WASHER M4 ZC 2
c 40017934 SCREW M3X6 PAN MACHINE W/SW+PW(L) FE ZC 6
d 40013078 SCREW M3X10 PAN MACHINE W/SW FE ZC 2
e******** VR NUT attached to VR 8
f******** VR WASHER attached to VR 8
g******** JACK NUT attached to Jack 11
h******** JACK WASHER attached to Jack 11
i******** NUT attached to Switch 1
j******** WASHER attached to Switch 1
k******** SPACER attached to Switch 1

10
Nov. 2015 JC-40
Plain View (Chassis)
fig.bunkaizu-chassis-H.eps
View 8
View 9
c
e
c
cc
a ab
dd
25
View 8
View 9
No. Part Code Part Name Description Q’ty
a 40012945 SCREW M3X6 PAN MACHINE W/SW+PW BZC 2
b 40011112 SCREW 3X10 BINDING TAPTITE B BZC 2
No. Part Code Part Name Description Q’ty
25 40013812 CAUTION SEAL IEC #142 1
c 40017934 SCREW M3X6 PAN MACHINE W/SW+PW(L) FE ZC 15
d 22150580 STANDOFF M3-L5.5-H7 6
e 40011889 EXTERNAL TOOTH WASHER M4 FECM 1
40011767 FLANGE HEX NUT M4 FE ZC 1