Roland BOSS RT-20 Operating and maintenance manual

SERVICE NOTES
Issued by RJA
Copyright © 2006 ROLAND CORPORATION
All rights reserved. No part of this publication may be reproduced in any form without the written permission
of ROLAND CORPORATION.
Printed in Japan (0500) (SC-KWS)17058357E0
Dec. 2005 RT-20
Table of Contents
Cautionary Notes ..............................................................2
Specifications .....................................................................3
Location of Controls .........................................................4
Location of Controls Parts List........................................5
Exploded View (1).............................................................6
Exploded View (1) Parts List...........................................6
Exploded View (2).............................................................7
Exploded View (2) Parts List...........................................7
Exploded View (3).............................................................8
Exploded View (3) Parts List...........................................8
Exploded View (4).............................................................9
Exploded View (4) Parts List...........................................9
Parts List ...........................................................................10
Checking the Version Number......................................13
About Updating...............................................................13
Test Mode .........................................................................13
Block Diagram .................................................................20
Circuit Board (JACK BOARD).......................................22
Circuit Board (PANEL BOARD) ...................................23
Circuit Diagram (JACK BOARD)..................................24
Circuit Diagram (PANEL BOARD) ..............................26

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Dec. 2005 RT-20
Cautionary Notes
Before beginning the procedure, please read through this document.
No User Data
This product cannot save user data. Backing up user data during servicing is
not required.
Parts List
A component whose part code is ******** cannot 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).
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.).
Circuit Diagram
In the circuit diagram, ‘NIU’ is an abbreviation for ‘NOT IN USE’.
The circuit board and circuit-board diagram show silkscreened indications, but
no components are mounted.

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Dec. 2005 RT-20
Specifications
RT-20: Rotary Sound Processor
Nominal Input Level
-20 dBu
Input Impedance
1 MΩ
Output Impedance
1 kΩ
Recommended Load Impedance
10 kΩor greater
Display
VIRTUAL ROTOR
Controls
EFFECT ON/OFF pedal
SLOW/FAST pedal
OVERDRIVE knob
BALANCE knob
RISE TIME knob
MODE knob
FAST SPEED knob
SLOW SPEED knob
DIRECT LEVEL knob
EFFECT LEVEL knob
DRIVE TYPE switch
Indicators
POWER indicator (serves also as battery check indicator)
EFFECT ON/OFF indicator
SLOW/FAST indicator
Connectors
INPUT A (MONO) jack (1/4 inch phone type)
INPUT B jack (1/4 inch phone type)
SPEED (EXP PEDAL) jack (stereo 1/4 inch phone type)
PHONES jack (stereo 1/4 inch phone type)
OUTPUT A (MONO) jack (1/4 inch phone type)
OUTPUT B jack (1/4 inch phone type)
AC Adaptor jack
Power Supply
DC 9 V: Dry battery (R6/LR6 (AA) type) x 6, AC Adaptor
Current Draw
85 mA (9 V max.)
* Expected battery life under continuous use:
Carbon: 6 hours
Alkaline: 10 hours
These figures will vary depending on the actual conditions of use.
Dimensions
173 (W) x 158 (D) x 57 (H) mm
6-13/16 (W) x 6-1/4 (D) x 2-1/4 (H) inches
Weight
1.1 kg / 2 lbs 7 oz (including batteries)
Accessories
Owner’s Manual (#G6017153R0)
Leaflet (“USING THE UNIT SAFELY,” “IMPORTANT NOTES,” and
“Information”) (#G6017303)
Dry battery (R6 (AA) type) x 6
* We recommend that alkaline batteries be used when replacing the batteries.
Options
AC Adaptor (PSA-series)
Expression Pedal (Roland EV-5)
* 0 dBu = 0.775 Vrms
* In the interest of product improvement, the specifications and/or appearance of
this unit are subject to change without prior notice.

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Dec. 2005 RT-20
Location of Controls
fig.panel
1
2
4
3
7
11
65 b a4
8 9
10

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Dec. 2005 RT-20
Location of Controls Parts List
[PART]
[SCREW]
No. PART CODE PART NAME DESCRIPTION Q’TY
1 G2357116R0 PEDAL PLATE 62X53 2
2 G2217749R0 LED PANEL 1
3 G2217192R0 PANEL 1
4 75D522N0R0 MINIMUM VR KNOB 8
5 G2567163R0 LED COVER 1
6 G2147880R0 LED LENS 1
7 G2217191R0 REAR PANEL 1
8 F3449415 ADAPTOR JACK KM02009AB 1
9 F3159104 SWITCH SS037-P222BHH-PE9 1
10 13449150 6.5MM JACK HLJ0544-0100109 4
11 F3449707 PHONE JK (STREO) HTJ-064-12DS 2
No. PART CODE PART NAME DESCRIPTION Q’TY
a H5029855 SCREW M4X8 HEXAGON BUTTON HEAD NI 4
b H5029901R0 SCREW M3X10 HEXAGON SOCKET (FE/NI) 4

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Dec. 2005 RT-20
Exploded View (1)
fig.bunkai1
Exploded View (1) Parts List
[PART]
[SCREW]
1
2
5
3
i
4
g
hRIGHT SIDE
LEFT SIDE
9
6
7
8
No. PART CODE PART NAME DESCRIPTION Q’TY
1 75E202T000 CASE 1
2 G2357111R0 CUSHION R 2
3 H5029851 PEDAL SHAFT 2
4 22157702R0 PEDAL GUIDE BUSH 2
5 22177109R0 COIL SPRING 2
6 G2357116R0 PEDAL PLATE 62X53 2
7 G2357115 PEDAL FOOT M8 2
8 G2187529R0 PEDAL R 1
9 75E202T1R0 PEDAL L 1
No. PART CODE PART NAME DESCRIPTION Q’TY
g H5029852 SCREW 4M3 FEBZC HEXAGON SOCKET BU 2
h H5039413 NYLON WASHER M4.1X7.5X0.5 BLACK 2
l H5039414 NYLON WASHER M5.1X9.5X0.5 BLACK 2

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Dec. 2005 RT-20
Exploded View (2)
fig.bunkai2
Exploded View (2) Parts List
[PART]
[SCREW]
26
c
k
21
20
d
27
24
No. PART CODE PART NAME DESCRIPTION Q’TY
20 G2147880R0 LED LENS 1
21 75D522N0R0 MINIMUM VR KNOB 8
24 G2217192R0 PANEL 1
26 G2217749R0 LED PANEL 1
27 G2567163R0 LED COVER 1
No. PART CODE PART NAME DESCRIPTION Q’TY
c H5029855 SCREW M4X8 HEXAGON BUTTON HEAD NI 4
d H5029901R0 SCREW M3X10 HEXAGON SOCKET (FE/NI) 4
k H5039521R0 NUT M7 8

8
Dec. 2005 RT-20
Exploded View (3)
fig.bunkai3-e
Exploded View (3) Parts List
[PART]
[SCREW]
a
a
12
18
11
16
j
14
15
10
13
17
Refer to Exploded View (4).
Enlargement
Enlargement
No. PART CODE PART NAME DESCRIPTION Q’TY
10 75D422E000 BOTTOM COVER 1
11 G2357118 BOTTOM FOOT 2
12 G2017621R0 BATTERY COVER 1
13 G2017620 BATTERY CASE 1
14 G2177308 BATTERY TERMINAL (+) 1
15 G2177309 BATTERY TERMINAL (-) 1
16 G2177307 BATTERY TERMINAL (+-) 1
17 G2257130 BATTERY INSULATING SHEET 1
18 G2537007R0 BOTTOM COVER LABEL 1
No. PART CODE PART NAME DESCRIPTION Q’TY
a H5019115 SCREW M3X8 PAN TAPPING-2 FEBZC 7
j H5019430 SCREW M2.6X5 BINDING HEAD 2

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Dec. 2005 RT-20
Exploded View (4)
fig.bunkai4
Exploded View (4) Parts List
[PART]
[SCREW]
f
e
25
b
23
28
31
b
29
30
No. PART CODE PART NAME DESCRIPTION Q’TY
23 G225712901 INSULATING SHEET 1
25 G2217191R0 REAR PANEL 1
28 G2197127 JACK SPACER 1
29 75E203J0R0 JACK BOARD ASSY 1
30 75E203P0R0 PANEL BOAD ASSY 1
31 G2147807 JACK HOLDER 1
No. PART CODE PART NAME DESCRIPTION Q’TY
b H5019110 SCREW M3X6 PAN TAPTITE FEZC 13
e H5039158R0 WASHER M9X14X0.5T NI 6
f H5039510R0 NUT M9X12X2T NI 6

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Dec. 2005 RT-20
Parts List
fig.part1e
SAFETY PRECAUTIONS:
The parts marked have
safety-related characteristics. Use
only listed parts for replacement.
NOTE: The parts marked # are new. (initial parts)
Due to one or more of the following reasons,
parts with parts code ******** cannot be supplied as service parts.
• Part supplied only as a component in a complete assembly
• Copyright does not permit the part to be supplied
• Part is sold commercially
The description "Q'TY" means a necessary number of the parts per one product.
CASING
G2357115 PEDAL FOOT M8 2
G2357116R0 PEDAL PLATE 62X53 2
G2017620 BATTERY CASE 1
G2017621R0 BATTERY COVER 1
75D422E000 BOTTOM COVER 1
G2357118 BOTTOM FOOT 2
# 75E202T000 CASE 1
# G2217192R0 PANEL 1
# G2187529R0 PEDAL R 1
# 75E202T1R0 PEDAL L 1
# G2217191R0 REAR PANEL 1
KNOB, BUTTON
75D522N0R0 MINIMUM VR KNOB 8
SWITCH
13129778 TACT SWITCH SKQKAH SW2, SW3 2
JACK, EXT TERMINAL
F3159104 SWITCH SS037-P222BHH-PE9 SW1 1
F3449415 ADAPTOR JACK KM02009AB JK8 1
F3449707 PHONE JK (STREO) HTJ-064-12DS JK1, JK4 2
13449150 6.5MM JACK HLJ0544-0100109 JK2, JK3, JK5, JK6 4
PWB ASSY
# 75E203J0R0 JACK BOARD ASSY 1
# 75E203P0R0 PANEL BOAD ASSY 1
IC
# 04012978 IC (CPU) UPD780034AGK IC11 1
02565501 IC (DSP) TC220CCA0AF-B01 (MR3) IC10 1
F5179125 IC (DC-DC) S-8520E33MC-BJS-T2 IC12 1
F5209150 IC (RESET) S-80130ALMC-JAP-T2 IC16 1
F5289102 IC (OP.AMP) NJM2100M 8P SOP IC3 1
15189261 IC (BIPOLAR OP AMP) M5218AFP-600E IC1, IC2, IC5 3
15289109 IC (BIPOLAR OP AMP) M5216FP-600D IC4 1
F5279309 IC (LED DRIVER) BU2090F-E2 IC13, IC14, IC15 3
02451434 IC (AD/DA) AK4552VT IC6 1
# F5249136R0 IC (CMOS) 74HC4052PW (TSSOP16) IC9 1
TRANSISTOR
F5139608 POWER MOS FET IRF7606 Q14 1
15329103 FET 2SK880GR-TE85R Q1,Q4 2
F5329530 FET 2SK879Y Q2, Q3, Q5, Q7, Q15 5
15319107 TRANSISTOR 2SC4116-GR (TE85R) Q9, Q10, Q11, Q12, Q13 5
DIODE
F5339137 DIODE SS14 VF=0.45V D7, D6 2
F5029126 POWER LED L-113GDT LED1 1
15029281 LED (RED) GL-3PR8 LED34, LED35 2
15339120 DIODE 1SS302 DA1, DA2, DA3, DA4, DA5, DA6, DA7 7
15339119 DIODE 1SS-352 D1, D2, D3, D4, D9 5
# F5029163R0 CHIP LED 19-21UBC/C470/TR8
(CHIP_BLUE)
LED2, LED3, LED4, LED5, LED6, LED7,
LED8, LED9, LED1
16
# F5029162R0 CHIP LED 19-21SURC/S530-A2/TR8 LED18, LED19, LED20, LED21, LED22,
LED23, LED24, LE
16
F5019309 ZENNER DIODE 02DZ5.1-Y D8 1

11
Dec. 2005 RT-20
RESISTOR
# F5419771R0 RESISTOR ARRAY RTA03-4D(0603) 10R RA5, RA4 2
02124645 MTL.FILM RESISTOR RR0816R-473-D R42, R46 2
01905001 MTL.FILM RESISTOR RR0816P-103-D R9, R16, R24, R37, R60, R67 6
F5399950 CHIP RESISTOR(1/2W) R-33 1/2W R33, R57 2
F2569127 POLY SWITCH MINISMDC075 R90 1
F5419726 RESISTOR ARRAY CRN34473J RA1, RA2, RA3 3
F5399158 RESISTOR 47K J R1, R2, R7, R8, R12, R13, R17, R23, R25, R28,
R32, R35,
27
F5399106 MTL.FILM RESISTOR 47 J R89 1
F5399118 MTL.FILM RESISTOR 330 R44, R68, R97 3
F5399154 MTL.FILM RESISTOR 27K J R94 1
F5399190 MTL.FILM RESISTOR 220K J R79 1
F5399130 MTL.FILM RESISTOR 2.2K J R93 1
F5399130 MTL.FILM RESISTOR 2.2K J R98, R99, R101, R102, R104, R105, R107,
R108, R110, R
16
F5399200 MTL.FILM RESISTOR 1M J R6, R31, R76, R95 4
F5399128 MTL.FILM RESISTOR 1K J R4, R14, R20, R64, R70, R96, R136, R137,
R138, R139, R
16
F5399128 MTL.FILM RESISTOR 1K J R100, R103, R106, R109, R111, R112, R114,
R115, R117
16
F5399150 RESISTOR 18K J R15, R27, R55, R66 4
F5399140 MTL.FILM RESISTOR 10K J R3, R11, R22, R30, R49, R58, R84, R87, R92 9
F5399140 MTL.FILM RESISTOR 10K J R124, R127 2
F5399170 MTL.FILM RESISTOR 100K J R5, R10, R18, R19, R29, R38, R39, R51, R52,
R61, R69, R
18
F5399104 MTL.FILM RESISTOR 10 J R47 1
F5399129 MTL.FILM RESISTOR 1.5K J R85 1
F5399101 MTL.FILM RESISTOR 0 J L1, L2, L4 3
POTENTIOMETER
# F3219119R0 POTENTIOMETER RD901F-40-125F-B50K-04D VR1 1
F3279819 ROTARY POT. W/CENTER
CLICK
RD901-40-125F-B54-0CD 50KB VR2, VR5, VR7, VR8 4
F3279802 POTENTIOMETER NO CLICK
50KB
RD901-40-125F-B54-00D VR3, VR4, VR6 3
CAPACITOR
F5359704 CHIP CAPACITOR (1608 TYPE) GRM39CH220J50PT C103, C104, C111, C112 4
F5359803 CHIP CAPACITOR (1608 TYPE) GRM39CH151J50PT C30, C48 2
F5359817 CERAMIC CAPACITOR GRM39B683K50PT 0.068 K C98 1
F5359812 CHIP CAPACITOR (1608 TYPE) GRM39B473K25PT C60, C61, C62, C63 4
F5359740 CHIP CAPACITOR (1608 TYPE) GRM39B222K50PT C9, C14, C35, C43 4
F5359780 CHIP CAPACITOR (1608 TYPE) GRM39B103K50PT C64, C66, C69, C77, C78, C79, C89, C90, C91,
C92, C93
11
F5359387 CERAMIC CAPACITOR GRM39B102K50PT 0.001 K C106 1
# F5359814R0 CHIP CAPACITOR 47P(0603SIZE) C1, C22, C24, C41 4
F3629703 CAPACITOR 47/16 C87,C107,C109 3
F3629703 CAPACITOR 47/16 C123, C121 2
# F3629695R0 CHEMICAL CAPACITOR 1U/50V C56 1
F3629700R0 CHEMICAL CAPACITOR 10U/16V (H=7MM) C4, C7, C8, C10, C11, C20, C21, C26, C28,
C32, C34, C46
17
F3629700R0 CHEMICAL CAPACITOR 10U/16V (H=7MM) C118, C119, C120, C141, C142, C143, C144 7
F5359318 CHIP CAPACITOR 10P C17, C54, C57, C141 4
# 13629550R0 CHEMICAL CAPACITOR 100U/16V C18, C27, C36, C40, C42, C53, C65, C100,
C113, C117, C
11
F5359311 CHIP CAPACITOR 100P C3, C6, C13, C15, C25, C44 6
# F5359828R0 CHIP CAPACITOR 0.47U (0603SIZE) C49, C31 2
# 13549329R0 CHEMICAL CAPACITOR 0.1U/50V C2, C23 2
F5359313 CHIP CAPACITOR 0.1 C122, C124, C125, C126, C127 5
F5359313 CHIP CAPACITOR 0.1 C19, C33, C37, C39, C55, C67, C68, C70, C71,
C72, C75
37
INDUCTOR, COIL, FILTER
F2449210 SMD COIL SLF7032T-4R7M1R7-2(4.7UH) L5 1
F2449209 COIL SLF7032T-151MR29-2(150UH) L6 1
F5409117 EMI FILTER NFM4516P13C204F C105 1
CRYSTAL, RESONATOR
F5299114 CRYSTAL HC-49SM 5MHZ X1 1
02673278 CRYSTAL CX-49G 11.2896MHZ X2 1
CONNECTOR
F3439183 CONNECTOR A2001WV2-13P P=2MM CN1, CN8 2
F3439160 CONNECTOR 53015-0210 2P P=2MM CN2 1
WIRING, CABLE
G3467250 WIRING 13P L=40MM P=2MM CN10, CN9 2
G3477165 FLAT CABLE 3P-70X6X6 P=2.0 CN7, CN6 1

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Dec. 2005 RT-20
SCREWS
H5019110 SCREW M3X6 PAN TAPTITE FEZC 13
H5019115 SCREW M3X8 PAN TAPPING-2 FEBZC 7
H5029852 SCREW 4M3 FEBZC HEXAGON SOCKET BUTTON
HEAD
2
# H5029901R0 SCREW M3X10 HEXAGON SOCKET (FE/NI) 4
H5029855 SCREW M4X8 HEXAGON BUTTON HEAD NI 4
H5039413 NYLON WASHER
M4.1X7.5X0.5
BLACK 2
H5039414 NYLON WASHER
M5.1X9.5X0.5
BLACK 2
H5019430 SCREW M2.6X5 BINDING HEAD TAPTITE P
FEZC
2
G2197127 JACK SPACER 1
H5039521R0 NUT M7 8
H5039510R0 NUT M9X12X2T NI 6
H5029851 PEDAL SHAFT 2
H5039158R0 WASHER M9X14X0.5T NI 6
PACKING
# G2357111R0 CUSHION R 2
G2607212 PACKING CASE LOWER 1
# G2627755R0 PACKING CASE UPPER 1
G2237613 REAR PAD 1
G2237614 SIDE PAD 1
MISCELLANEOUS
G3487163 WIRING BATTERY L=80MM 2P 1
G2257130 BATTERY INSULATING
SHEET
1
G2177308 BATTERY TERMINAL(+) 1
G2177307 BATTERY TERMINAL(+-) 1
G2177309 BATTERY TERMINAL(-) 1
# G2537007R0 BOTTOM COVER LABEL 1
22177109R0 COIL SPRING 2
G225712901 INSULATING SHEET 1
G2147807 JACK HOLDER 1
# G2567163R0 LED COVER 1
# G2217749R0 LED PANEL 1
# G2147880R0 LED SPACER 1
22157702R0 PEDAL GUIDE BUSH 2
ACCESSORIES (Standard)
G6017303 IMPORTANT NOTES JAPANESE/ENGLISH 1
# G6017152R0 OWNER’S MANUAL JAPANESE 1
# G6017153R0 OWNER’S MANUAL ENGLISH 1

13
Dec. 2005 RT-20
Checking the Version
Number
Enter Test Mode and execute “1. CPU, DSP Check” and “2. Version Check”
in this order.
About Updating
Exchange the circuit board for updating of system program. Follow the service
information when it’s needed.
Test Mode
Test Items
1. CPU, DSP Check
2. Version Check
3. Knobs Check
4. DRIVE TYPE Switch Check
5. Expression Pedal Check
6. Analog Bypass Waveform Check
7. Analog Bypass Route FET Switch Check
8. D/A Output Waveform Check
9. DSP Through (Output) Waveform Check
10. DSP Through (PHONES) Waveform Check
11. DSP Route FET Switch Working Check
12. Bypass Route Residual Noise Check
13. DSP Through Route Residual Noise Check
14. Battery Working Check
Items Required
• Monitor Speaker
• Expression Pedal (EV-5)
• Noise Meter
• AC Adaptor (PSA series)
• 47-kΩShort Plug x 2
• Oscilloscope
• Oscillator
Entering Test Mode
1. Rotate all of the eight knobs on the top panel counterclockwise fully.
2. While holding down the left and right pedals, connect the AC adaptor.
3. When the POWER LED lights, release the both pedals.
4. Press the left pedal within 2.5 seconds, then press the right pedal.
When the blue LEDs light, you will enter the Test Mode, and 1. CPU, DSP
Check is executed automatically.
Exiting Test Mode
Turn off the power.
Skipping
If you set the MODE knob previously as follows before entering the Test Mode,
you can specify the start point of the Test Mode.
MODE knob I: from 1. CPU, DSP Check (normal Test Mode)
MODE knob II: from 6. Analog Bypass Waveform Check
MODE knob III: from 8. D/A Output Waveform Check
MODE knob VI: from 12. Bypass Route Residual Noise Check
1. CPU, DSP Check will be always executed irrespective of the MODE knob’s
setting first. And next, when the right pedal is pressed, you will enter the test
item corresponding to the MODE knob’s setting. You can confirm which test
item you entered by checking the Virtual Rotor Display. (Refer to the
explanation of each test item.)
Any test item can be skipped by pressing the right pedal (SLOW/FAST pedal).
However, the test item 3, 4, and 5can be skipped.
Details for Tests
1. CPU, DSP Check
After entering the Test Mode, first, CPU and DSP will be tested. If they are
normal, two blue LEDs in the Virtual Rotor Display will light as the following
picture.
fig.01-cpudsp
If there are any problems, you cannot advance to the next test item. Then turn
off the power to finish the Test Mode.
2. Version Check
1. Press the right pedal to start the Version Check.
Version is shown in the Virtual Rotor Display as the following picture.
fig.02-cpuver
Ver. 1.00 Ver. 1.01
Ver. 1.02 Ver. 1.03

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Dec. 2005 RT-20
3. Knobs Check
1. Press the right pedal to start the Knobs Check.
fig.03-VR-panel
MODE knob
2. Rotate the MODE knob in the order of I, II, III, IV, III, II and I, and then
confirm the lighting position of LED in the Virtual Rotor Display moves
as the following picture.
fig.03-VR-mode
RISE TIME knob
3. When adjusting the RISE TIME knob to MAX, confirm the display of the
Virtual Rotor Display changes.
4. Confirm there is a feel of clicking at the center position.
Other knobs
5. When rotating the [EFFECT] knob clockwise fully from the MIN position,
confirm the display of the Virtual Rotor Display changes. And when
rotating it fully to the MAX position, confirm the display of the Virtual
Rotor Display changes again.
fig.03-VR-etc
6. In the same way, check [DIRECT], [BALANCE], [OVERDRIVE], [SLOW]
and [FAST] in this order.
7. Confirm there are feels of clicking at the center positions of the
[BALANCE], [SLOW] and [FAST] knobs.
4. DRIVE TYPE Switch Check
1. Press the right pedal to start the DRIVE TYPE Switch Check.
fig.04-DTYP-panel
2. Switch the DRIVE TYPE switch on the rear panel to GUITAR, and check
the SLOW/FAST LED lights.
3. Switch it to KEYBOARD in the same way, and check the EFFECT ON/
OFF LED lights.
4. Switch it back to GUITAR again, and check the SLOW/FAST LED lights.
I
II
III
VI
MIN MAX

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Dec. 2005 RT-20
5. Expression Pedal Check
1. Press the right pedal to start the Expression Pedal Check.
fig.05-EXP-panel
2. Connect an EV-5 to the SPEED (EXP PEDAL) jack.
3. Set the MIN knob of the EV-5 to 0.
4. Press down the pedal of the EV-5 to the heel side.
5. Confirm the red LED at the position of 12 o’clock in the Virtual Rotor
Display lights.
fig.05-EXP-1
6. Press down the pedal of the EV-5 to the toe side slowly.
7. Confirm the lighting position of the red LED in the Virtual Rotor Display
moves to 12, 3, 6 and 9 o’clock.
8. Press down the pedal of the EV-5 to the heel side slowly.
9. Confirm the lighting position of the red LED in the Virtual Rotor Display
moves to 9, 6, 3 and 12 o’clock.
fig.05-EXP-2
10. Remove the EV-5 from the SPEED (EXP PEDAL) jack.
11. Confirm the red LED in the Virtual Rotor Display turns off.
6. Analog Bypass Waveform Check
1. Press the right pedal to start the Analog Bypass Waveform Check.
fig.06-ANABYP-panel
2. Connect an oscilloscope to OUTPUT A (MONO) and OUTPUT B.
3. Connect an oscillator to INPUT A (MONO), and input a rectangular wave
of 200 Hz/500 mV p-p.
4. Confirm the output waveform will be like the following picture.
fig.06-ANABYP-1_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
5. Hold the signal to INPUT A (MONO), and insert a 47-kΩshort plug to
INPUT B.
6. Confirm the output waveform will be like the following picture.
fig.06-ANABYP-2_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
7. Remove plugs of INPUT A (MONO) and INPUT B, and then input a
rectangular wave of 200 Hz/500 mV p-p to INPUT B only.
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV

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Dec. 2005 RT-20
8. Confirm the output waveform will be like the following picture.
fig.06-ANABYP-3_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
9. Input the 200 Hz/500 mV p-p rectangular wave to both INPUT A
(MONO) and INPUT B.
10. Confirm the output waveform will be like the following picture.
fig.06-ANABYP-1_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
7. Analog Bypass Route FET Switch
Check
1. Press the right pedal to start the Analog Bypass Route FET Switch
Check.
fig.07-ANASW-panel
2. Confirm the output wave disappears and the following picture appears.
fig.07-ANASW-1_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
8. D/A Output Waveform Check
1. Press the right pedal to start the D/A Output Waveform Check.
fig.08-DA-panel
2. Connect an oscilloscope to OUTPUT A (MONO) and OUTPUT B.
(Or confirm they have been connected.)
3. Confirm the output waveform will be like the following picture.
fig.08-DA-1_70(200 mV/DIV, 1 ms/DIV)
<< 400Hz, 500 mV p-p +/-40 mV p-p >>
4. Remove the connection of OUTPUT B.
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV

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Dec. 2005 RT-20
5. Confirm the output waveform will be like the following picture.
fig.08-DA-2_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
6. And after removing the connection of OUTPUT A (MONO), connect an
oscilloscope to OUTPUT B.
7. Confirm the output waveform will be like the following picture.
fig.08-DA-3_70(200 mV/DIV, 1 ms/DIV)
<< 400Hz, 500 mV p-p +/-40 mV p-p >>
9. DSP Through (Output) Waveform
Check
1. Press the right pedal to start the DSP Though (Output) Waveform
Check.
fig.09-DSPTHOUT-panel
2. Connect an oscilloscope to OUTPUT A (MONO).
3. Connect an oscillator to INPUT A (MONO) and INPUT B, and input
rectangular waves of 200 Hz/500 mV p-p. (Or, confirm they have been
inputted.
4. Confirm the output waveform will be like the following picture.
fig.09-DSPTHOUT-1_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
10. DSP Through (PHONES) Waveform
Check
1. Press the right pedal to start the DSP Though (PHONES) Waveform
Check.
fig.10-DSPTHPHO-panel
2. Connect an oscilloscope to PHONES (L, R).
3. Confirm the output waveform will be like the following picture.
fig.10-DSPTHPHO-1_70(200 mV/DIV, 1 ms/DIV)
<< 200Hz, 500 mV p-p +/-40 mV p-p >>
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV
200mV/DIV, 1ms/DIV

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Dec. 2005 RT-20
11. DSP Route FET Switch Working Check
1. Press the right pedal to start the DSP Route FET Switch Working
Check.
fig.11-DSPSW-panel
2. Confirm the output wave disappears and be like the following picture.
fig.11-DSPSW-1_70(200 mV/DIV, 1 ms/DIV)
12. Bypass Route Residual Noise Check
1. Press the right pedal to start the Bypass Route Residual Noise Check.
fig.12-BYPNOISE-panel
2. Connect the 47-kΩshort plugs to INPUT A (MONO) and INPUT B.
3. Connect the noise meter to OUTPUT A (MONO) and measure the
residual noise.
Passing Value: -91 dBu or less (JIS-A)
4. Connect the noise meter to OUTPUT B and measure the residual noise.
Passing Value: -91 dBu or less (JIS-A)
5. Connect the noise meter to PHONES (L, R) and measure the residual
noise.
Passing Value: -91 dBu or less (JIS-A)
6. Connect monitor speakers to OUTPUT A (MONO) and OUTPUT B.
7. Give a shock (hard vibration) to the RT-20’s body, and confirm any
abnormal noise are not generated from OUTPUT A (MONO), OUTPUT B
or PHONES (L, R).
13. DSP Through Route Residual Noise
Check
1. Press the right pedal to start the DSP Through Route Residual Noise
Check.
fig.13-DSPNOISE-panel
2. Connect the noise meter to OUTPUT A (MONO) and measure the
residual noise.
Passing Value: -84 dBu or less (JIS-A)
3. Connect the noise meter to OUTPUT B and measure the residual noise.
Passing Value: -84 dBu or less (JIS-A)
4. Connect the noise meter to PHONES (L, R) and measure the residual
noise.
Passing Value: -84 dBu or less (JIS-A)
5. Connect monitor speakers to OUTPUT A (MONO) and OUTPUT B.
6. Give a shock (hard vibration) to the RT-20’s body, and confirm any
abnormal noise are not generated from OUTPUT A (MONO), OUTPUT B
or PHONES (L, R).
14. Battery Working Check
1. Remove the AC adaptor to turn off the power.
2. Put batteries into the battery box and connect a plug to INPUT A
(MONO).
3. Check the POWER LED lights.
200mV/DIV, 1ms/DIV

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Dec. 2005 RT-20
Block Diagram
fig.block@L
2120