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The Projects/Boosters & Volume/MXR™ MicroAmp™

Project · Boosters & Volume

MXR™ MicroAmp™

This booster has been popular since inception, over 30 years ago and for good reason.  It's also a nice simple little booster to build.

Schematic

Schematic

MicroAmp Schematic
MicroAmp™ SchematicOpen full sizeDownload PDF

Parts layout

Parts Layout / Wiring Diagram

MicroAmp Parts Layout and Wiring Diagram
MicroAmp™ Parts Layout and Wiring DiagramOpen full sizeDownload PDF

What you will need

Bill of Materials

Version 2009December10 · Copyright 2009 JD Sleep · Permission refused for posting/serving this file from any site other than www.generalguitargadgets.com · Trademarks are property of their owners

Resistors

Resistor IDValue3-band Marking4-band Marking
R122Mred-red-blue
R210Mbrown-black-blue
R31kbrown-black-redbrown-black-black-brown
R456kgreen-blue-orangegreen-blue-black-red
R5 (Volume Control)500k Reverse Log
R62k7 (2.7k)red-violet-redred-violet-black-brown
R7100kbrown-black-yellowbrown-black-black-orange
R8100kbrown-black-yellowbrown-black-black-orange
R9470 ohmyellow-violet-brownyellow-violet-black-black
R1010kbrown-black-orangebrown-black-black-red
R111kbrown-black-redbrown-black-black-brown

Capacitors

Capacitor IDValueTypePossible Marking
C10.1µFFilm104
C247pFCeramic or Film47pF
C34.7µFTantalum or Aluminum Electrolytic4.7µF
C41µFTantalum or Aluminum Electrolytic1µF
C515µFTantalum or Aluminum Electrolytic15µF

Potentiometers

Part IDValueType
R5 - Volume Control500kReverse Log Taper

Other

Part IDPart Name
IC1TL061 or other single opamp
D11N4001 or 1N914 Diode (Small Blue diode in the Kits)
D2LED
J1Stereo quarter-inch jack
J2Mono quarter-inch jack
J3DC Jack
B19 volt battery (Not Included in the Kit)
Sw1Heavy Duty 3PDT foot switch 9v battery snap, 24 gauge stranded hookup wire, Enclosure, Knobs, Solder

More about this project

Notes, sounds and related links

Ready to build? We have the kit.

Buy a MicroAmp™ Complete Kit. Includes all the parts and materials you need to build one, all for about the price you would pay for a PCB and parts.

Would you like a Ready to Solder Circuit Board for this project?  Note: If you buy the kit, the Ready-to-Solder Printed Circuit Board (RTS PCB) is included in the kit.  You do not need to purchase this Ready to Solder Circuit Printed Board if you buy the kit.