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The Projects/Filters (Envelope)/Dr. Quack (EHX™ Doctor Q™)

Project · Filters (Envelope)

Dr. Quack (EHX™ Doctor Q™)

Dr. Quack is a improved design of the EH™ Doctor Q™ filter from the AMZ site. The Geofex site offers a layout for this great little effect circuit.

Project files

Everything you need to build it

PDF · 1 pagePDF file of the layoutfrom the GEOFEX site↓PDF · 2 pagesNurse Quacky PDF Project file↓

Dr Quack Bill of Materials text file

PDF file of the Ready-For-Transfer Printed Circuit Board Layout

Parts layout

Parts Layout / Wiring Diagram

PDF file of the layout
PDF file of the layoutOpen full sizeDownload PDF

More about this project

Notes, sounds and related links

Note that neither the schematic nor the layout lists the unit values of the capacitors. The capacitor values are in microfarads.


This project is another take on an improved Electro-Harmonix™ Dr. Q™ Filter from the home-wrecker.com site and the schematic is here. Thanks to Dean Hazelwanter for the PCB design.