Racks

• https://en.wikipedia.org/wiki/Rack_unit
• Schroff Design Guide

Modular

• https://en.wikipedia.org/wiki/CV/Gate

Eurorack

• Doepfer’s DIY page
• Eurorack format Mechanical details Doepfer A-100 Mechanical details
• Wikimodules (FR)
• Eurorack Rails DIY Guide
• Tiptop Audio Z-Rails
• Elby Designs – EuroSynth – FracRak Comparisons

1U Eurorack

• intellijel Mechanical Specifications
• Pulplogic 1U Tiles
• Elby Designs – 1U Utility Tiles

Cool Synths

• Music From Outer Space
• The ASM-1 homepage

General Electronic Topics

• http://www.resistorguide.com/

Electronic CAD

• KiCad – A Cross Platform and Open Source Electronics Design Automation Suite
• http://gerblook.org

Electronic Design Tools

• Okawa Electric Design – Engineering Design Utilities
• Electronic references @ “hyperphysics”

Mechanical CAD

• FreeCAD
• Kicad StepUp – a new approach to export kicad board and modules in STEP AP214
• SheetMetal – Simple sheet metal workbench for FreeCAD
• Fasteners – FreeCAD workbench to add/attach various fasteners to parts

Microcontroller

• Atmel AVR Fuse Calculator
• AVR Fuse Calculator

Service manuals and schematics

• ElektroTanya

Various topics

• http://earth.nullschool.net/
• Blitzortung.org – Live lightning maps