UI design in the physical world

I am working on a new Arduino project related to amateur radio. It is a variation of a SO2R switch box.

Normally I would play with a CAD program or Visio to work through various design ideas. Today I decided to go old school and pull out a pencil and a notepad.

It is interesting working on user interface ideas for things that are based in physical world that you will touch with your fingers. Button styles, spacing, and feedback back are all considerations.  --I am still pondering my options as I have not found what I am looking for yet.

 

73 de NG0R