Most of my hobby projects involve electronics. Over the years I've built and rebuilt countless things, starting with simple mods to toys to the computer and emulation stuff here, once I get an idea in my head it isn't long before the soldering iron is out.
I started playing with electronics when I was 5 or 6, pulling battery powered toys apart. A little later, my dad gave me a stack of old circuit boards and a soldering iron. After a while, I'd gathered a pretty good collection of parts and would spend afternoons trying them out in various configurations. My mum bought me one of those 30-in-one electronics project kits, which helped me to learn how to read schematics and understand the various component's properties and how they interact.
Over the years, this understanding has gradually built on itself through research and experimentation. I wouldn't go so far to say I have anything like a complete understanding of electronics theory, but I do have a good working knowledge of the subject. Enough to allow me to assemble my own circuits, repair things and work out how to get a solution to a problem using electronics.
Knowing this stuff has helped me in many of the projects I've worked on. A lot of product designers just do aesthetics and leave "how it works" to the engineers, I have enough understanding to blur the line (a little), between designer and engineer.
Electronics is a huge and rewarding subject. An electronic gadget is more than the sum of it's parts; components are like the individual notes in a piece of music. With electronics you can make music and a lot more. If you want a device to provide a sophisticated level of interaction, almost without exception electronics is the key.
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