Electronics:
the bridge between mechanics and programming
Obviously, deep knowledge of electronics requires many years of study
and consumes the professional life of electrical engineers. However,
a working knowledge of electronics can be acquired by just about
anybody who is motivated. Although the never ending process of miniaturization
continues to make the workings of electronic components more abstract
(unlike seeing the glow of a working vacuum tube), the wide availability
of parts, low cost, and huge amount of "how-to" information
on the Net, more than make up for it.
So, where does one start? Although I avoid promotion of commercial
entities, in this case I make no apologies: Radio
Shack. Yes, there are cheaper sources, and certainly the selection
of parts is limited, but despite what I asume to be a highly unprofitable
portion of their business, you can walk into any of their stores on
a Sunday afternoon, in just about any town, and take your pick from
a wall of resistors, transistors, IC's, and more. Amazing. Plus, they
stock excellent beginner's books-- I especially recommend anything by
Forest M. Mims III. To build a working knowledge of electronics, you
will need a solid understanding of Ohm's Law (requires grade school
algebra). And that's about it.
Most of the practical electronics necessary to get information from
the PC to a machine boils down to choosing between "you got 5 volts"
or "you ain't got 5 volts." A crucial benefit here, is that
although you can readily fry parts by screwing up, you won't die from
electrocution when working with so small of a voltage. There are many
ways to learn basic digital electronics. A few of my favorites include:
Nuts and Volts magazine -- I
absolutely love this monthly rag. It is written for non-engineers, but
packs a tremendous wealth of practical know how between its covers.
Radio Shack's various experimenters packages and books.
If you're getting serious, and want deeper and a more authoritative
reference-- The Art of Electronics, by Horowitz and Hill, is
it.
From Bits, to Bytes,... to
Bots -- a course I have taught to kids as young as 12, serves as
an example of one strategy for doing elementary digital electronic experiments,
involving connection of a PC to the real world.