Electronics as science
Electronics is a science, and a very
accessible science at that. With other areas of scientific
study, expensive equipment is generally required to perform
any non-trivial experiments. Not so with electronics. Many
advanced concepts may be explored using parts and equipment
totaling under a few hundred US dollars. This is good,
because hands-on experimentation is vital to gaining
scientific knowledge about any subject.
When I starting writing Lessons In
Electric Circuits, my intent was to create a textbook
suitable for introductory college use. However, being mostly
self-taught in electronics myself, I knew the value of a
good textbook to hobbyists and experimenters not enrolled in
any formal electronics course. Many people selflessly
volunteered their time and expertise in helping me learn
electronics when I was younger, and my intent is to honor
their service and love by giving back to the world what they
gave to me.
In order for someone to teach themselves a
science such as electronics, they must engage in hands-on
experimentation. Knowledge gleaned from books alone has
limited use, especially in scientific endeavors. If my
contribution to society is to be complete, I must include a
guide to experimentation along with the text(s) on theory,
so that the individual learning on their own has a resource
to guide their experimental adventures.
A formal laboratory course for college
electronics study requires an enormous amount of work to
prepare, and usually must be based around specific parts and
equipment so that the experiments will be sufficient
detailed, with results sufficiently precise to allow for
rigorous comparison between experimental and theoretical
data. A process of assessment, articulated through a
qualified instructor, is also vital to guarantee that a
certain level of learning has taken place. Peer review
(comparison of experimental results with the work of others)
is another important component of college-level laboratory
study, and helps to improve the quality of learning. Since I
cannot meet these criteria through the medium of a book, it
is impractical for me to present a complete laboratory
course here. In the interest of keeping this experiment
guide reasonably low-cost for people to follow, and
practical for deployment over the internet, I am forced to
design the experiments at a lower level than what would be
expected for a college lab course.
The experiments in this volume begin at a
level appropriate for someone with no electronics knowledge,
and progress to higher levels. They stress qualitative
knowledge over quantitative knowledge, although they could
serve as templates for more rigorous coursework. If there is
any portion of Lessons In Electric Circuits that will
remain "incomplete," it is this one: I fully intend to
continue adding experiments ad infinitum so as to
provide the experimenter or hobbyist with a wealth of ideas
to explore the science of electronics. This volume of the
book series is also the easiest to contribute to, for those
who would like to help me in providing free information to
people learning electronics. It doesn't take a tremendous
effort to describe an experiment or two, and I will gladly
include it if you email it to me, giving you full credit for
the work. Refer to Appendix 2 for details on contributing to
this book.
When performing these experiments, feel free
to explore by trying different circuit construction and
measurement techniques. If something isn't working as the
text describes it should, don't give up! It's probably due
to a simple problem in construction (loose wire, wrong
component value) or test equipment setup. It can be
frustrating working through these problems on your own, but
the knowledge gained by "troubleshooting" a circuit yourself
is at least as important as the knowledge gained by a
properly functioning experiment. This is one of the most
important reasons why experimentation is so vital to your
scientific education: the real problems you will invariably
encounter in experimentation challenge you to develop
practical problem-solving skills.
In many of these experiments, I offer part
numbers for Radio Shack brand components. This is not an
endorsement of Radio Shack, but simply a convenient
reference to an electronic supply company well-known in
North America. Often times, components of better quality and
lower price may be obtained through mail-order companies and
other, lesser-known supply houses. I strongly recommend that
experimenters obtain some of the more expensive components
such as transformers (see the AC chapter) by salvaging them
from discarded electrical appliances, both for economic and
ecological reasons.
All experiments shown in this book are
designed with safety in mind. It is nearly impossible to
shock or otherwise hurt yourself by battery-powered
experiments or other circuits of low voltage. However,
hazards do exist building anything with your own two
hands. Where there is a greater-than-normal level of danger
in an experiment, I take efforts to direct the reader's
attention toward it. However, it is unfortunately necessary
in this litigious society to disclaim any and all liability
for the outcome of any experiment presented here. Neither
myself nor any contributors bear responsibility for injuries
resulting from the construction or use of any of these
projects, from the mis-handling of electricity by the
experimenter, or from any other unsafe practices leading to
injury. Perform these experiments at your own risk! |