designs. Some of these are just spam
traps, so make sure your popup filter
is working on your computer. Many
others are great sharing resources
with good information.
For example, David Cook’s
has several 555-based circuits
specifically designed for use as a robot
controller. While he shows some
circuits designed onto printed circuit
boards, most can be constructed on
solderless breadboards (and, in fact,
many of his examples do just this).
An added bonus is the electronics
theory and how-to describing the
operation of the circuit, rather than
just providing a bare schematic.
I provide several links to popular
circuit and schematic sites in the
Sources section here, but this is
something you’ll want to experiment
with yourself using search engines.
Next in line as an excellent
resource for yesterday’s electronics is
magazine back issues on CD-ROM or
DVD-ROM. Both SERVO Magazine and
its sister publication Nuts & Volts are
available on CD-ROM, going back to
2004 for both publications. Other
electronics magazines like Circuit
Cellar offer electronic back issues;
Circuit Cellar dates back to 1988.
Some of your other favs may be
available on CD-ROM or DVD-ROM, as
well. Be sure to check the publisher’s
website for details.
A distinct advantage of electronic
back issues is that they don’t take up
nearly as much space as the printed
edition, and most come with a search
feature for combing through the
articles and columns.
Finally, don’t forget your
neighborhood public library, where
you can find older electronics how-to
and construction books — the perfect
thing for the concept of going back to
basics. You don’t need the latest and
greatest on electronic microcontroller
design. One of the Forrest Mims
books dating back to the late 70s is
the perfect find. Electronics hasn’t
changed since then, and many of
Forrest’s designs for the 555 timer
chip, 741 op-amp, light sensitive
diode, and others have been used on
countless robots over the years.
Don’t forget you can find many
of these same circuits in reprint form
if you want your own permanent
copy. Go to the Nuts & Volts online
look under the Circuits category.
I’ve found that old back issues of
now-defunct electronics magazines a
rich source of ideas and education.
Many of the better public libraries
provide these back issues on
microfiche, microfilm, or CD-ROM.
Ask the reference librarian for a list of
publications provided in these formats.
For example, starting in the June
1980 issue, Radio-Electronics ran a
series of articles on the Unicorn-1:
an R2-D2-like robot said to cost
(at that time) only $400 to build.
The series discussed not only the
electronics of the robot, but the
mechanical construction as well, and
was very thorough.
There were similar one-off articles
and series on robot building before
and after, in Radio-Electronics, Popular
Electronics, and the descendent
magazines from these, such as
Electronics Now. Rummage through
the shelves at your library long
enough and you’ll dig up plenty of
treasures. If your library has really old
issues, you might find some tube-based robot designs dating back to
the late 40s and 50s. Proof that the
art and science of amateur robot
building has been around for a long,
You may also be able to find
some of these back issues online. For
instance, Scribd (
has reprinted the Unicorn-1 series, and
the reprint is fairly good quality. Many
— no, make that most — of the online
reprints of magazines are home scans
with quality so poor it’s often hard
to read the parts labels on the
schematics. They’ll do in a pinch, but
as these resources tend to come and
go (the scans are often not made with
permission of the current owner of
the magazine rights), I won’t list any
here. Pages may be in HTML form
where you can view them in your
browser, or compiled into a tidy PDF
document that can be opened with
Adobe Acrobat or Foxit.
Find a circuit for just about anything on the Discover Circuits site.
Pages link to other websites with diagrams, schematics, and how-to.
can be reached
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