Ihad also started a small ship-to-shore electronics ervice business along with the above. With this array of devices waiting for repair, I was literally drooling over high quality test equipment to make my job easier, but school tuition pretty much kept my back to the wall financially. So, I
had to do with what I had, or design and make up
barebones test gear on my own. Bottom line is that I
never lost my love or desire for quality test equipment.
The other reason was that in designing my own
equipment or eventually buying commercial equipment, I
was blown away by the quality of workmanship and
cleverness of design. As far as I was concerned, quality
test gear design and construction was the yard stick by
which all other circuits were measured.
As time passed, my interest increased further in this
area, mainly due to the design challenges it presented and
the rewards of completion. A couple of years later and as
luck would have it, I was hired by an R&D company that
specialized in test equipment design and prototyping. As
the old saying goes, “ I never had to work another day in
my life.”
Now, I am not trying to say that test equipment
should be the ultimate goal in your electronics interest.
However, once the initial architecture is laid out for any
design, test equipment will be required for both the
starting point and ending point for those projects. It all
comes down to standards and a point of reference (try
building a house without the use of a tape measure or
level).
Since I have written many articles on test equipment
construction, I thought I would back-track this time and
look at this from a different perspective: Why do we need
TE (Test Equipment)? What variety of TE do we require?
What is the best progression of adding TE? And, last but
not least, what are the economics of arriving to a fully
equipped test bench?
I will address all these issues as sanely as possible
based on my 40 years of building, acquiring, and using TE.
This article will be mainly pointed towards analog
electronics, but much of this spills over to digital use as
well. Even with digital design and when all the “number
crunching” is completed, it still comes down to analog
electronics. This is especially true with ever-increasing
speeds now employed — not to mention I/O ports to the
real world such as sensors, etc. In reality, there is only one
wave shape in the physics of electronics: the pure sine
wave — which is analog!
All other wave shapes are an algebraic addition of
many sines waves added together versus time. For
example, a perfect digital square wave is really derived
from a fundamental sine wave and all its odd harmonics
(hundreds to thousands) that have decreasing amplitude
with each increasing order of harmonic content — again,
analog! (Be sure to check out Richard Agard’s article on
harmonics in this issue.)
All in all, I can hardly imagine an electronics
enthusiast without some sort of test bench. This can be as
simple as a folding table and a couple of hand tools, along
with a cheap DMM (Digital MultiMeter). Or, it can be as
elaborate as a spare room just loaded with TE and a full
complement of tools and accessories to go with it. This
wide span of facilities depends on which direction(s) your
hobby takes you, how deeply you get into it, and the years
of involvement.
Interestingly, a lot of top rated engineers in the past all
had very elaborate setups right in their own home. Most
of them agreed that some of their best ideas originated
there due to a quieter and more relaxing atmosphere than
the typical workplace. So, location in your own home is
something to keep in mind.
So, why do we need test equipment in the first place?
Well, for a multitude of reasons, such as initial design and
prototyping of the circuits we build; final adjustment and
Any of you that have followed my N&V articles over the past 10
years certainly know by now that I am a test equipment freak. This
stemmed from a couple of reasons. Early on in getting my start in
electronics and while still in the process of getting my education, I
did what many other students were doing at that time — dabbling
in radio and TV repair. This not only produced a small income to
help with tuition fees, but also gave us invaluable hands-on insight
to the actual working conditions of various circuits.
Setting Up a Test Bench
22 October 2015