Rob Frohne, Ph.D., P.E.
E.F. Cross School of Engineering
Walla Walla College
If nobody creates new prototypes, then the state
of the art never advances. It all depends on what you enjoy and what
your goals are. Some hams like operating, some like experimenting.
He also observed that today materials ARE available at reasonable
prices, and that we DO have available microcontrollers.
He's RIGHT. He's also right that being able to write machine code
to control the antenna is an interesting exercise, and provides
Unspoken is the ability to design an antenna to work on 40 and 30
meters...using longer BeCu tape than the SteppIR can fit in its
molded motor housing.
Rob also observed that the price of parts from SteppIR was a bit higher
than he felt reasonable. Might be true, might be they don't want to
experimentation which would require support. (Customer service can be
an incredible consumer of resource.)
Which brings me back to The Experience Curve. The theory says you CAN
achieve lower costs, not that they automatically appear as you add
experience. It's also possible that they haven't reached the region where
they can start to squeeze out manufacturing efficiencies, or they haven't
As for my design sketches from 1979, Rob, I'm afraid they won't add much
value today. At the time, I was using an apple II-C and Visicalc to run
a $15M optical spectroscopy business. We were writing machine control code
in Forth on a pdp-11 for data acquisition, and discrete logic to
control detector systems. Available compute power to solve the yagi
or simply to use lookup tables for element lengths was prohibitively
As a result, no effort was made beyond concept sketches.
HOWEVER, as appealing as prototype development is, my assertion still
Prototypes always cost more than manufactured units, in one way or another.
Possibly because you're trying something new, and it takes time. Possibly
you have to providesupport yourself. Possibly because custom housings are
and the tooling isn't amortized over a production run.
OTOH, if you're having fun, it may not matter!
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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