>
> Would such a volume really & truly shed any new light upon Amateur radio
> application(s) of antenna phasing, or would the smart money be better off
> being saved, & consequently diverted toward the purchase of future editions
> of ON4UN's book...?
I'm going to read "Amateur radio application(s) of antenna phasing" as "Low
band application(s) of antenna phasing" given the context.
I pulled down some R.J. Mailloux articles from the IEEE and although I can't
look inside the book, I suspect it is going to be very microwave/radar
heavy, with lots of solutions on how to shift phase in waveguides, printed
circuits, that sort of thing that would be pretty useless for direct
application to low band arrays.
We have a different set of design criteria from radar and microwave
engineers. Typically, the developers of radar systems have a wide range of
fancy test equipment, software, and professional help at their beck and call
so they can do simulation and experiment and build prototypes of things and
do a lot of difficult testing on the prototypes. But once it works, it
works, and you can probably very rapidly build a bunch using standard
manufacturing techniques. The antennas are shining their beams into "free
space" ... I'm sure local variation causes the occasional weird problem
that ends up being written up as an editorial in an engineering publication
as a career lesson learned, but it's not the primary focus of array
engineering.
In contrast, that is almost certainly the PRIMARY thing that hams need to
tackle in building phased arrays: what can they build on *their* land with
*their* resources using some found/cheap/surplus components and simple
inexpensive test equipment and straightforward relatively low-math design
procedures.
It's a vastly different design problem.
In the end the basic array is the same. You have some desired currents in
some elements spaced in some pattern over some area.
But how a ham can reliably get there on 1.8MHz with limited test gear is
very much different than how professionals might get there at 5GHz, and my
guess is that when the book gets specific about particular designs, it's
going to be more about active beamforming on the microwaves than it is about
doing anything on HF. I'm sure there's a lot of general background material
in there, but I bet it's heavily mathematical in a way that might not be so
useful to a lot of people.
If I get a chance I will go check it out of the U of MD library and flip
through..
But you might just want to look at the policies of nearby universities with
technical libraries. There are likely a lot of technical books available
to a lot of people that are available this way.
If you feel like taking a trip into the city, it appears that the University
of Toronto Engineering and Computer Science library is open to the public
and has this book in their stacks:
http://discover.library.utoronto.ca/general-information/libraries/ENGI_CSCI
*http://tinyurl.com/mm54v9*
You probably can't check stuff out as a member of the general public but you
can go sit at a desk and read until you've decided on whether or not it
would be useful to you.
73
Dan
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