Patent covers claims to invention and trade of the inventor's product
- which in this case would be that antenna.

Right. And, the invention claimed must be novel (new), useful, and
non-obvious to a skilled practitioner of the art. In theory, it has
to actually work (otherwise it isn't "useful") but in most cases the
Patent Office seems to have stopped requiring any sort of actual
evidence on this point.

Antenna designs which were originally published decades ago (and that
seems to be most of them) cannot now be patented. Neither, in
principle, can slight or trivial or obvious variations on older
antennas.

In either case, the law provides the author or inventor a means to
pursue his loss of profit if these works are duplicated without
license or permission. With few exceptions, Common Law would suggest
that the practice of duplication by an individual for their own use
(and not to produce for sale or distribution) is allowed.

My understanding is that this is true to some extent for copyright
(the "fair use" principle). I've been told that it is _not_ true for
patented inventions. You're allowed to re-create the patented
invention yourself in order to study it, or to figure out a different
way of achieving the same goal (that is, a similar device which
doesn't actually infringe on the patent). However, re-creating the
patented invention for actual personal use is not allowed.

In practice, of course, this usually goes undetected and nobody gives
a hoot. Some patentholders have a practice of offering anyone who
asks a license to manufacture one (or a few) of the devices, for their
own use, with no royalty fee... but patentholders are _not_ required
to do so, or to license the patent to anyone at all.

Some years ago, the Bose corporation earned itself some bad blood in
the audiophile community, by sending a stern letter to Speaker Builder
magazine stating that a homebrew speaker-building article published
therein used a design which Bose felt infringed on one of their
patents (a "birdhouse" multi-chamber resonator design, I believe).
They accused Speaker Builder of "contributory infringement" of the
patent (i.e. encouraging others to infringe). This action was viewed
by many of the magazine's readers as an example of a big, monied
corporation bullying individuals.

As far as legal advice goes, caveat reader. As I pointed out above,
the law provides a means, the courts, not a guarantee. Further, it
should come as no surprise that even lacking this, you can always be
taken to court - even if you don't get out of bed for fear of being
sued.

A very good point!

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
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