[TowerTalk] substandard aluminum

[Ward Silver]

> Telrex built antennas before the days of PCs. They did it the old 
> fashioned way. They built them to last!
> (snip)
> wa3gin

The old-fashioned way was to use rules of thumb and excessive safety margins 
because the mechanics of the material were not sufficiently well understood 
to support less rigid designs.  It's the same way with buildings - the 
modern core-and-curtain skyscraper only became possible because of advances 
in the understanding of materials and in improved modelling tools.  Before 
that, it was essentially brute force pillar-and-beam construction.

Certainly, many of the those older buildings are still with us and will be 
around for a long time. Nothing wrong with 'em.  However, if you want the 
improved efficiency of operation and materials and the advanced designs of 
modern buildings, then you will have to use the new techniques.

In the HF antenna world, ask yourself if it would be practical to build, 
say, a C31XL using the Telrex methods and materials? The Telrex monobanders 
are FB antennas, but how much would the new design weigh?  The sheer problem 
of supporting such a massive antenna would exacerbate failure modes related 
to loading on the boom, clamps, and mounting plates. How much would it cost 
to build, install, and support such an antenna if made survivable?  At some 
point, the older techniques fail to give practical solutions and new 
techniques are required.

73, Ward N0AX