> > 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.
Other than a Force 12 80/40 antenna that is in close
competition, my telrex 40 meter yagi is the worse large
antenna I ever owned.
The balun was absolute junk. It had an unbelievable amount
of unbalance on the balanced terminals, and a considerable
amount of shunt inductive reactance. The thin elements would
break every time we had winds over 60 MPH, even after I
strutted them.
The element tuning was nowhere near optimum.
I rebuilt it with 6061T6 and now it rebounds from ice even
when the tips hang vertical. Winds don't phase it at all.
73 Tom
_______________________________________________
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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