"Steve" wrote in message
.. .
The only question I have now is probably a daft one but here goes.......
the
plans for this antenna specify that the reflector should be at position 0
on
the boom and D13 should be at 8300mm relative to the position of the
reflector.. Where would one drill the hole for the reflector ? i.e how far
in from the end of the tube, and how far past the hole for the last
director
would the boom actually end ?

There is a mechanical engineering standard on that. The issue came up re the
A310 design after the NY crash where the tail tore off . I believe the
standard is 2 hole diameters. I looked at my VHF beams, and they are about
25mm.

Tam/WB2TT