[TowerTalk] Fiberglass masts and AKI special

[Doug Turnbull]

Hi All,
Spiderbeam makes fiberglass mast sections designed for antenna supports.
They come in four or five foot lengths and telescope out 40 feet for one
model and 60 feet for the other.   They are like very heavy duty roach
poles.  I plan to use a good thirty plus feet extending from and clamped to
a three inch diameter stainless pipe which reduces to two inch diameter.
This pipe extends some seventeen feet outside the head unit of a seventy
foot crank up tilt over tower.   I envisage a total height which will vary
between ninety and one hundred ten feet.   The top section will bow outwards
and a wire will be run to the ground with a relatively short horizontal
section.   The top wire will be from the wireman a very light but strong
stranded steel copper coated wire supported by a two mm diameter Kevlar
rope.   The bottom ninety feet of so of this inverted L will be a heavier
copper wire.   Thus I hope to have a really high inverted L for the Stew
Perry and the CQWW 160M contests.   I will bring it down pretty quickly if
the wind picks up to a more sedate 80/90 feet.  Four raised radials will be
used with this antenna.  The antenna is a variation of the AKI Special
designed by JA5DQH  and illustrated on page 9-73 of Low Band DXing by ON4UN.
Mine will not have anything like the sharp bend that JA5DQH used and this
one will be higher with more of a vertical run.  There are no other antennas
on this tower.   

 

Anyone else try this one.

           73 Doug EI2CN