On 6/27/2018 5:29 AM, jimlux wrote:
The Spiderbeam/DK4SQ type 40 foot poles are pretty skinny at the top,
but you don't have to use all the sections.
The 40 ft Spiderbeam pole we bought broke at the base in wind estimated
by experienced observers at around 45 mph. NOT recommended. Photos and
other details here. Their website claimed that "a special reinforcing
winding technique - several layers of fiberglass are wound in
alternating direction (criss/cross winding) - provides greatly increased
lateral and linear strength." W6GJB examined it after it broke and found
that it did NOT have that construction.
http://k9yc.com/80M-FDVertical.pdf
W6GJB has built a horizontal 40M dipole from a pair of Jackite poles,
which he says are better built.
73, Jim K9YC
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