Terry-
Some years ago, I built a 2el 15M Quad using a closet pole as the boom,
2 12"-15" squares of 1/2" plywood as spiders (used 8 u-bolts per spider
and angle brackets for mounting to the boom), and 3/4" dowels of the
appropriate length (as I recall,the dowels were about 3" short, so I
drilled the ends and inserted 3/8" dowels. I used magnet wire for the
elements, an SO-239 mounted on a scrap piece of plastic, and a 1/4 wave
length of 72 ohm coax for matching.
I also built a 10M version at the same time. These antennas cost about
$60. (I have forgotten if that was for one or both). The boom bracket
was a 12" x 12" piece of 1/2" plywood using 2 u-bolts for the boom and 2
u-bolts for the mast ( which was a piece of a broom handle).
These wood on these antennas were never painted, and both have been used
for 10-12 years without being broken or damaged in any way. The beauty
of them is that they are really light, and they just take about 15
minutes to put together at the Field Day site. Arm strong rotor was a
1/8" piece of line tied to one of the spiders. We mounted these
antennas at 32 ft using SS-20 top rail (fence material ... it's heavy
wall and quite sturdy).
I also built one for 17M, painted it with house paint, and it was up for
about 2 years before the plywood spiders started to delaminate ... I
suppose if I had used some sealer on the edges that could have been
avoided.
Hope this answers gives you food for thought.
73- Fred Roberts, W6TKV
Riverside, CA 92505
Terry Hines wrote:
> I want to build a 15 meter quad for field day use only. Therefore, it
> doesn't have to be built to withstand winters or high winds. The
> length
> of the spreaders is about 8 feet long. I looked at small PVC pipe in
> ten foot lengths but it too flexible. Any ideas on light weight
> non-conductive spreaders, readily available and inexpensive?
>
> v/r terry N4ZH
>
>
>
----------------------------------------------------------------------------
---------------------------------
>
> Terry Hines <thines@mitre.org>
>
> Terry Hines
>
> <thines@mitre.org>
> 1820 Dolley Madison Blvd. M/S W625 ;McLean;Virginia;22102;USA Fax:
> (703) 883-1370
> Work:
> (703) 883-6493
> Additional Information:
> Last Name Hines
> First Name Terry
> Version 2.1
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