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a71br
12-17-2008, 03:58 AM
The "Spiderbeam" is a light weight beam which is ideally suited for portable operations. Due to the construction with light glass fibre tubes and special antenna wire the antenna can be packed down to a transport length of only 120cm. With only 9kg weight is is well suited for dx-peditions.
Improved version 2: The new version is even easier to assemble, many details have been improved. The glassfibre tubes are no longer telescopic but tubular, so they cannot slide down unwanted. No more tie wraps, no more sticky tape, the wire elements keep a constant distance. The wire insulators are now ready to use, no more epoxy glue required here. The wire elements are fastened to the tubes with re-useable Velcro(r), no more tie wraps required. Also electrically the antenna has been improved. The new Spiderbeam is less susceptible to changes in environment, bandwidth on 10m has been improved, a future extension to 12/17m has become possible.

The spiderbeam consists of three yagis on one boom. 3 elements for 20m, 3 elements for 15m and 4 element on 10m. This results in a gain of up to 9dBD over real ground. Due to the light construction a small aluminum telescopic mast is suffcient.

The Spiderbeam is a kit, it has to be assembled before first use. At first the wire elements with the guy lines have to assembled. Even if the assembly has become much easier you should do this at home and not in the DX spot... The setup itself takes about 45 minutes. Due to the use of special antenna wire and high quality Kevlar guy lines a high stability and reproduceability is achieved. The feed is done with one common balun, only one feed line required.

http://home.datacomm.ch/hb9abx/spider1.jpg ==http://www.wimo.com/bilder/spiderbeam_klein.jpg

n9jr
12-18-2008, 12:53 AM
I have long been interested in portable antennas, and have often found them to be lacking when put to the test in the field. My worst experience was with the SuperAntenna MP-1. Not a fun experience.

You mentioned 9dbd - which I expect would be the gain on 10m, what do they publish for gain on 20m? And F/B data as well?

But if that is you parked along the road with a tribander and a radio it sure looks cool!

Joe N9JR

a71br
12-18-2008, 05:02 AM
If you need more detail see this link http://www.spiderbeam.com/pdf_files/spider_specification_english.pdf

and this http://www.spiderbeam.com/documents/index.php?coID=36

i wish i can do it we don't have Bamboo here.

http://www.dxqsl.net/attachment.php?attachmentid=139&stc=1&d=1229580685

1. Basic Antenna Principle
The basic antenna principle is quite simple. No magic involved.
Start with a normal 3 element yagi and bend the director and reflector in a V-Shape:


http://www.spiderbeam.com/img/pages/3ele_to_spider.jpg

2. Developing the spider beam
The spider beam is a multiband design. Three monoband "bow-and-arrow yagis" are interlaced on the same supporting cross:

http://www.spiderbeam.com/img/pages/skizze_spiderbeam_englisch.jpg