W3CQH wrote:
wrote in message
...
A helix wound antenna with a double winding? Really?
- 'Doc

Double winding - in which direction and spaced how far apart in each
direction?



This URL, of a patent of an antenna which is growing in commercial use,
describes just such a winding and how it is constructed for real world
use. I am almost positive this is the "double helix winding method"
which Art is making reference to:

http://www.patentstorm.us/patents/7187335/fulltext.html

In particular, this reference in the patent:

"It has been found that interlacing a false winding into a current
enhancing unit (such as the top unit winding shown in FIG. 6) or a
radiation resistance unit (such as a helix as shown in FIG. 7) enhances
the bandwidth of the top unit as well as improves the current profile
along the antenna. The interlaced false winding has little effect on the
resonant frequency of the antenna system."

Regards,
JS