Not Enough Spots Thanks to the current low sun spot cycle, the 40 meter band arguably provides the best HF radio propagation. The problem with this band, is that a half wave dipole wire antenna is 20 meters long. If you string that from a mast or a tree, you may need 30 to 40 meters of space for the wire and ropes. Most modern backyards are not that large. One solution is to upgrade to a Country Manor House, but for most radio amateurs, that would be too much lawn to mow. On the other hand, fitting a 40 meter band dipole into the attic of a regular sized home or cottage, certainly seems impossible, but it is actually quite easy: Curl the dipole up into a helix! Clue Up On Helices The following NEC card stack defines a dipole made from two helices, wound around a 5 meter length of "Two by Four" lumber, for a 75% overall size reduction, which should fit into the attic of most homes. "Two by Four" lumber is actually 1.5 by 3.5 inches, or 38 by 89 mm in s
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