[Elecraft] Attic Ant.-Closed Loop vs. Open Ends?

[Jeff]

David, G3UNA, wrote:
> ...My 'doublet' was nearly a loop, ie it followed
> the beams around the loft.  The ends were left open, about a foot apart...

I have some questions for the group.  How would one decide whether the ends
should be left open, versus connected together to make a loop?  (I never
could figure out how to model antennas using EZNEC.  It should be called
HARDNEC.)  Does it make a lot of difference?  Using a tuner near the
feedpoint, which way would give a better match on more bands (160-10m), open
or closed ends?  Which way would yield stronger signals in the most
directions?  Is it the case that, below a certain total wire length, the
ends should be left open, but above that length, they should be connected
together?  I guess the only way an indoor antenna of typical length would
match on 160m, even with a tuner, would be if the ends were connected
together and the whole thing was treated as a very bent end-fed wire working
against ground and a counterpoise.

Thanks & 73,
Jeff, WB5GWB
Long Island, NY
K2 #821