A trap dipole can fit within that length if the ends (80 meter elements)
are folded, e.g.:

http://home.comcast.net/~jdegood/coaxtrap/

73, John NU3E

SMØIMJ wrote:
Hi all,
Anyone that have an idea about a wire antenna (folded dipole, trapped
something, etc.) that can be used on a limited space (e.g. on a smaller roof
11*6 meter)?
I mainly use verticals but need something for local (national) 80m QSOs.

cheers,
Hans / SMØIMJ