What is a Cobweb Antenna?

Cobweb Antenna is a small, light weight, multiband antenna, typically covering five ham radio bands from 14 MHz to 28 MHz. Cobweb antenna requires only one support and gives performance like a full size dipole on the five bands 20, 17, 15, 12 and 10m. Moreover, it can be fed by a single 50 Ohms coaxial cable. It has a horizontally polarized radiation pattern. There are five folded dipoles which are fed by a common balun. As it is an omnidirectional antenna, an antenna rotator is not needed. Size of 5 band version will be only 2.8 x 2.8 m, which makes it quite popular. Seven band version including 40m and 6m are also there.

Cobweb antenna gives a reasonable performance at even 10 feet height, though 20 feet height is desirable. Another advantage mentioned is that as it has the appearance of a washing line, acceptance by the ham’s family is good! As the dipoles get folded into square shape, impedance is around 12.5 Ohms and needs a 1:4 current balun in the terminal box. When a current balun is used, no additional choking on the coax is needed.