When the dipole element pairs are spaced at 90° to each other, an omni-directional or circular pattern results. When both sets of dipoles are in line (collinear - see the DB404L illustration in Figure 1), the antenna has a directional characteristic, giving an elliptical pattern as shown in Figure 2. Also, see Figure 3 for gain variation with frequency for DB404 and DB404L antennas. The change from one radiation pattern to the other is easily accomplished. The banding clamps that hold the dipole