Deutsche Version: Messung horizontaler Abstrahldiagramme von steppIR Yagi Antennen

Horizontal radiation patterns of three element steppIR Yagi antennas at the stations of DJ3AA (fig.1) and DL9CI (fig.2) were measured at the recording site of DL3AO (fig.3). The distances between transmitter and receiver are 10.4 km, resp. 6.2 km. The terrain profiles are presented in figs. 4-5 . There are no larger diffraction points included in the paths and the terrain around the stations is free from hills causing possible diffusive side reflections.

The measurements were made on the bands from 14 MHz to 28 MHz with the steppIR antenna settings “normal mode”, “reverse mode” and “bidirectional mode”. The following report, however  confines to the measurements and interpretations  made on 18 MHz in the setting “normal mode”. The measured patterns are compared and discussed with computer models.

Radiation Patterns of Three Element SteppIR Antennas: Measurements and Computer Models