FM Double-Hoop plus Vertical Dipole Omni (IN CENTER OF HOOP) analyzed using 4nec2.
This antenna responds to both Horizontal and Vertical Polarization, although they are only have equal Raw Gain at about 97 MHz. Below 97 MHz, Vertical Gain is reduced by up to 9 dB and above 97 MHz Horizontal Gain is reduced by up to 5 dB. However, Total Gain (Vert. + Horiz.) remained between -1.2 and +2.3 dBi across all angles and frequencies. SWR (300-ohms) was under 6.2
Although Raw Gain varies quite a bit, the Omni-Directional azimuthal coverage remains very consistent across all angles. However, users may be unhappy with performance if a station is only transmitting one Polarity.
21 Dec 201115 items4425 visitsAlbum by holl_ands
enlarge 43KB, 662x1024 1 Double-Hoop + Vertical Dipole In Center 3D View
enlarge 112KB, 348x1024 2 Double-Hoop + Vertical Dipole In Center Front View [1 big box = 5-inches]
enlarge 269KB, 1024x990 3 Double-Hoop + Vertical Dipole In Center Top View [1 big box = 2.5-inches]
enlarge 163KB, 1152x584 4 Double-Hoop + Vertical Dipole In Center FM Total Raw Gain FORWARD
enlarge 147KB, 1152x584 5 Double-Hoop + Vertical Dipole In Center FM Total Raw Gain to SIDE (0-deg)
enlarge 171KB, 1152x584 6 Double-Hoop + Vertical Dipole In Center FM SWR (300-ohms) under 6.2
enlarge 168KB, 1152x584 7 Double-Hoop + Vertical Dipole In Center FM SWR (75-ohms) Excessive on Higher Freqs
enlarge 154KB, 1152x584 8 Double-Hoop + Vertical Dipole In Center FM SWR Impedance
enlarge 110KB, 354x1024 9 Double-Hoop + Vertical Dipole In Center Side View [1 big box = 5-inches]
enlarge 333KB, 1024x1024 10 Double-Hoop + Vertical Dipole In Center Azimuthal Pattern at 87 MHz
enlarge 321KB, 1024x1024 11 Double-Hoop + Vertical Dipole In Center Azimuthal Pattern at 91 MHz
enlarge 332KB, 1024x1024 12 Double-Hoop + Vertical Dipole In Center Azimuthal Pattern at 97 MHz
enlarge 335KB, 1024x1024 13 Double-Hoop + Vertical Dipole In Center Azimuthal Pattern at 103 MHz
enlarge 332KB, 1024x1024 14 Double-Hoop + Vertical Dipole In Center Azimuthal Pattern at 108 MHz
enlarge 49KB, 791x1024 15 Double-Hoop + Vertical Dipole In Center 4nec2 File
