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holl_ands | Home > Bowties, Dipoles, Batwings & Rhombics > Browse:UHF Stick Dipole - No ReflectorUHF Bowties - NO ReflectorUHF Fractal Bowtie - No ReflectorUHF CM4248 Folded Dipole Bowtie (ONLY)91XG Dipole ONLY & Dipole+First DirectorUHF Batwing - No Refl & Screen Grid ReflUHF Small Rhombic StackUHF Double RhomboidVHF Stick Dipoles incl Horiz.Rabbit-EarsHi-VHF+UHF Stick Dipole - No ReflectorHi-VHF+UHF "VEE" Stick DipoleHi-VHF Bowties - No ReflectorLo+Hi-VHF 1-Bay Bowtie - No Reflector
UHF CM4248 Folded Dipole Bowtie (ONLY) UHF CM4248 Folded Dipole Bowtie (ONLY) analyzed using 4nec2. Dimensions from cm4248 4nec2 file posted by 300ohm, derived from Ken Nist's cm4248a.ez file. Also found in other Channel Master antennas. CM4248's Bowtie has two rearward facing stubs, the first results are for this "As-Built" configuration. Note that the stubs are effectively EXTENDING the overall length of the Bowtie Elements, resulting in a NARROWER Bowtie, which has LOWER Raw Gain than for a Bowtie without the stubs (see next analysis). Removing the stubs shifted the frequency of operation significantly upwards (see Wideband Charts at bottom), which was countered by Rescaling LARGER by the factor 1.38, as shown in the second set of results. This comparison emphasizes the importance of MODELING to determine results, rather than expecting Wideband Bowties to follow a 1/2-wavelength or full-wavelength or some other sort of commonly encountered "Design Rule". Date(s): 17 Jan 2012. Album by holl_ands. 1 - 29 of 29 Total. 13622 Visits.
enlarge 73KB, 1024x906 1 CM4248 Folded Dipole Bowtie, As-Built 3D View enlarge 132KB, 1152x450 2 CM4248 Folded Dipole Bowtie, As-Built Front View [1 big box = 1.25-inches] enlarge 217KB, 841x1024 3 CM4248 Folded Dipole Bowtie, As-Built Top View [1 big box = 1.25-inches] enlarge 140KB, 1024x686 4 CM4248 Folded Dipole Bowtie, As-Built UHF Raw Gain = 1.9 to 2.6 dBi enlarge 171KB, 1024x686 5 CM4248 Folded Dipole Bowtie, As-Built UHF SWR (300-ohms) Under 2.6 enlarge 148KB, 1024x686 6 CM4248 Folded Dipole Bowtie, As-Built UHF Impedance enlarge 324KB, 1024x1024 7 CM4248 Folded Dipole Bowtie, As-Built Azimuthal Pattern at 470 MHz enlarge 321KB, 1024x1024 8 CM4248 Folded Dipole Bowtie, As-Built Azimuthal Pattern at 590 MHz enlarge 326KB, 1024x1024 9 CM4248 Folded Dipole Bowtie, As-Built Azimuthal Pattern at 698 MHz enlarge 330KB, 1024x1024 10 CM4248 Folded Dipole Bowtie, As-Built Azimuthal Pattern at 758 MHz enlarge 331KB, 1024x1024 11 CM4248 Folded Dipole Bowtie, As-Built Azimuthal Pattern at 806 MHz enlarge 153KB, 1152x448 12 CM4248 Folded Dipole Bowtie, As-Built Side View [1 big box = 0.5-inches] enlarge 55KB, 1024x763 13 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled 3D View enlarge 129KB, 1152x433 14 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled Front View [1 big box = 1.25-inches] enlarge 204KB, 820x1024 15 CM4248 Folded Dipole Bowtie - No Stubs, Rescaled Top View [1 big box = 1.25-inches] enlarge 152KB, 1024x686 16 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled UHF Raw Gain = 2.1 to 3.9 dBi enlarge 171KB, 1024x686 17 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled UHF SWR (300-ohms) Under 1.5 enlarge 148KB, 1024x686 18 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled UHF Impedance enlarge 338KB, 1024x1024 19 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled Azimuthal Pattern at 470 MHz enlarge 324KB, 1024x1024 20 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled Azimuthal Pattern at 590 MHz enlarge 327KB, 1024x1024 21 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled Azimuthal Pattern at 698 MHz enlarge 331KB, 1024x1024 22 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled Azimuthal Pattern at 758 MHz enlarge 339KB, 1024x1024 23 CM4248 Folded Dipole Bowtie - No Stubs Azimuthal Pattern at 806 MHz enlarge 157KB, 1152x463 24 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled Side View [1 big box = 0.5-inches] enlarge 30KB, 791x1024 25 CM4248 Folded Dipole Bowtie, As-Built 4nec2 File enlarge 30KB, 791x1024 26 CM4248 Folded Dipole Bowtie, No Stubs, Rescaled 4nec2 File enlarge 30KB, 791x1024 27 CM4248 Folded Dipole Bowtie, No Stubs 4nec2 File - Prior to Rescale enlarge 156KB, 1024x686 28 CM4248 Folded Dipole Bowtie, No Stubs 4nec2 File - Prior to Rescale Wideband Raw Gain shifts UPWARD in Frequency OK Above 650 MHz enlarge 184KB, 1024x686 29 CM4248 Folded Dipole Bowtie, No Stubs 4nec2 File - Prior to Rescale Wideband SWR (300-ohms) also shifts UPWARD OK Above 650 MHz
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