Kosmic Super-Quad 4-Bay (9.75x9.5) with FLAT vs SWEPT Bowties and Single Angled Reflector analyzed using 4nec2 to find Optimum Forward Sweep.
Dimensions obtained from EscapeVelocity's original post: http://www.dtvusaforum.com/dtv-hdtv-reception-antenna-discussion/8629-kosmic-antennas-superquad-4-bay-bowtie.html
AWG9 BowLength = 9.75-in, Bowtie Spacing = 9.5-in, Tine Separation = 5.0-in. Simulated SOURCE wire. AWG9 Feedline Separation = 1.5-in, except 1.25 at Crossovers. Crossovers = 4.75-in from Outer Bowties. Angled Screen Reflector 34"H x 28"W, with outer 2-in bent forward and center is 4.75-in from Bowties (Grid = 1"H x 2"W).
Optimum Forward Sweep for Full UHF Band Gain is now about 3-in, whereas Optimum for New UHF Band is about 2-in...although differences are small.....
But best F/B and F/R Ratios are provided when BowSwp is minimized, so it's a counterproductive tradeoff of whether you want to squeeze out a few fractions of a dB in Gain whilst losing several dB in F/B & F/R Ratio.... So if F/B & F/R are important in a given location, use BowSwp=1.0-in.
Date(s): 18 Mar 2010. Album by holl_ands. 1 - 21 of 21 Total. 3674 Visits.
enlarge 146KB, 485x1024 1 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties 3D View - BowSwp = 3-in
enlarge 198KB, 1024x696 2 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties UHF Raw and Net Gain
enlarge 235KB, 1024x696 3 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties UHF F/R and F/B Ratios
enlarge 285KB, 856x1024 4 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties Front View - BowSwp = 3.0-in [1 small box = 0.5-in]
enlarge 100KB, 320x1024 5 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties Side View - BowSwp = 3.0-in [1 small box = 0.5-in]
enlarge 93KB, 404x1024 6 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties Top View - BowSwp = 3.0-in [1 small box = 0.5-in]
enlarge 121KB, 1024x648 7 Super-Quad 4-Bay (9.75x9.5) with SWEPT Bowties UHF Raw Gain, F_R and F_R Ratios: BowSwp=3.0-in
