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holl_ands | Home > Multi-Bay Bowtie Antennas > UHF 4-Bay Bowties with Reflector > Browse:Ch22 FF4 4-Bay Bowtie + DARNEW UHF Free-Form 4-Bay + FlatScreenReflUHF Free-Form 4-Bay + DblAnglReflUHF FF4 SingleAngleRefl - DeepSidelobesUHF M4 (10x9.5) Super-4-Bay+DARUHF M4 (9.5x9.0)+DAR Flat vs Swept BowsM4 (9.5x9.0)+DAR Flat v Swept BowsM4 (9.5x9) + Various FLAT Refl. WidthsM4 (9.5x9.0) + 40x34 FLAT Refl at 5-inUHF M4 (9.5x9.0) 4-Bay+FLAT Grid at 5.5"UHF M4 (9.5x9.0) 4-Bay+FLAT Grid at 16"M4 (9.5x9) + Various Number of RRs - OPTUHF KosmicSuperQuad+DAR FlatvsSwept BowsUHF Actual CM4221 Flat Bows & ReflectorUHF CM4221a.ez.nec Flat Bows & ReflectorUHF CM4221HD (Hacked) - 16 ReflRodsUHF CM-4221HD - 10-in WhiskersUHF CM4221HD (Hacked) + Director RodsCM4221HD (Hacked) + Stub FilterAntennacraft U-4000 - 9 Reflector RodsA-D Old DB-4 4-Bay Bowtie with Reflector
UHF CM4221a.ez.nec Flat Bows & Reflector Channel Master CM4221 4-Bay (7.8x8.0) Bowtie (Ken Nist's cm4221a.ez file) with Screen Reflector analyzed using 4nec2. It appears that Ken Nist simply took HALF of the CM4228a.ez file, as evidenced by the off-set axis. BowLength = 7.8-in, Bowtie Spacing = 8-in, Tine Separation = 5.5-in. Feedline Separation = 1.25-in, with 0.8-in at Crossover. Center of Crossovers 4.0-in from Center of Outer Bowties. Screen Reflector (36"H x 20"W).  Separation from Bowties = 4.5-in. FWIW: Measurements on an ACTUAL CM4221 antenna were somewhat different. Date(s): 17 Aug2009. Album by holl_ands. 1 - 11 of 11 Total. 6121 Visits.
enlarge 0KB, 618x1024 1 cm4221.a.ez.nec 4-Bay Bowtie - 3D View enlarge 0KB, 763x1024 2 cm4221.a.ez.nec 4-Bay Bowtie - Front View [One small box = 0.5 inch] enlarge 79KB, 791x1024 3 cm4221.a.ez.nec 4-Bay Bowtie - 4nec2 File Some revisions were needed to Ken Nist's file: http://www.hdtvprimer.com/SIMS/ enlarge 0KB, 1024x819 4 cm4221.a.ez.nec 4-Bay Bowtie - UHF Raw Gain enlarge 0KB, 1024x819 5 cm4221.a.ez.nec 4-Bay Bowtie - UHF SWR (300-ohm) OPTIMUM MATCH....such as it is for Low Freqs enlarge 0KB, 1024x819 6 cm4221.a.ez.nec 4-Bay Bowtie - UHF Impedance Note Excessive Reactance at Low Freqs enlarge 0KB, 1024x819 7 cm4221.a.ez.nec 4-Bay Bowtie - UHF SWR (150-ohm) SWR (150-ohm) is worse overall then with 300-ohm. enlarge 0KB, 1024x819 8 cm4221.a.ez.nec 4-Bay Bowtie - UHF SWR (600-ohm) SWR (600-ohm) degrades Low Freq SWR even more than 300-ohm. enlarge 0KB, 273x1024 9 cm4221.a.ez.nec 4-Bay Bowtie - Side View [One small box = 0.5 inch] enlarge 0KB, 448x1024 10 cm4221.a.ez.nec 4-Bay Bowtie - Top View [One small box = 0.5 inch] enlarge 0KB, 768x1024 11 CM4221 Hung from the Rafters Note Reflector Screen flare is to the Rear for slightly wider Beamwidth.
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