UHF 5-Element FLAT Yagi, Channel Master CM-4040, analyzed using 4nec2. I took all measurements directly from Antenna, which includes a built-in 1:1 Balun. Boom Length = 8.33-in [VERY Compact]
UHF Gain = 7.2 to 5.9 to 7.1 dBi, F/B & F/R Gain = 6.0 to 22.7 dB (POOR-FAIR-EXCL) and SWR (75-ohms) Under 3.1 (FAIR). Note WIDE BEAMWIDTH Azimuthal Antenna Pattern with 70-60 degree Beamwidth, deceasing with Frequency.
Bi-Directional Hi-VHF Gain = 2.3 to 1.8 dBi FORWARD and 2.5 to 2.2 dBi to REAR is slightly HIGHER. But Hi-VHF SWR (75-ohms) is Very EXCESSIVE.
============================================================= Compare to OPTIMIZED UHF 5-El Folded Dipole Yagi, which provides 2-3+ dB higher UHF Gain and much better F/B & F/R Ratios on lower Channels with OPTIMIZED Boom Length = 22-in: UHF Raw Gain = 7.3 to 9.4 to 8.9 dBi, F/B & F/R Ratio Min. = 13.4 dB (GOOD) and SWR under 3.1 (GOOD).
Nearly Omni-Directional Hi-VHF Gain = -0.5 to 0.4 dBi FORWARD and -0.4 to 0.6 dBi to REAR is slightly HIGHER. But Hi-VHF SWR (300-ohms) is Very EXCESSIVE.
PS: Jointly Optimizing UHF and Hi-VHF should improve Hi-VHF performance, perhaps at expense of UHF.
Date(s): 17 Jan 2017. Album by holl_ands. 1 - 28 of 28 Total. 2353 Visits.
enlarge 246KB, 723x1024 1 UHF 5-El FLAT Yagi - CM-4040 Top View [1 large square = 1.25 inches]
enlarge 338KB, 1024x959 26 UHF 5-El FLAT Yagi - CM-4040 Top View - Assembled Held together by two screws on Dipole Elements and Slip-On Rear Plastic Piece
enlarge 296KB, 1024x840 27 UHF 5-El FLAT Yagi - CM-4040 Bottom View - Dis-Assembled All Plastic except for Aluminum Elements and press-fit Copper to Al. Dipole connections
