EURO UHF 15-Element FLAT LPDA (Log Periodic Dipole Array) analyzed using 4nec2 after Optimization using nikiml's Python Scripts. For 470-862 MHz EURO UHF Band.
In an LPDA, the Rear Element Length is about a half-wavelenght long at the lowest Frequency (e.g. 470 MHz). Separation between the REAR Element and the NEXT FORWARD is determined by SIGMA = Dij/2*Lj, which (with TAU) directly determines the overall LPDA Length. "Best" SIGMA is searched for using nikiml's Optimizer.
In the (Classic LPDA) Analysis below, Each subsequent Element Length is shorter than the preceding by the factor TAU and each subsequent Element Spacing is shorter than the preceding, also by the factor TAU = Li/Li+1 = Dij/Djk. Flat Boom Width = Element Width is determined using nikiml's Optimizer.
UHF Raw Gain = 9.9 to 10.6 dBi, F/B & F/R Ratio Min. = 25.7 dB and SWR (75-ohms) Under 1.5.
Date(s): 15Feb2019. Album by holl_ands. 1 - 24 of 24 Total. 1309 Visits.
enlarge 93KB, 1024x773 1 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in 3D View
enlarge 110KB, 1152x352 2 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Front View [1 large square = 1.25 inches]
enlarge 132KB, 1152x381 3 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Top View [1 large square = 5 inches]
enlarge 62KB, 1152x205 4 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Side View [1 large square = 5 inches]
enlarge 169KB, 1152x561 5 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in JUST Top Element [1 large square = 5 inches]
enlarge 169KB, 1152x556 6 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in JUST Bottom Element [1 large square = 5 inches]
enlarge 203KB, 1152x664 7 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in UHF Raw Gain =10.2 to 9.9 to 10.4 to 10.6 dBi UHF F/B & F/R Ratio Minimum = 24.9 dB [EVAL Total Gain includes AGT Corr on ALL Freqs]
enlarge 212KB, 1152x664 8 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in UHF SWR (75-ohms) Under 1.5
enlarge 241KB, 1152x664 9 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in UHF Impedance
enlarge 297KB, 1024x1024 10 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Azimuthal Pattern at 470 MHz
enlarge 296KB, 1024x1024 11 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Azimuthal Pattern at 550 MHz
enlarge 298KB, 1024x1024 12 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Azimuthal Pattern at 630 MHz
enlarge 298KB, 1024x1024 13 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Azimuthal Pattern at 710 MHz
enlarge 299KB, 1024x1024 14 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Azimuthal Pattern at 790 MHz
enlarge 299KB, 1024x1024 15 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Azimuthal Pattern at 870 MHz
enlarge 298KB, 1024x1024 16 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Elevation Pattern at 470 MHz
enlarge 297KB, 1024x1024 17 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Elevation Pattern at 550 MHz
enlarge 298KB, 1024x1024 18 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Elevation Pattern at 630 MHz
enlarge 299KB, 1024x1024 19 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Elevation Pattern at 710 MHz
enlarge 299KB, 1024x1024 20 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Elevation Pattern at 790 MHz
enlarge 299KB, 1024x1024 21 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in Elevation Pattern at 870 MHz
enlarge 71KB, 791x1024 22 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in 4nec2 File Includes Summary of Dimensions
enlarge 25KB, 791x1024 23 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in EVAL Summary of Performance
enlarge 54KB, 791x1024 24 EU 15-El FLAT LPDA - OPT Element Width = Boom Width = 0.75 in EVAL *.html Performance Summary File