Iterations on Boom Separation
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Why? To find out how whether changes in feed-boom spacing can be used to to adjust Z_in, and thence, SWR.

• Antenna: Log-Periodic Sawtooth Array
• Frequencies: Elements = 16.2-46 MHz; Range = 18-30 MHz; Analysis @ 24.89 MHz
• Impedance: near 300 Ohms
• Length: 16 m
• Elements: Count = 15; LHA = 10.344°; Diam = 1.628mm (14 AWG)
• Boom: Spacing = 50-275 mm, parallel; Diam = 2.588 mm (10 AWG)
• Segments: 120/Lambda
• Analysis: NEC2 via Nec2Go, version 2.1.24
• Quality: 0.93 ≤ AGT ≤ 1.02
• Download: ZIP Archive All models, three formats: NEC, ANT, and MAA.

SWR vs Boom Spacing @ 24.89&$160;MHz

Z_in between 200Ω & 300Ω, Gain dBi @ 24.89 MHz = 8.16 dBi

Z_in between 200Ω & 300Ω, Gain dBi @ 24.89 MHz = 8.34 dBi

Z_in between 200Ω & 300Ω, Gain @ 24.89 MHz = 8.46 dBi

Z_in between 200Ω & 300Ω, Gain @ 24.89 MHz = 8.54 dBi

Z_in between 200Ω & 300Ω, Gain @ 24.89 MHz = 8.61 dBi

Z_in near 300Ω, Gain @ 24.89 MHz = 8.52 dBi

Z_in near 300Ω, Gain @ 24.89 MHz = 8.58dBi

Z_in near 300Ω, Gain @ 24.89 MHz = 8.63 dBi

Z_in near 300Ω, Gain @ 24.89 MHz = 8.67 dBi

Z_in near 300Ω, Gain @ 24.89 MHz = 8.71 dBi

Observations: SWR almost unaffected even with very widely different boom-spacings (> 400%). Front/Back variations with fequency soften mildly between 50mm and 275mm.

I had intended to ask my cacluator for iterations only up to 250. Accidentally getting an extra, I included it anyway.

Boom Spacing vs Gain in Free Space