A 3 element LFA Yagi for 28MHz with a 3.45mtr boom
Premium commercial versions of this antenna at Innovantennas
This is a high-gain, wideband LFA (Loop Fed Array) Yagi which covers 28 - 28.500MHz with an SWR of less than1.6:1. It has options with both UK/USA and European sized tube and has a 3 section taper.
This Antenna has been modelled using NEC4 and confirmed by FEKO. This is thousands of dollars of the very latest antenna design software available and the results are highly accurate. When loading into your software, you will see similar SWR but not the same. Please do not alter the model, build to these dimensions for the best results.
Contact me if you are unsure what correction (if any) you require for the element holders/stand-offs you will use or any other questions you may have or require different element diameter.
Antenna Layout and Construction:
Performance
8.51dBi @ 28.250MHz
19.83dB @ 28.250MHz
SWR: Below 1.6:1 from 28MHz to 28.500MHz
Construction details:
Refer to the above drawings
Antenna Dimensions for UK/USA and European sized tubing
Taper: Mid Section, 5/8 inch or 16mm tube (total length 1.829m). Outer section 1/2 inch or 13mm tube (3.047m). End sections as per below schedule and in 3/8 inch or 10mm.
Spacing End Section Length (All below sizes in Metres)
Reflector 0 1.216
DE1 .706 0.698 - FEEDPOINT
DE2 1.691 0.698
D1 3.450 0.924
Adjust loop width for best SWR upon completion. Fit antenna with a 1:1 balun
Polar Plots
Azimuth Plot of this super antenna
Elevation plot of this antenna
1 x 5el at 15m above ground
SWR Plot
Any questions, please ask!
Justin G0KSC