A 4 element LFA Yagi for 24MHz with a 5.25mtr boom
Premium commercial versions of this antenna at Innovantennas
This is a high-gain, wideband LFA (Loop Fed Array) Yagi which covers 24.890 - 24.980MHz with an SWR of less than1.1:1. 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
8.99dBi @ 24.930MHz
25.53dB @ 24.930MHz
SWR: Below 1.1:1 from 24.89MHz to 24.980MHz
Stacking:
Distance: 6m
Gain: 11.29dBi (16.73dBi at 20m above real ground)
F/B: 29.27dB
Construction details:
Refer to the above drawings
Antenna Dimensions for UK/USA and European sized tubing
Taper: Inner Section, 5/8 inch or 16mm tube (total length 1.0m). Outer section 1/2 inch or 13mm tube (3.048m, 1.524m each side). End sections as per below schedule and in 3/8 inch or 10mm.
Spacing End Section Length (All below sizes in Metres)
Reflector 0 1.608
DE1 .365 1.054 - FEEDPOINT
DE2 1.546 1.054
D1 2.512 1.358
D2 5.250 1.144
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 4el at 20m above ground
2 x 4el LFA, 6m spacing between, bottom antenna 20m up
SWR Plot
Any questions, please ask!
Justin G0KSC