Canvey Island, Essex, England Justin@g0ksc.co.uk
Twin boom quad
144MHz LFA Yagis
144MHz LFA Yagis

Low Noise LFA Yagis designed by G0KSC free to build for personal use.

144MHz LFA Yagis
70cms LFA Yagis
70cms LFA Yagis
Twin-Boom G0KSC Quads
G0KSC Twin-Boom Quads
Twin-Boom G0KSC Quads
G0KSC Custom Dish feeds - Above installation @ HB9Q
Custom low-noise dish feeds
Custom low-noise dish feeds
G0KSC Custom Dish Feeds

Above installation @ HB9Q

G0KSC Custom Dish feeds - Above installation @ HB9Q
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Read Time: 2 - 4 minutes
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