Canvey Island, Essex, England
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: 4 - 8 minutes
A 15el 28 Ohm 144MHz Optimised Wideband Low impedance (OWL) Yagi

Premium commercial versions of this antenna at Innovantennas

The OWL by G0KSC provides the benefits of both OWA (Optimised wideband Array) 50 Ohm antennas with those of traditional low impedance antennas. More information on the OWL can be found in the CONSTRUCTION menus above.

Do not look at the gain figure of this antenna and compare with other 15 element 144MHz Yagis. Compare the gain, F/B and bandwidth together against other antennas of a similar boom length. With 17.04dBi and a boom less than 9.8M long, this antenna will be a winner for field days and the rural Ham radio operator. Class leading G/T figures too!


  • Visit 'Making the OWL Match' for more information on the recommended matching methods
  • Please add 2mm to each element to allow for insulator correction if using insulators similar to G0KSC. If through boom/insulator/element bolts are used, add 3mm
  • This antenna is a non critical design and therefore will take little fine tuning (if any)
  • This is antenna has a super wide and low SWR curve with one of the best patterns found on a low impedance antenna of this length

Performance UK/USA Version

Forward Gain:                           17.04dBi at 144.300MHz

Front to Back Ratio:                 25.58dBi at 144.300MHz

Peak Gain:                                 17.08dBi

Peak F/B:                                25.63dB

Bandwidth:                               2MHz below 1.1:1 (1.6MHz with EU sized tube) 

Build Dimensions for UK/USA/EU Version (dimensions and lengths are all the same)

Element  Spacing in metres Half element Length in metres   Element Notes

Reflector               0                                   .5155                  3/8 inch or 10mm tube

DE                       .210                               .5095                  1/2 inch or 12mm tube

D1                       .318                               .4845                  3/8 inch or 10mm tube

D2                       .726                               .4685                  3/8 inch or 10mm tube

D3                     1.335                               .4575                  3/8 inch or 10mm tube

D4                     2.054                               .4505                  3/8 inch or 10mm tube

D5                     2.855                               .444                    3/8 inch or 10mm tube

D6                     3.692                               .4385                  3/8 inch or 10mm tube

D7                     4.563                               .433                    3/8 inch or 10mm tube

D8                     5.459                               .430                    3/8 inch or 10mm tube

D9                     6.362                               .4255                  3/8 inch or 10mm tube

D10                   7.263                               .424                    3/8 inch or 10mm tube

D11                   8.170                               .4185                  3/8 inch or 10mm tube

D12                   9.101                               .418                    3/8 inch or 10mm tube

D13                   9.852                               .431                    3/8 inch or 10mm tube

Antenna Plots

Fantastic Azimuth plot of this 15el 144MHz OWL Yagi

The Elevation plot is really clean too. A quiet antenna compared with most!

Ever seen a 28 Ohm antenna like this one before? Watch how many now appear on the Internet but remember where you saw them first!

The G0KSC OWL element layout. Note the close spacing of the first 3 elements which give the OWL its extra gain and wide bandwidth.

As always, or if you have difficulty at all, please Email me!

Justin G0KSC