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A 15el 28 Ohm 144MHz Optimised Wideband Low impedance (OWL) Yagi

Revised  February 2010

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 here

Visit HERE to learn how to make the OWL Match/Balun

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!

 

PLEASE NOTE:

 

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