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!
- 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
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!