G0KSC SC0609L 9el 50Mhz Yagi Antenna with a 12.2 Metre Length Boom
This antenna has been redesigned and represents what i believe to the the 'ideal boom length' for an OWA direct feed 50Ohm Yagi. This can be seen in the model in the super flat SWR, the high levels of F/B ratio along with the excellent gain and pattern.
The model below is designed with 12.7mm / 1/2 inch elements and also a 12mm version below . If you require a version of this antenna with another diameter wire, Email me and I will remodel. It is NOT POSSIBLE to simply resize the elements when using a VERY different diameter wire and get the best performance possible. Element positions also need to change for the ideal antenna to be achieved again. Please read all the way down this page, there are other versions of this antenna using tapered elements too. As I have more requests, I will remodel in other element diameters and tapers and publish those too.
Enjoy the antenna and if you build, Please Send me photos!
K7JA upgrades his 7el G0KSC OWA to a 9el G0KSC OWA (Centre of the cluster)
Dimensions in Metres with 1/2 inch elements
Element spacing:
- Ref = 0
- Driven = .838
- D1 = 1.012
- D2 = 1.946
- D3 = 3.588
- D4 = 5.562
- D5 = 7.750
- D6 = 10.154
- D7 = 12.234
Element sizes per element half:
- Ref = 1.477
- Driven = 1.461
- D1 = 1.3915
- D2 = 1.379
- D3 = 1.346
- D4 = 1.322
- D5 = 1.302
- D6 = 1.278
- D7 = 1.272
Performance figures @ 50.150Mhz:
- Froward Gain: 13.93dBi free space
- Front to Back: 28.12dB
Dimensions in Metres with 12mm elements
Element spacing:
- Ref = 0
- Driven = .838
- D1 = 1.012
- D2 = 1.946
- D3 = 3.588
- D4 = 5.562
- D5 = 7.750
- D6 = 10.154
- D7 = 12.234
Element sizes per element half:
- Ref = 1.4775
- Driven = 1.4615
- D1 = 1.392
- D2 = 1.3795
- D3 = 1.3465
- D4 = 1.3225
- D5 = 1.3025
- D6 = 1.2785
- D7 = 1.2725
Performance figures @ 50.150Mhz:
- Froward Gain: 13.91dBi free space
- Front to Back: 29.39dB
Azimuth Plot
Elevation Plot
This fantastic antenna at 20m up
An Excellent SWR to go with the fantastic pattern!
