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G0KSC SC0609L 9el OWA Yagi for 50Mhz

Written by G0KSC

G0KSC SC0609L 9el 50Mhz Yagi Antenna with a 12.2 Metre Length Boom

updated June 2010

Please read the whole page, there are several versions of this antenna listed.

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