The Biquad Yagi has turned out to be an excellent directional antenna. Performing much better than I first thought it would. I did change the measurements from the link here: http://homemakeant.blogspot.co.uk/2008/06/biquad-yagi-24ghz-antenna.html
Although this only has 6 elements, 4 parasitic, 1 driven and 1 reflector it out performs a 15 element Yagi from eBay.
Making this antenna is all about preparation, making the measuring blocks as shown in the video. The video is a little longer than normal but I have included every step needed to build the Biquad Yagi.
A big thanks to Preslav Enchev for sending me the link.
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