There is lot of designs in the net, but this one is interesting because it is designed to be simple and easy to reproduce or mass produce /as You can see from the pictures/.
This 5ghz feeder is coming from Greece. http://www.5ghz.gr
Here dome pictures :
Design and blueprints π
End product : tubes and feeding and connectors.
This looks like experimental builds :
Interesting is simple materials – copper tube and sheet, and connectors. Everything is soldered – no weak points in this design.