[Tommy Gober] built this Yagi-Uda antenna that has some handy design features. The boom is a piece of conduit with holes drilled in the appropriate places. The elements are aluminum arrow shafts; a good choice because they’re straight, relatively inexpensive, and they have #8-32 screw threads in one end. He used some threaded rod to connect both sides of the reflector and director elements. The driven elements are mounted offset so that a different machine screw for each can be connected to the appropriate conductor of the coaxial cable. The standing wave ratio comes in right where it should meaning he’ll have no trouble picking up those passing satellites as well as the International Space Station.

We Make Money Not Art recently visited the LABoral Art and Industrial Creation Centre in Gijón, Spain. The installation that left the strongest impression on [Regine] was the WiFi sightseeing telescope built by Clara Boj and Diego Diaz. Spain is in a situation similar to the USA: A few years ago many municipal WiFi projects launched only to be squashed because of theoretical unfair competition with local utilities. Now commercial projects like WeFi, Whisher, and FON encourage people to “share” their WiFi. Observatorio (Observatory) is designed to provide insight into the current state of local WiFi. It uses a highly directional Yagi antenna to collect wireless access data from the local area. The antenna has a 30deg aperture which is matched to a camera with an identical field of view. The observer sees the camera’s viewpoint with the WiFi data overlaid showing where accesspoints are and whether the AP is open. WMMNA also recommends you check out the WiFi Camera which photographs electromagnetic space.