Space physics, Experiments, Inverse problems - Daily Reports (seiðr). Writings about various topics in plasma physics, radio science, space physics, rockets, radars, aurora, remote sensing, geophysics, radio astronomy, inverse problems, outdoors activities, electronics, and software defined radio. The web page of the radio science group at University of Tromsø.
Once of the things found in the storage area behind the Arecibo Observatory is the ionosonde antenna. It's not there for storage, but located there, presumably so that it is further away from radio astronomy instrumentation, causing less interference. This is a dual polarized log-periodic HF antenna. I don't know which company designed and made this, but it is a beautiful antenna indeed. I happened to be there at the right moment, when there was a circular halo right above the antenna.
The antenna sustained a bit of damage during the hurricane Maria, but I'm told that it will soon be operational again. I've got some ideas on using my spread spectrum ionosonde/HF radar concept there, so I hope the antenna is back up and running soon.