This supplement is for a continuation of the Cornell radar observations at the Arecibo Observatory, including completion of work on the Radar Signal Comparator, which has suffered a number of unforseen delays. This device is an important aide to improvement of the quality of data obtainable with the radar, and will be used on their current research and by many other Arecibo users. The Cornell group sustains one of the leading research efforts in radar studies of the ionosphere. Their studies of large scale plasma motions, plasma turbulence and plasma instabilities has implications ranging from radio communications to fusion reactor technology.
