What might the results look like?

On eclipse day, the main source of HF radio absorption will diminish. However the HF radio reflecting ionospheric layers above will remain as they were for much longer.  What we expect to happen is the  strengths of radio signals between  crossing the region of the shadow will increase for the duration of the eclipse. By recording the changes in the strength of the signals during the eclipse, compared to a control day, then one is effectively measuring the amount of absorption normally present.   The plot below shows the type of data we hope to collect. (click on image to enlarge)  With the data from lots of radio amateurs covering many different paths, we hope to produce a 2-D map of the changes in ionospheric absorption across Europe (something like the illustration below). This has never been attempted before on this scale. (click on image to enlarge) With this kind of information we hope to improve our understanding of the  upper atmosphere  where the radio waves are reflected and ultimately aid global commuications.