Data obtained in radiowave propagation experiments on the path Kirunai Stockholm

In order to study different ionospheric conditions, signals received from a pulsed transmitter over a 19 year period were recorded continuously on film with a time resolution of a few minutes, and with a resolution in the time of arrival of simultaneous pulses of about 100 micron s. The density of the echoes provides a rough indication of the signal amplitude. An example of the records and the evaluated parameters is given and the measuring system is described.