Solar Eclipse 2017 recordings of medium-wave AM broadcast band from near Upsala, MN, U.S.A.

In the AM broadcast band (535-1705kHz), there are roughly two modes of broadcast station signal coverage, one of which occurs in the daytime, and the other at night. During the day time, signals are propagated by ground wave and and not usually heard well beyond 150km from the transmitter. However, at night, an absorptive region in the ionosphere, the D-layer, disappears, allowing signals to refract off higher regions of the ionosphere, and to be heard hundreds and even thousands, of kilometers away from the transmitter. During the solar eclipse of 21 August 2017, signals were observed changing from daytime to nighttime mode and then back again as the moon's shadow moved across the continental USA. The radio stations in this band use amplitude modulation, which requires a strong stable carrier wave, well suited for observing changes in signal strength over a time period. The solar eclipse time period coincided with a group of thunderstorms near this location, so the files are heavily corrupted with a large amount of static crashes, interfering with weaker signals. Included in these files is one provided by Microtelecom ("perseusv5demo.exe") for playback of the .wav files, plus a help file, "PerseusV5QuickTuningGuide.pdf". As well, there is a reference file to assist in identifying signals ("canusa-Jan2019.pdf"). Finally, there is set of instructions for using the software, along with instructions for using "Perseusv5demo.exe" to extract a time series of signal power for an individual radio station's signal ("Using Perseusv5demo to create signal strength time series-MD.pdf"). Finally, referencing the article archived at http://hamsci.org/sites/default/files/publications/2019_am-eclipse2017_hall-patch.pdf , will give the user of these files an idea of how radio reception datasets from different locations can be used to compare the effects that the solar eclipse had on radio propagation.