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Keywords from Image Description:
SpreadFNPS. Ray diagram of Spread event The uneven distribution of free electrons in the layer causes HF to spread out or have other unusual propagation characteristics Strahlendiagramm eines SpreadFEreignisses Die ungleichmige Verteilung freier Elektronen in der FSchicht lt Kurzwellen sich aufspreizen oder andere ungewhnliche Ausbreitungseigenschaften