In radiophysics, the Luxemburg–Gorky effect (named after Radio Luxemburg and the city of Gorky (Nizhny Novgorod))[1] is a phenomenon of cross modulation between two radio waves, one of which is strong, passing through the same part of a medium, especially a conductive region of atmosphere or a plasma.
[2] Current theory seems to be that the conductivity of the ionosphere is affected by the presence of strong radio waves.
The strength of a radio wave returning from the ionosphere to a distant point is dependent on this conductivity level.
In other words, the ionosphere passes the station "B" signal with a strength that varies in step with the modulation (voice, etc.)
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