Popov demonstrated a coherer based receiver to the Russian Physical and Chemical Society on 7 May 1895 but did not patent it or publish it outside Russia in a form clearly available to Marconi at the time. Both men were building on the same coherer research already published by Oliver Lodge and others, so the resemblance between their early receivers does not by itself prove either man copied the other.
What would resolve this A primary correspondence, laboratory notebook or contemporary press account placing Marconi in direct contact with Popov's published results before Marconi's own 1896 patent filing; none has surfaced in the sources consulted for this entry.
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