A very early radio map of the U.S. showing location of major radio stations operating in 1925. The country is divided by use of printed color into nine "Radio Districts" and four time zones. There is also a "Log By Wave Length" in which one can record the signal strength of stations received. Folded into yellow card board covers 23x9.5 with "Bankers Life Radio Map of the United States Including Principal Stations in Canada, Cuba and Porto Rico and Mexico Cit, Mexico." printed in dark blue.
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