Some W10 stations were found
At US Television Chronology URL:
http://members.aol.com/jeff560/chronotv.html

Quote
May 31, 1930. Radio Service Bulletin lists these new stations: W10XAL United
States (portable) (National Broadcasting Co.), 2.392 MHz, 50 watts; W10XAO
United States (portable) (National Broadcasting Co.), 1.584 MHz, 50 watts.

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