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On April 13, 2017, most of the 600MHz frequencies that had been available to wireless microphone manufacturers were auctioned off to, and repurposed for use by, other wireless services. The phased transition of these frequencies from sellers to buyers will occur between April 13, 2017 and July 13, 2020. To obtain the latest information available on which geographical areas are currently affected please reference-
If your area has transitioned, you must not operate wireless microphones on frequencies in the new 600MHz service band (614-698MHz). There are some exceptions in this service band. Please check the FCC website for information on acceptable use in the 600MHz band.