I just read the following on pg. 19 of Greg Heuman's excellent and informative treatise,"ALL ABOUT HARMONICA MICROPHONES AND THEN SOME"(http://blowsmeaway.com/all%20about%20harmonica%20microphones.pdf): Important to users in the United States: Under a new FCC rule, anyone who uses a wireless microphone that operates in the 700 MHz Band, and that means almost every wireless system sold prior to late 2009, must stop operating their wireless micro-phone no later than June 12, 2010. All users of 700 MHz Band wireless microphones (and similar devices)âincluding theaters, churches, schools, conference centers, theme parks, and musiciansâwill need to retune (where possible) or replace their wireless microphone equipment with other microphone devices no later than June 12, 2010. This action helps complete an important component of the DTV Transition by clearing the 700 MHz band to enable the rollout of communications services for public safety and the deployment of next generation 4G wireless devices for consumers. For further information, please visit the website at http://www.fcc.gov/cgb/wirelessmicrophones
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