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FCC Proposes Clearing Wireless Microphones From 700 MHz band

Thursday the FCC released a Notice of Proposed Rulemaking and Order (FCC 08-188) to ban operation of wireless microphones on TV channels 52-69 (698-806 MHz) after the end of the DTV transition at 11:59 p.m., Feb. 17, 2009, and blocking sale or importation, sale, manufacture or shipment of devices operating in this spectrum.

The order imposes a freeze, effective immediately, on the filing of any new license application seeking operation on any frequencies in the 698-806 MHz band after Feb. 17, 2009 and a freeze on any pending equipment authorization for low-power broadcast auxiliary equipment operating in this band.

While FCC records show only 156 out of 943 low power auxiliary broadcast service licenses are authorized to operate in the 700 MHz band, many 700 MHz-band only wireless microphone systems (older Sony UWP models, for example) were sold by retailers to individuals and other non-broadcast users. Since these users are not eligible for a Part 74 license, I suspect hundreds of these units, if not thousands, are in the hands of users that do not have a license for them and who are likely to continue using them past Feb. 17, 2009.

I looked at the Sony wireless microphones available on the BH Photo Video Web site (opens in new tab) and noticed that while many units operating above 698 MHz were listed, all of them were identified as “discontinued”. Obviously these units were available to anyone with a credit card until recently. It appears all currently available units operate on UHF TV channels below 698 MHz.

While broadcasters who hold Part 74 licenses in the 700 MHz band are likely to abide by the FCC’s final decision, the individuals and production companies that purchased wireless microphones capable of operating only in the 700 MHz band are likely to continue using them, to the possible detriment of the new public safety and commercial wireless services using these frequencies post-transition.

This situation is an example of the potential problems lawmakers should consider when deciding whether to allow unlicensed devices in the new TV “white space”.

Doug Lung is one of America's foremost authorities on broadcast RF technology. He has been with NBC since 1985 and is currently vice president of broadcast technology for NBC/Telemundo stations.