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APWPT microphone frequency information

Licensed and Unlicensed Operation Permitted

It is permissible to operate wireless microphones and in ear monitoring systems on either a licensed or unlicensed basis in several bands. In the television broadcasting bands, a power limit of 50 mW applies for unlicensed operation; licensed microphones and in ear monitor transmitters may operate with up to 250 mW.

Wireless microphones may operate on locally unused television channels within the VHF and UHF television broadcasting bands between 54-72, 76-88, 174-216, and 470-698 MHz. Locally unused television channels may be determined by consulting one of the wireless microphone manufacturers’ online frequency finders, or the web site of one of the FCC approved database operators. Currently, the first locally unused television channel above and below UHF channel 37 is reserved for use by wireless microphones, but these reserved channels are being eliminated by the FCC.

Licensed users may register channels they intend to use with one of the FCC approved database operators to receive interference protection from White Space Devices operating in the TV bands. In the future, unlicensed users will no longer be able to register with a database. The FCC made this decision because they expanded licensing eligibility.

In addition to the television bands, wireless microphones can also operate in one of the license-exempt (ISM) bands at 902 - 928 MHz, 2400 - 2483.5 MHz, or 5725 -5850 MHz as well as the UPCS (DECT) band at 1920 - 1930 MHz. Microphones operating in these bands have different technical requirements than those for use in the television bands. These bands are shared with other devices, and can be congested at certain times and places.

The situation for wireless microphone operation in the U.S. is currently in flux due to the upcoming Incentive Auction of UHF (600 MHz) television band frequencies, which is planned to start on 29 March, 2016. Much less UHF spectrum is expected to be available after the upper part of the TV broadcast band is “repurposed”. However, the FCC intends to permit wireless microphones to operate in portions of the new duplex gap and guard bands that will be created as a result of the auction. In addition, additional spectrum will become available in the 900 MHz, 1.5 GHz, and 7 GHz ranges for licensed users. Technical standards and operating requirements are currently being developed for operation in these bands. Further decisions on these matters are expected later in 2016.

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One can download this information here: Frequencies for wireless microphones [1.129 KB]

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Below, you will find a chart showing various possible auction scenarios and the resulting plan for the upper part of the 600 MHz UHF television band:

In the unique case in which exactly 84 MHz of spectrum is cleared, Channel 37 will serve as the lower guard band with a 3 MHz buffer on the upper side to protect the mobile downlink band. Wireless microphones will be permitted to operate in the 2 MHz closest to Channel 37, leaving a 1 MHz buffer to protect the mobile downlink band. White Space Devices will not be permitted to operate in this guard band but they will be allowed to operate in Channel 37. If the auctioned spectrum extends below Channel 37, there will be a second guard band on the lower side which wireless microphones will also be able to use. See the chart below for a clarification of this situation:

In addition to the Duplex Gap and the Guard Bands in the repurposed UHF spectrum, wireless microphones will still be able to operate in any locally unused TV channels. The FCC has stated that it intends to ensure that there will be at least one and possibly two locally unused channels in each market. Licensed wireless microphone users may register channels they intend to use with one of the FCC approved database operators to receive interference protection from White Space Devices operating in the TV bands. In general, unlicensed users are not protected from WSD interference. Under certain circumstances, unlicensed users can still register with a database, but must do so at least 30 days in advance. Following the Incentive Auction, the FCC intends to remove this provision because of the fact that licensing eligibility has been expanded. Entities that regularly use 50 or more wireless microphones, in-ear monitoring systems, or other audio PMSE devices in their productions are now eligible to apply for a Part 74 FCC license.

A new provision in the FCC wireless microphone rules will permit co-channel operation with TV channels in locations where the received signal strength is below -84 dBm. This can be useful in indoor venues where the TV signal is too weak to be receivable.

In addition to the spectrum available in the television bands, wireless microphones can also operate in one of the license-exempt (ISM) bands at 902 - 928 MHz, 2400 - 2483.5 MHz, or 5725 - 5850 MHz as well as the UPCS (DECT) band at 1920 - 1930 MHz. Microphones operating in these bands have different technical requirements than those for use in the television bands. These bands are shared with many other devices, and can be congested at certain times and places, but they can be useful for semi-professional applications.

Because the amount of spectrum available for wireless microphones in the television bands will be reduced after the Incentive Auction, the FCC is making additional spectrum available in several bands. These include the following:

In the VHF band, the FCC will allocate four new frequencies in the 169-172 MHz VHF band at 169.475, 170.275, 171.075, and 171.875 MHz. These frequencies will have the same 200 kHz bandwidth as the TV band frequencies. Output power will be limited to 50 mW. A separate Part 90 FCC license will be required to use these frequencies. Anyone may apply for a Part 90 license.

The 944-952 MHz band will be expanded to include 941.5-952.0, 952.85-956.25, and 956.45-959.85 MHz. This represents an addition of 9.3 MHz to the existing 8 MHz band for a total of 17.3 MHz. Users must hold a Part 74 FCC license in order to operate in this band. In addition, advance coordination with SBE frequency coordinators will be required. Maximum power in this band will be 1W.

The 1435-1525 MHz aeronautical flight test band will be opened for professional wireless microphone operation on a secondary basis. A maximum of 30 MHz will be available for wireless microphone use at a given location. Advance coordination with the Aerospace and Flight Test Radio Coordinating Committee (AFTRCC) will be mandatory. Industry representatives are working with AFTRCC and the FCC to develop equipment requirements and access protocols. The maximum power permitted will be 250 mW.

The 6875-6900 and 7100-7125 MHz bands will become available for professional wireless microphone operation on a secondary basis. Users must hold a Part 74 FCC license in order to operate in this band. In addition, advance coordination with SBE frequency coordinators will be required. Maximum power in this band will be 1W.

The information in this section represents a snapshot of the situation as of November 2015. It will be updated as new information becomes available

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One can download this information here: Frequencies for wireless microphones [1.129 KB]

National government address

Regulatory Body:

Federal Communications Commission
445 12th Street, SW
Washington, DC 20554

http://www.fcc.gov/

Federal Government Spectrum Use Reports

On April 11, 2014 the National Telecommunications and Information Administration (NTIA) published a compendium of detailed narratives describing federal spectrum uses from 225 MHz to 5 GHz.

Link to the NTIA homepage:
Federal Government Spectrum Use Reports 225 MHz to 5 GHz

Freeing 500 MHz spectrum


Now published: (March 2012)

National Broadband Plan / Download the plan / National Frequency Allocation Table
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(17th February 2011)

The USA administration will free 500 MHz of radio spectrum for 4G networks.

Where does it come from?

1) 210 MHz in the TV Broadcast Band

2) 90 MHz in the MSS Band

3) 300 MHz above 3.7 GHz

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Clearing 500 MHz spectrum
(17th February 2011)

FCC have published the "Broadband Infrastructure Policy for the 21st Century"
(10th March 2010)

"
The broadband networks of the 21st century frequently depend upon the policies that government has for infrastructure that is decidedly 20th century—wooden utility poles, conduits underneath bridges, and easements alongside America’s roads and highways. Because government controls and regulates many of these infrastructure inputs, there is a tremendous opportunity for enlightened public policy to spur and accelerate broadband deployment. The draft Plan makes several recommendations that build upon successful efforts undertaken by state and local governments with regard to these important assets.
"

Find the FCC topic WEB page here