The Right to Remain Silent: Are your wireless mics illegal?
Are you breaking the law by using your wireless mics?
This is an entirely relevant question in light of recent developments taking place with RF spectrum regulation and allocation.
This is a very dense topic and there is a fair amount of speculation and misinformation out there. Because there are developments happening every day which change the details, it is a challenge to get a hold of the facts. A general understanding of what the issues are should tell you whether your house of worship is directly affected by these changes. You may only need to be aware of a few of the really pertinent points, especially those pertaining to how these changes affect products you may already own.
First of all, wireless microphone products are not going to suddenly stop working, and they are certainly not going to stop working if the DTV transition happens in June of 2009. However, eventually certain products are going to run the risk of picking up interference from other products. This whole issue is based on frequency availability. Ever been driving in your car listening to a great radio station, and then the signal gets stomped on by a stronger signal? It’s the same type of idea.
There are three main issues in this whole subject. That of the Digital TV Transition, the 700 MHz band, and that of White Spaces.
It helps to break these out separately, seeing as part of the overall confusion comes from people making associations between these three topics.
Digital TV Transition
As you probably know, Congress has set June 12th, 2009 as the date to terminate analog broadcasts in the United States. The relevance of this transition in reference to wireless microphones will hopefully become clear as we continue through this article.
The FCC advocates for digital television versus analog, because, well it’s just better. DTV has improved signal characteristics, better picture, better audio, among other advantages. Another reason is that unlike analog, digital TV signals can be broadcast on adjacent channels. In the White Spaces section of this article, we’ll talk a little about why this is important.
The FCC has made a decision to take the 1700 or so TV stations in the United States and realign them on the spectrum chart. The plan was to realign them in such a way so that when they were done with the digital transition, all of the TV stations would be nicely organized.
To tie in the relevance of wireless microphones to this transition, one should be aware that many wireless microphones use the RF spectrum to transmit- the same RF spectrum used by analog as well as digital TV signals. And there is only so much of it available to use.
While this transition is happening, some television stations are transmitting both in analog as well as digital signals, to accommodate viewers in both demographics. A common misconception is that there is an association with wireless microphones not working after the DTV transition. In reality, it’s more likely the opposite, seeing as once the transition happens, all of the analog signals will be taken off the air, which will actually clear up some RF space.
However the DTV transition has started a domino effect as far as people seriously paying attention to the value of RF spectrum. Basically, things aren’t as wide open as they used to be. The DTV transition will nicely organize TV broadcast signals, but there are still many questions as to what will happen to the remaining space freed up by all of the analog transmissions going away.
700 MHz Band
Probably the most highly contested RF area in this process is the 700 MHz band, which lives in the upper end of the UHF TV band, essentially channels 52-69.
Because of the desirable propagation qualities of the 700 MHz range, it has always been an intensely coveted frequency space. Just as beachfront property is aggresively sought-after, so is prime spectrum real estate. So, acting as a pseudo-real estate agent, the FCC held an auction for this frequency range, and chunks of the spectrum were sold to the highest bidder. When all was said and done, the range was eventually divvied up and chunks of it were sold to certain telecommunications companies for an aggregate amount of 19 billion dollars. Yes, that’s billion, with a “b”. The spectrum in this band that was not part of the auction was assigned by the FCC to be used by emergency public services, such as firefighters and ambulances.
The auction and impending allocation of this frequency range have made wireless microphone users aware of a cold, harsh reality: if your house of worship is using wireless devices that operate in the 700 MHz band, (the frequency band between 698 - 806 MHz) you are expected to stop. That means now.
However, that does not mean that products in this frequency range will all of a sudden stop working.
“Functional, 700 MHz wireless mics will continue to work reliably for many months, maybe even years in some parts of the country.” explains Joe Ciaudelli, Marketing Manager for Sennheiser.
However, if you continue transmitting wireless microphone signals in this frequency range, be aware that not only are you running the risk picking up interference from any of the devices these telecommunication companies decide to put online, you are also breaking the law.
“700 MHz needs to be vacated by all other wireless services including microphones, because the new owners obviously want clean spectrum,” states Steve Savanyu, Director, Educational Services for Audio Technica. “Some folks are saying ‘It won’t matter if I use my wireless inside my church, who will know?’ Well, you can also drive 100 MPH down the Ohio Turnpike and you might not get caught by the state trooper, but if you do get caught...”
When the question came up as to why wireless microphone manufacturers didn’t try to buy any of this frequency range, the answer was a matter of dollars. The wireless microphone industry as a whole is not worth billions. Even combined, wireless mic manufacturers did not have the cash to bid on this space. To put it in perspective, even Google was outbid in their offer to buy a chunk of the 700 MHz range.
Essentially, what we know for sure is that this frequency range is off limits to wireless microphone users. What we don’t know is when the FCC will decide to actively start enforcing legal action on the folks who still decide to use it for this purpose.
White Spaces
What confuses many people is the fact that “White Spaces” are separate from the 700 MHz band issue.
Let’s talk a little about the characteristics of an analog TV signal, in simple terms. For those of us old enough to remember, television sets often had two knobs- one for VHF (Very High Frequency), and one for UHF (Ultra High Frequency). The VHF range included channels 2 through 13, and the UHF-TV range comprised Channels 14-69.
Analog TV signals are allotted a 6 GHz wise area to transmit. This 6 GHz wide area represents one channel. Analog TV signals could not be transmitted on two adjacent channels in a given community, ie: channel 3 and 4, because of the characteristics of an analog signal; there was a chance that one channel would interfere with the other. To remedy this, there was space left open on either side of the channel area.
“[White Spaces] are defined as “unused” TV channels in a given locality.” explains Steve Savanyu. “Unused means unoccupied by a TV station. In the old analog days, it was not possible to have TV stations operating on adjacent channels due to the potential for interference. So in a given community (I’ll use VHF channel numbers for simplicity) you might see CBS-Ch2, NBC-Ch4, ABC-Ch6, and in a neighboring community you would see Channels 3, 5, 8.”
However now, these unoccupied channels (referred to as “White Spaces”) are going to be open for TeleVision Band Devices (TVBDs), formerly called White Space Devices. Where wireless microphones were once able to use these white spaces to transmit, now they run the risk of being interfered with by these TVBDs.
As Joe Ciaudelli defines it, “TVBDs [are] a new class of unlicensed consumer equipment that will operate on TV channels that are not being used for TV broadcast or wireless mics.” These will inevitably include portable wireless internet devices, to enable web connectivity even in rural areas. Think Googlephones.
This is where the FCC has made some accommodation for wireless microphone manufacturers and users. TVBDs will have to consistently check a Geolocation database before they can operate on a certain frequency. If the database indicates that there is already a licensed user in that range, the TVBD will have to look for another frequency to use to transmit. This will hopefully prevent your Pastor’s wireless signal from getting stomped on if he/she gets a text message on their TVBD during the sermon.
However, in order for your wireless devices to be found in the database, they will need to be licensed. The process of obtaining licenses for wireless microphones is apparently on the FCC website, but unfortunately the process is slightly arduous. We can only hope that as this issue evolves, the process will be facilitated so that houses of worship can apply for appropriate licenses for their wireless devices, so as to show up on the Geolocation database and not get trampled on by TVBD users.
What can you do?
Do you know what frequency range your wireless mics operate in? If not, you should find out. If it turns out that your wireless mics are in the 700 MHz range, then you should contact your manufacturer to determine your options.
Check manufacturer websites- they should have information available that is readily accessible- plus further links to FCC pages and PDFs that contain more information.
If someone approaches your church and offers to sell you professional grade wireless systems for a great price, make sure it’s not in the 700 MHz range.
Some other solutions? Use wired mics everywhere you can. Try to consolidate your wireless usage so that it is only used when imperative. For example, in most cases, it is NOT necessary to put wireless mics on the drum kit.
“Start by thinking carefully about whether or not wireless mics are really needed in all cases.” suggests Karl Winkler, director of business development at Lectrosonics, Inc. “Can you use wired IEMs instead of wireless? Will a fixed podium mic work as well as a wireless lav?”
“If it doesn’t have to move during the service, wire it down.” adds Steve Savanyu.
Bottom line, things are changing. The entire RF spectrum after the DTV transition is going to be clearer at first, but then will eventually be populated by TVBDs. The 700 MHz range is off limits. Wireless mic users in the US may see a future that is much like the reality that is now being lived in the UK: all wireless users may have to operate with a license.
Keep in mind that there is a very large community of wireless mic users and manufacturers who are working to make sure that the impending transitions are going to be as smooth as possible. Many companies have already put several safeguards in place for wireless users, including product rebates and frequency coordination tools. Manufacturers are also constantly developing new wireless technologies which alleviate RF concerns.
As we change and adapt to the new realities, resources like this publication are going to be available to help answer questions. Wireless technology still has a place in the modern worship service. Just make sure you know what the facts are so that your wireless mics will not have to potentially go silent.
