1. Understanding our Wireless World
Your guide to a successful sports broadcast season by
Ralph Beaver
SBE frequency coordination chair
Understanding our wireless world is a PowerPoint presentation prepared by Ralph Beaver.

2. An RF “channel” is like a blank sheet of paper
An RF “channel” is like a blank sheet of paper. The channel itself is not that special… depends on what you do with it.
If you gave me a blank sheet of paper and said “draw something”, you may get something…
“Channels” or “frequencies”, are like a blank sheet of paper. The channels are used for many different things. One person may use a channel for a wireless microphone. Another may use it for a wireless coach intercom. A TV station or film company may use it for wireless camera control or to fly an indoor blimp.
A channel is a space for you to create something. If you hand a blank sheet of paper and a pencil to me and say “put something on here”, you may get…

3. I cannot draw. This is what you may get.
I can’t draw. I like to joke. This is what I would put of the sheet of paper. You may now throw it away.
BUT if you hand this same sheet of paper and pencil to my daughter and ask that she put something on it, you may get…
…like this!
I cannot draw. This is what you may get.
But if you give this same sheet of paper to a friend of mine, you may get…

4. It’s the same sheet of paper. It’s the same pencil.
…this!
It’s the same sheet of paper. It’s the same pencil.
It just depends on how you use it.
…this! Suitable for framing!
Remember…. It’s the same sheet of paper. It’s the same pencil. It all depends on what you do with it.
Wireless channels can be used for a variety of things.

5. Channel uses IFB Camera Data Broadcast Audio
Operational Communications
Broadcasters may use a wireless channel for IFB (Interrupted Fold Back). That is the audio in the earpiece used by on-air talent.
This same channel could be used as a link between the camera and sound recorder to synchronize them later as footage is being edited.
This same channel could be used as a wireless microphone to pick up crowd noise or to connect the roving talent to the studio or camera.
This same channel could be used for coach communication… but only ONE of the above uses is allowed at one time! If two users try to use the same channel, nobody will have success.
That is what makes frequency coordination critical and necessary.

6. Where Do We Get Wireless Mic Channels?
Reuse existing TV channels -
Where do we get these channels for all these new wireless devices?
Well, pretty much just re-used TV channels. Our federal government has decided to allow wireless devices use in UNOCCUPIED TV channels. If you are within 75 miles of a broadcast TV station, you may NOT use their channel for other wireless devices.
Currently available wireless microphone equipment reuses TV channels not currently in use in your area.

7. Or 10 wireless microphones
1 Television Channel
Or 10 wireless microphones
TV channels are much larger than wireless device channels. How many wireless devices can you use in a single TV channel?
Ten.
This is according to a filing with the Federal Communications Commission (FCC) by Vega communications. This is a general statement and the exact number of wireless devices per TV channel can vary up or down.
This is another reason ‘frequency coordination’ is necessary and helpful. All wireless devices do NOT occupy the same “bandwidth” and they need protection from each other. Exactly ‘how much’ protection depends on the device. It is best to consult someone who ‘speaks the language’ of wireless devices.

8. Over-the-air broadcast channels2 13 14
Let’s take a look at the evolution of the broadcast TV spectrum. In the start (at least for this presentation) we had channel 2 thru 83. These are ‘over the air’ broadcast channels… not ‘cable’ channels. 83
You may remember the typical line of TV channels. Channel 2 through 13 represent the VHF band and 14 thru 83 represent the UHF band.

9. A map such as this one by Shure helps you choose available channels in your area to avoid conflict with broadcast TV stations on the air.
If you visit a web site of a microphone manufacturer (in this case Shure), there are maps of the USA which show the areas you are allowed to operate your microphones.
Notice if you have a wireless microphone on TV channel 11, it would be OK to operate that microphone in Tampa where there is no TV channel 11, but not in Ft. Myers where there IS a TV channel 11.
It’s like a huge jigsaw puzzle.

10. Over-the-air broadcast channels
Back to our TV channel chart…
This is a typical TV market. It happens to be Tampa, Florida since that is where I live and I am familiar with it.
Each green box is an active TV channel in the Tampa TV market. We have a channel 3, 8, 10, 13, 16 and so on.
The top row on this chart (channels 2-13) operate at a power of 300 thousand watts or more. A typical wireless device operates at about one tenth of one watt. The TV station normally wins this spectrum ‘fight’!
This is a sample of the Tampa, Florida TV usage. Each full power TV station is represented by a green box. We have stations on channels 3, 8, 10, 13, 16 and so on.

11. Government re-farming of TV channels
Our federal government has decided to take back TV channels previously allocated to public use broadcast TV, and sell the use of these channel to others.
You will notice the gray boxes at the bottom of the chart representing TV channels This space is re-allocated for cellular telephone use. (Ever wonder where they got all those channels for NexTel, Cingular, Sprint and so on?)
TV channel 37 was also taken back and is used for astrological functions.
YOU MAY NOT USE ANY WIRELESS DEVICES IN THESE GRAY BOXES. They are sold to other companies and the government has promised to protect these channels for them.
Then we consider the TV channels the FCC has re-assigned for “non-TV” use. Your cell phone may be operating in one of these gray boxes!

12. Add low power TV channels
But wait… there’s less!
Low power TV stations (LPTV) were added to the chart and things are getting more crowded. The LPTV stations are indicated by the blue boxes. These are ACTUAL examples in the ACTUAL market of Tampa.
You may only use wireless devices in spectrum represented by the white boxes.
We will add blue boxes to represent Tampa Bay Area low power TV stations. As you can see, the available wireless mic channels are less and less. BUT WAIT!

13. Add digital television channels
But wait… there’s less!
Digital television is added. During the transition of analog (normal) TV to digital TV (HDTV), each broadcast station holding an FCC license for a green box gets a red box also. This allows the TV station to transmit both normal and digital at the same time for a few years until Americans buy the digital TV sets. 5 years is the current guess. It could be longer.
The number of white boxes (the space to use your wireless devices) is shrinking.
Everyone with a green box (analog TV) gets a red box (digital TV). Not many white boxes left for wireless mic use.

14. What is left for wireless use
I have removed the colored boxes in this picture to show the available “boxes” when wireless devices may operate.
Since there are very few devices operating in the channel 2-13 band, I shall remove those boxes.
Removing all the occupied boxes, here are the available channels for wireless. Since most currently available equipment operates on UHF, we will remove the VHF boxes.

15. What is left for wireless use
Before you think “Cool! That looks like a lot”, local broadcasters already use 180 of these channels for their wireless devices.
We must share.
This act of sharing is called ‘frequency coordination’.
Still looks like a lot of room! Right? Nope. Let’s look at a chart published by Lectrosonics to tune their wireless devices.

16. When you buy a ‘frequency agile’ wireless device, you are generally provided with a chart like this.
This particular chart was supplied by Lectrosonics for use with their line of wireless devices.
“Frequency agile” means you can change the channels. This device can tune to 256 different channels. Let’s blow this picture up so we can get a better look.
Notice that a single wireless mic can only tune about 5 TV channels. . .not the entire TV band. Let’s enlarge the bottom chart.

17. This is ‘block 21’ which includes parts of TV channels 25-29
This is ‘block 21’ which includes parts of TV channels There are 256 channels in this list.
That is very misleading.
As you can see by the shading, 5 TV channels are in this chart. Let’s pick a channel.

18. Let’s say you want to operate on this channel
Let’s say you want to operate on this channel. I have highlighted it in green for better understanding. It would appear there are 255 other channels for other people to use, and you will be safe on this one.
Wrong.
There! The green box is your channel. The “other people” can use the remaining 255 channels. WRONG! Your “center frequency” may be the green box, but your “bandwidth” is wider.

19. Only the ‘center’ of your channel occupies one box
Only the ‘center’ of your channel occupies one box. Your actual operating channel is much fatter. I have drawn the actual channel use with the yellow boxes. As you can see, you actually occupy eleven boxes or more… AND you do NOT want other wireless devices in an adjacent box. You need to leave blank boxes between you and the next user.
Just like cars on the highway. You need a little space between the cars to prevent bumping. You need a little space between channels to prevent interference.
Your bandwidth (in yellow) now takes up far more than one box. Let’s compare this chart to our first charts of TV usage. The red box here---

20. Block 21 Wireless Microphone
Back to our white boxes for a moment, the area circled in red is the same as the red box around the 256 channels listed for your new wireless microphone in previous pictures. It includes the ‘block 21’ example of TV channels 25,26,27,28, and 29.
In the Tampa TV market, only channel 27 is available for wireless device use. The would be the white box in the center of the red box. All the others in this block have active TV stations on them and must not be used.
---is the same as the red box here. Oops. Looks like we can only operate in a single TV channel in this market. This reduces your choices to 10 or less.

21. Who do I contact? Manufacturer? Stadium/arena? Local TV Stations?
Local radio stations?
Local cable systems?
Who do I contact to find out which TV channels are OK for use?
The manufacturer? Nope. They give you the chart but they have no way of knowing where you arte going to travel with your wireless device.
The Stadium/arena? Nope. They can tell you a lot of things… like parking, how the concessions stands are run, where the carpet is stored… but TV channel usage is not in their field of expertise.
The local TV stations? Radio stations? Cable systems? Maybe, but not usually.
Your best place to go for this type of information is…
How do you find out who to contact to see which channels are available in any US market?

22. Society of Broadcast Engineers
When you visit the web site, you will find…

23. CLICK HERE
…the frequency coordination section.
Click on that and…

24. … you will see “CLICK HERE for wireless…”
Click it…

25. You then will have every SBE frequency coordinator in the nation and how to contact them.
We have found to be the best contact method since it allows time-shifting of response to accommodate varying work schedules and time zone changes. Other methods are listed.
SBE frequency coordinators are volunteers and are normally employed by a local broadcast station or allied business. They speak the language. They know which channels are OK and which will not work for you.
This is the coordinator list for the entire USA divided by state then city. It will give you names and contact numbers for each TV market.

26. SBE Coordination Program
Started in 1982
Over 200 coordinators
Over 18,000 users!
Volunteer program
The SBE frequency coordination program (above)

27. SBE coordinators are NOT the Police!
The FCC (part of the federal government) polices the use of wireless devices.
SBE frequency coordinators *coordinate* so all users will have success.
SBE frequency coordinators are NOT the police!

28. NFL users of wireless NFL Coach-to-Coach NFL Coach-to-Quarterback
NFL Coach-to-Referee
NFL Replay Booth-to-Referee
NFL Green Hat
NFL Team operations
Food, Traffic, Security, Tickets, Cheerleaders, Stadium AV…
Some examples of NFL wireless device use.

29. Typical NFL Gameday 142 Local B’cst 64 Coach's 33 Network TV
33 Network Radio
27 NFL
17 Local Team
14 Stadium Operations
12 Visiting Radio
10 Visiting TV
10 Stadium AV
10 Food Service
9 Security
8 Film Crews
4 CQB
3 Cleanup
On a typical NFL game day, almost 300 different channels are tracked and coordinated.

30. How the NFL cured the problem
Jay Gerber of the NFL researched the problem…

31. Synergistic Success!
…and decided to embrace the efforts of the SBE.

32. The NFL also supplies these signs which are posted around the stadium on game day.
The NFL also supports the GDC effort with seats in the press box, parking pass, shirts, jackets, hats, computer, radios and any other items which will make this operation work better for the NFL.
These signs are posted in each NFL stadium in areas the media occupies.

33. Exempt from Coordination
Cellular Telephones & PCS
Family Radio Service
Amateur Radio
Trunking Systems
Cellular phones are electronically coordinated by their operating company. Each time you turn on your cell phone, the channel you will transmit on is electronically coordinated your local provider. The power level is also electronically coordinated by the provider.
Family Radio Service radios are just for that... Family communications. They do not operate on frequencies used by broadcasters.
Amateur Radio is self coordinated. They do not operate on frequencies used by broadcasters.
Trunking systems are electronically coordinated much like cell phones.
These categories are not the concern of the SBE frequency coordinator.
These items are “pre-coordinated” by their nature or (in the case of Family Radio Service) cannot be coordinated.

34. Double check of assigned frequency to be sure!
This wireless microphone is operating at That would be in TV channel 45.

35. marked “cleared” units
Brightly colored tags
marked “cleared” units
Each transmitter is tagged to identify checked devices.

36. CONGRATULATIONS! Now you understand our Wireless World
Understanding our wireless world is a PowerPoint presentation prepared by Ralph Beaver.
Have a successful sports broadcast season!