Wireless Frequency Help Guide

Answers to commonly asked questions about Shure wireless system selection and set-up.

What frequencies are used for Shure Wireless Products in the U.S.?
Shure wireless systems in the U.S. operate on various unused frequencies within the broadcast television spectrum. Our VHF systems utilized TV channels 7 through 13 (174 - 216 MHz). Shure UHF systems range across TV channels 14 through 69 (470 - 806 MHz). Obviously, fixed channel systems operate on a single frequency, while frequency-agile systems are selectable across a range of frequencies. Specific frequency information for each Shure system is available on our Wireless Frequency Finder.

How do TV stations figure into frequency selection?
Wireless systems should NOT be operated on the same frequency as a local TV station. Only open (unoccupied) frequencies should be used. In the U.S., each major city has different local TV stations. The operating frequencies of those stations must be avoided when choosing a wireless system frequency.

I keep hearing that DTV stations are a big problem. Is that true?
Digital television stations (DTV) represent a wireless interference problem just like any other broadcast signal. They are a major source of interference on the frequencies being used and, depending on the city you're in, local DTV stations may be on the same frequencies as your wireless system. Another factor is that any new broadcast station contributes to "frequency crowding".

Will DTV make my wireless system obsolete?
Like everything else with wireless, the answer is simple: it depends on the frequency. Proper planning makes it relatively easy to avoid problems, both now and in the future. With a frequency-agile wireless system, it's a simple matter to avoid local broadcast TV frequencies (both analog and DTV) by simply changing channels. With a single-frequency system, it's more important to choose frequencies known to be clear, both now and in the future. Again, see our Wireless Frequency Finder.

Shure lists DTV stations that don't exist in my area. Why?
Our lists of recommended frequency codes take future DTV stations into account. Avoiding these trouble spots now lowers the risk of interference problems in the future. Even if a listed DTV station is not currently active, it may be in the process of planning, construction, or preliminary testing.

Is there more to it than that?
Unfortunately, yes. While broadcast signals represent the greatest threat of interference, there can also be interference from cellular phones, taxis, and other band members.

Sounds complicated. Is there a strategy?
Probably the best way to avoid interference is to invest in a "frequency-agile" wireless system. That means the user can change frequencies when interference is encountered. Virtually all touring groups use frequency-agile systems, since their wireless environment changes as they move from town to town.

I'm in a touring band. How do I choose a wireless system?
You are a prime candidate for a "frequency-agile" wireless system. All of Shure's current wireless systems are frequency-agile.

What if I only play in my home town?
In this situation, the TV interference "landscape" is unlikely to change. Most retailers make it a point to sell wireless that is consistently interference-free within the local area. Most local Shure dealers are a great source of frequencies that are reliably free of interference from local television stations.

I'm still not sure what to do. Can I get help?
For purchase decisions, Shure can recommend open frequencies on which to operate in your location(s). For tour planning, multiple frequency lists can be created. For help with this, contact Shure Applications Engineering.

How do I avoid TV interference?
The only dependable way to avoid TV station interference is to know and avoid the frequency bands occupied by local stations. Again, see our Wireless Frequency Finder.

What about interference from other wireless systems?
In addition to avoiding local TV stations, it is essential to select compatible frequencies - ones that do not cause interference with each other. When used together, every wireless system must operate on a different frequency, and these frequencies must be compatible with each other. Compatibility depends on the technical specifications of the systems, and the mathematical relationships between frequencies as they interact with each other.

Does it matter how many systems are being used?
As you add more wireless systems to your stage, the potential for system-to-system interference grows. Every time you add another system, you should check to make sure the new one is compatible with all the others.

Is there an easy way to pick frequencies?
All Shure wireless systems have all been designed with pre-determined groups of compatible frequencies. Charts of compatible frequencies for each Shure wireless system are provided on this Web site as Adobe Acrobat (PDF) files. Each two-letter Shure frequency code in those files are cross-referenced to a particular frequency listed in the compatibility charts. The compatibility charts also list the TV channel number corresponding to that frequency. Keep those frequency codes handy for use when choosing additional systems.

Can I combine Shure wireless with other brands?
Of course you can. The only problem is that each brand chooses their frequencies differently, making frequency selection more difficult. As always, Shure can help. Provide us with the brand, model, and frequencies of any non-Shure systems, and we can recommend the right Shure system and frequency for your next purchase. Just contact Shure Applications Engineering. Or, better yet, stick to using all Shure systems.