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UHF Radio Requirements

The FCC has assigned parts of the UHF band for public and emergency use. Some of the frequencies are available for unlicensed broadcast, while some are reserved for emergency services. The frequency's radio waves travel in a straight line so that only line-of-sight transmissions are possible. This limits the distances for which UHF radio is effective. Operation is similar to CB radio, but the higher frequency makes transmission quality better because it is more immune to interference.

Unlicensed
- You can purchase radios for the UHF public band without obtaining a license if you buy radios that are FCC-approved for unlicensed use on UHF. These radios have a transmission power of 0.5 watts or less, and a limited number of channels. Only one radio can transmit at any one time; the rest of the radios within range must listen. These radios are only suitable for very short range communication because of their low power. A typical range is about one mile.
Licensed
- The FCC requires a license for UHF radios with power greater than 0.5 watts. To obtain a license, you have to file FCC form 605 and apply for the General Mobile Radio Service. To qualify, you must be over 18 years of age, certify that you do not represent a foreign government, that construction of your base station will not have a significant effect on the environment and that you will comply with FCC rules and regulations. If you work for a government agency, you may be exempt from paying a fee. Otherwise you will have to submit the fee with the application. At the time of publication the fee is $85.
Operating Requirements
- Because there may be many UHF radios in range at a particular location and on your chosen channel, and because only one can send at a time, you should normally try to block the frequency as little as possible and communicate in a brief, efficient manner. Ideally, once you press the send key, you identify yourself and the person you are trying to reach. You then send a brief message and listen for any response. Be aware that strangers may be able to hear everything you say.
Narrowbanding
- The FCC has allocated a 25 kHz bandwidth for radio channels operating in the UHF frequency band. January 1, 2013 is the schedule date for the FCC to reduce the available bandwidth per channel to 12.5 kHz in an initiative the FCC calls "narrowbanding." This change allows more channels, reduces congestion and supports more users. The 12.5 kHz technology is already available. New licensees should consider purchasing the 12.5 kHz models because the previous bandwidth is obsolete.

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