FCC Concerns
Written by Tony Stillman Flying Site Assistance Column As seen in the April 2017 issue of Model Aviation.
Hello again! By the time you read this, things should be starting to warm up here—with expectations of getting my new F8F Bearcat in the air! I had an online conversation with an AMA member who wanted AMA to explain how the Federal Communications Commission (FCC) is involved with RC model aircraft. Actually, there are several areas of our RC modeling that the FCC monitors and regulates.
Radio Frequencies
The area that most are familiar with is the frequencies that our RC systems use. AMA has been involved with the FCC and our need for frequencies for many, many years! Just a few years ago, RC was flown on frequencies other than the current 2.4 GHz spread spectrum systems. In the early days of RC, you could only fly on 50-53 MHz Amateur Band equipment, which required an FCC Technician Class license to operate. Later on, Citizen’s Band radio was created and we were able to use 27 MHz frequencies as well. In the late 1960s, we added 72 MHz for aircraft only and 75 MHz for RC cars and boats. Specific frequencies within these bands were referred to as channels. Modelers with an FCC Technician Class (or higher) license were the only ones able to use this specific frequency band (50 to 53 MHz) to remotely control a model. If two modelers tried to operate on the same frequency at the same time, interference would occur, with an inevitable crash to follow! Although these frequencies are still available today, 2.4 GHz spread spectrum has proven to be a more reliable way to fly without concerns of interference from other modelers. There are other radio bands that amateur radio operators can use, depending on their level of licensing. Amateurs are allocated 26 bands (e.g., specific groups of frequencies) spaced from 1.8 MHz, which is just above the broadcast radio frequencies, all the way up to 275 GHz. Most of the frequencies are not for radio control of devices, but are used for communications.This is a Spectrum Ultra Micro FPV Camera and Transmitter—no FCC license is required.
Special-Use Licenses
In the world of FPV model flying, the use of a video transmitter mounted on the model to transmit a video signal from the camera to a monitor or set of goggles can be done on several frequencies. However, the use of certain frequencies at certain power levels requires an FCC license. Typical model use today would be in the areas of FPV drone or fixed-wing racing. A commonly used frequency is 5.8 GHz. In order for an unlicensed person to use this frequency band, the FCC only allows specific power output maximum levels. In this case, they use a complex calculation based on the measured output of the device from a specific distance away. If the device falls below a certain threshold, the FCC requires an FCC identification number on the device itself. This marking indicates that the transmitter can be legally operated without a FCC license. These items have been tested and determined to have low enough power levels, and a fixed antenna as part of their design, so that they will not be an interference threat to other users. Typically these will be 25 milliwatts (mW) of power or less, but the actual determination process is complicated. However, if the item’s output power is above this level or the antenna is replaceable, there will not be an FCC identification number on the product, and it will require the proper FCC licensing to operate. Part of the complexity is that the item can have its power output increased by the use of different antennas attached to it. Antenna designs can increase or decrease the measured output of a device, known as “gain.” This increase in power is measured in decibels or dB. Because of this, most radio frequency units used in today’s FPV aircraft for transmitting a video signal will require the operator to have an FCC Technicians Class license. This is because of its higher level of power output, and also because the design of the unit allows for a screw-on antenna that can be switched out for different designs that have more power or gain. The FCC determined that, because users can influence the output of the device this way, they need to have some knowledge about what interference could be caused unintentionally to other users by making, among other things, an antenna change. Hence the need for the license.ImmersionRC RaceBand 600mW, 5.8 GHz, 15-Channel A/V Transmitter—FCC License required.
So, what have we learned? 1) In order to operate an RC transmitter on 50 to 53 MHz, you must have an FCC Technicians Class license. 2) If you use a video transmitter on 5.8 GHz and operate an RC vehicle (such as FPV) you must verify that it has an FCC ID sticker on the video transmitter unit itself, or have an FCC Technicians Class license in order to operate it. What do you do if you don’t have a license and want to get one? The American Radio Relay League (ARRL) conducts classes to prepare students for and to administer the tests for FCC licenses. You can go to the organization’s website at www.arrl.org and click on “Get your license” to learn about costs and classes in your area. Classes are run by local chapters of the ARRL and are inexpensive. When I took my class, the cost was roughly $35, which included a textbook for study. If you are interested in FPV, this is a must-have to be legal. I hope this helps you to better understand the requirements under US law to use these specific pieces of equipment. -Tony Stillman [email protected]
10 comments
"Do you need an FCC license?"
License for 5.8 Ghz video transmission? When did this happen?
Incorrect frequencies mentioned in article.
There's value in getting a Tech license, and it's easy!
Thanks you for this update.
FPV FCC License
FCC/HAM License
Ham License Requirement
FCC License
Not just Technician's license
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