Tips for resolving interference issues

Whether harmful or nuisance, the FCC prefers that licensees sharing channels work together to create an amicable shared environment. If you are hearing one of your neighbors, the FCC wants you to contact that licensee and cooperatively resolve the matter.

The FCC is pretty clear in its rules on the responsibilities of licensees:

"Licensees shall take reasonable precautions to avoid causing harmful interference to other co-channel systems. This includes monitoring the frequency for communications in progress and such other measures as may be necessary to minimize the potential for causing interference." (FCC Rule Section 90.403)

Get to know your neighbors

It’s a good idea to know the entities with which you’re sharing your channel. Knowing this can help you identify potential sources of interference. Also, you can establish a relationship with these entities and create a plan for sharing the channel.

When EWA certifies an application, it gives the applicant a “Co-channel Licensee Report” that identifies incumbent systems and provides the critical, technical information that can help determine the potential for nuisance interference. EWA uses a similar report when it resolves or mediates a case of interference.

Listen

If you hear interference, take down as much information about it as you are able.

What, exactly, are you hearing?

• Voice or digital?
• Can you record an example?
• If you hear the call sign of the transmitting entity, write it down.

This data will help you track down and get in touch with the party potentially causing interference to your radio system. If you have not requested a Co-channel Licensee Report from EWA, when you do so, provide all of the information you’ve gathered to help identify the source more quickly.

With the information you provide, EWA researches all the licensees within a specified area and will evaluate the results, looking for newly granted licenses or recent license modifications to narrow the list of possible suspects. If the results of this evaluation yield potential sources, EWA will provide contact information to you with the results of the co-channel search.

We can work it out

The FCC wants co-channel users to resolve interference issues themselves or through a mediator like EWA, the Association of Public-Safety Communications Officials (APCO) or the Association of American Railroads (AAR). These are the only three entities with which the FCC has established Memorandums of Understanding.

Most of the time, licensees that work together resolve their interference issues successfully. Sometimes, licensees will voluntarily modify their systems to resolve the interference. As you discuss the issue, you may find that the resolution is fairly simple. For example, incorrectly programmed equipment could be the culprit. In fact, contacting your dealer or technician at this stage might prove beneficial.

When should you engage the FCC?

As a mediator working on behalf of the FCC, EWA strives to help licensees resolve their issues and not to merely pass them along to the FCC to fix. In 2014, EWA forwarded to the FCC for action less than 10% of the interference issues it was asked to mediate. However, if the licensee causing the interference does not care to cooperate, is unresponsive or the co-channel search does not yield any results, it’s time to turn to the FCC. 

When forwarding a case for action, EWA sends all of the information it has—including anything gathered by the reporting licensee.

Unfortunately, we don’t always hear from the FCC how the case was resolved.