Eugene Radio Frequency Interference (RFI) Information
The Valley Radio Club is making an effort to assist in tracking down and resolve RFI problems effecting radio communications. Our goal is to work locally with property owners and utility companies to identify and resolve potential RFI issues. Resolving such issues locally benefits all of us.
Unresolved RFI complaints can be referred to the Federal Communications Commission (FCC) for resolution. We firmly believe that resolving issues locally, in an informal manner, is far more desirable than referring issues to the FCC. In the end, it is the FCC that maintains the ultimate regulatory responsibility for addressing RFI issues impacting the proper options of licensed communications services.
What causes RFI?
Many things can cause RFI such as, but not limited to, the items listed below:
- Poorly designed or manufactured consumer electronics which may be in violation of FCC part 15 rules and regulations.
- Loose of poor electrical connections within distribution and building electrical systems.
- Plasma TV’s
- Lighting and lamp Dimmers
- Electric Motors
- Indoor high power grow lighting systems
- Aquarium Heaters
- Door Bell Transformers
- Older Compact Fluorescent Lamps
- Floor Heaters
- Neon Signs
- Electric Fences
- Power Tools
Here is what we do when we have a reported RFI source that is causing interference to licensed station operations:
We first characterize the source by monitoring for a few weeks. We keep careful notes in the event the FCC becomes involved, and we use direction finding equipment to locate what we believe to be the source of the RFI.
Here is what our club does for RFI when we believe we have located a RFI source:
Once we believe we have located a RFI source, we begin a very complete process of documentation. The first thing we do is to insure that the person making the RFI report is not unknowingly the source of the RFI. We will suggest removing power from his/her home, and then using a battery powered radio we listen to see if the RFI continues. If after the power is shut off, the RFI continues, it is a pretty good bet it is not coming from the reporters home. If on the other hand the RFI ceases when the power is shut off, then it is a pretty good bet the RFI source is contained within the reporting persons home. This insures that the reporting person is not the cause of the RFI, as happens in many cases.
Assuming the reporting person wants to continue, the next step is to place RF monitoring equipment at the location where RFI is being experienced. The computer/receiver work together to capture the signal for later analyses. The signal analysis helps in several ways later:
- Helps ID the signal type
- In some cases the device generating the RFI can be identified directly without entering a residence.
Should the person living at a location wish, we will assist in indicating that their location may be causing RFI by providing an outside listening service. i.e. if the person removes the source, we will let you know if we still hear what we believe to be RFI. This is not a scientific test, but in most cases it locates the source quite easily. In some cases it is not correct, but most of the time it is. For legal reasons we will not provide filters, nor will we enter a residence under any circumstances. Nor do we represent this as an overall test for all types of RFI. It is incumbant on the resident to test for RFI, we are simply providing a free service which may not show all RFI.
We may contact the person living at a residence first, or we may contact the property owner of a residence first. We also may just send in a direct complaint to the FCC reporting a possible RFI violation, not contacting anyone. However, our goal is to solve the RFI problem at the local level if possible, but if necessary to escalate up to and including FCC involvement until the issue is resolved.
Who is responsible for a solution to RFI?
In most cases, the person creating the RFI is responsible. If for instance a person has an aquarium and the heater is generating RFI in excess of FCC limits, then the operator of the device is responsible for making sure that the device generating the RFI is operating within within FCC specifications as outlined in Part 15 and Part 18, of the FCC rules.
See this recent enforcement letter from the FCC, sent to a person with horticultural lighting generating RFI.
Who is responsible for enforcement of RFI complaints?
The FCC licenses radio transmission and reception stations in the United States. As part of that responsibility, the FCC is the regulatory agency charged with maintaining the licensed radio frequencies to be free of harmful interference, (RFI).
Such licensed frequencies include, but are not limited to those used by fire, police, cellular phone services, cable TV, amateur radio, as well as commercial radio and television broadcasting. Ultimately, it is the FCC’s responsibility to take enforcement actions against those generating RFI that negatively impacts the authorized users of licensed radio frequencies.
More information about RFI can be found at the following links: