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Compiled by the ARRL Laboratory Staff
Welcome to the first installment of the ARRL RFI Update column, a new feature on ARRLWeb. Here is where you will find the latest news from the world of RFI and learn of the work of the ARRL headquarters staff and RFI Task Group. Future columns will discuss current RFI issues facing ham radio today, interesting cases that the ARRL has handled over the past month and tips on curing your RFI problems.
This month we will describe the resources the League has assembled to help hams deal with the RFI monster. We'll also introduce you to the members of the ARRL HQ RFI Team.
The ARRL RFI Book
Every ham who has an RFI problem needs a copy of The ARRL RFI Book. Experts in the various aspects of RFI affecting hams wrote the book. It starts with the real basics--how to deal with the interpersonal aspects of RFI. (Knowing all the technical solutions will do no good if your neighbor won't let you in the house to try them!) Chapters cover the topics of Electromagnetic Compatibility Theory as it relates to transmitters, televisions, cable television, telephones, audio devices, computer and automotive RFI. Income from sales of The RFI Book helps pay for ARRL's RFI programs. Order your copy today.
The ARRL RFI Web Pages
As a service to Amateur Radio, ARRL has written a series of Web pages that offer fast information for the ham who is having an RFI problem. If that sounds like you, order The RFI Book, and then consult the League's RFI Web pages. These pages are available to everyone--member or not. While not as thorough as The RFI Book, the RFI page is a great place to start.
The RFI Home Page on ARRLWeb
The RFI Home Page is the place to begin, not only because of the quick introduction it provides, but because it contains links to other pages dealing with interference to specific kinds of devices. Clicking on a link may take you to a discussion of the causes and cures for that specific type of RFI, or it may simply contain other links--sometimes to reprints of QST or other articles. Some pages contain links to Web sites external to the ARRL site.
The RFI Home Page provides an overview of RFI issues from political and technical points of view. It discusses how to handle the situation if an unhappy second party is involved (perhaps your neighbor). The page will give you a sense that the problem is not insurmountable and will help put the issues into perspective for you.
The page also takes a look at ways to diagnose and correct RFI problems. One section lists sources for information and equipment that will help you deal with RFI.
Other RFI Pages on ARRLWeb
Information for the Neighbors of Hams --This is the page to read before you talk to your neighbor about an RFI problem. The pamphlet, published jointly by the ARRL and the Consumer Electronics Association, explains the complex RFI problem in terms that non-technical people can understand. If you ever find yourself dealing with an irate neighbor, one of the best things you can do is give them a copy of this page. It will help your neighbor understand that there can be many causes of interference other than your transmitter. Even if they are indeed hearing you, it may not be the fault of your station. This little document has opened the eyes of many an unhappy neighbor.
FCC RFI Information--This page explains that the FCC believes that most interference is not caused by rules violations at the station. Print the FCC information and show it to your neighbor to help them understand why your role is not to be a provider of solutions, but instead, a finder of solutions. As a good neighbor, you want to help them find a solution to the interference at their house.
Television Interference --This page covers the ABCs of TVI, from neighborly relations to the rules about spurious emissions, to the use of low-pass filters, high-pass filters and common-mode chokes to chase the TVI gremlins.
Cable Television Interference --CATVI is featured on a page separate from the TVI page because the cures that work for over-the-air television interference may not work for cable-TV interference. This page has a link to a three-part article written by W1RFI for Communications Technology, the journal of the Society of Cable Telecommunications Engineers. Hare wrote the article for CT in part because ARRL wanted an article that hams could print and show to their cable operator.
Telephone Interference --When telephones and other non-radio devices pick up nearby radio signals, the FCC says the devices are improperly functioning as radio receivers. This page explains how to troubleshoot telephone systems and apply the correct cures to telephones and telephone devices.
Intermodulation --Most hams call any signal that overloads a repeater or VHF FM receiver intermod. This page, an article written by W1RFI, explains the different ways that intermod can occur and offers three different filter techniques to cure it.
Computer Interference --Computers are found in so many products today that the line between computers and radios is becoming less distinct. This overview of computer interference explains how filtering and shielding may help overcome interference to or from computers.
Electrical and Power-Line Interference --This is probably the ham interference problem of the 21st century. When power-line noise interferes with radio services, FCC rules require the power company to correct the problem. This page offers reprints of QST articles on power-line interference and explains the ARRL's cooperative relationship with the FCC and various power companies. A letter from FCC to the offending power company--regarding the uncorrected noise--is also included. Print it and show it to your power company. Hopefully, they will prefer to read the text on ARRLWeb than receive a personal version from the FCC.
Automotive and Ignition Noise --W1RFI's old pickup truck has no factory electronics other than the car radio and ignition system. Today's vehicles can have as many as 60 electronic modules, some of which have several microprocessors. One simply cannot expect today's vehicles to be as electrically quiet as those of days past. This page has links to articles that discuss the various causes and cures of automotive RFI, how to deal with your vehicle manufacturer and how to shop for a car that is ham friendly.
FCC--Part 15 Rules and Regulatory Information Packages--This topic is very much related to power-line, automotive and computer interference. These pages explain in great detail the rules that apply to unlicensed transmitters and to Amateur Radio. Learn why computer devices, switch-mode power supplies and unlicensed transmitters can radiate signals legally in our bands. The Regulatory page explains such important things as federal preemption of local laws about RFI and what to do if the cops show up.
Other pages cover Audio Interference, Electric Fence Interference, Pacemakers and Amateur Radio and Touch Lamp and Dimmer Noise and Interference. Check the RFI Home Page often; the Lab staff is always adding new information. As you will see when you go through the pages, the League's investment of your dues in the RFI area is a valuable membership service.
The ARRL HQ RFI Team
These pages are created and maintained by the RFI team at HQ, in the Laboratory and the Regulatory Information Branch. As you can imagine, their responsibilities extend far beyond just what you see on the Web pages. They answer questions from members, research RFI matters--both technical and regulatory--and provide support to members who have tried their best to solve RFI problems and don't know where to turn next. The RFI Team are the people who will help you to find your way through the electromagnetic jungle. If you're having a problem with RFI, read the Web pages and The RFI Book, then contact the RFI team for help and advice.
 ARRL Laboratory Supervisor Ed Hare, W1RFI |
From a diverse background that includes ownership of a TV/audio repair shop, a computer-aided-design system installer and a component test engineer, Ed came to ARRL HQ in 1986, to be the Lab's Product Review Test Engineer. In answering members' questions on the phones, 12 years ago, Ed realized that there was more to RFI than high-pass filters and ferrites, so he undertook what would grow into a career at ARRL HQ--helping Amateur Radio deal with the many-faceted problems of RFI and Amateur Radio.
Today his influence in the RFI field extends from helping individual hams with problems to his work on the IEEE C.63 EMC standards committees. He also maintains regular contact with industry groups, consumer-equipment and automobile manufacturers and many of the FCC staff. "I really can't imagine doing anything else with my life right now," says Hare. "Working at ARRL HQ, I am given an opportunity to work with hams, industry and the FCC on something that really makes a difference. The RFI problems that plague hams and their neighbors really are a quality of life issue, for all concerned. It feels great that I can do something that makes a real difference to an entire radio service, here in the US and in the world," he says.
On a personal note, Ed is quite a character. He's well known for his sometimes-unusual sense of humor and unexpected antics. Ed is active in the QRP community, although he doesn't get on the air as often as he would like. "I talk to hams all day on the phone and by email. Many days, I want to go home and play with my stamp collection," he notes. But he can be found near the QRP frequencies, operating his favorite mode--CW. He has taken QRP to quite an extreme, having used 10 milliwatts in the ARRL CW Sweepstakes (56 contacts in 34 sections). If you hear him on 40 meters, he is apt to be using the original Tuna Tin 2, built in the ARRL Lab in 1976 by Doug DeMaw. Ed and his wife Suli live in Burlington, Connecticut.
The RFI Update column is published monthly on ARRLWeb. The column features information on current activities in the RFI arena, interesting RFI cases handled by ARRL and tips for solving RFI problems. An archive of past RFI Update columns is available. If you have information you believe is useful to ARRL's RFI program, or if you need help with an interference problem, contact the ARRL RFI team, call the ARRL Laboratory staff at (860) 594-0214 or write to the ARRL RFI Desk, 225 Main St, Newington, CT 06111.
