For the American Radio Relay League Board of Directors Meeting
January 19 and 20, 2001
Submitted by
Dennis Bodson, W4PWF
Chairman, RFI Task Group
REPORT TO THE ARRL BOARD OF DIRECTORS
RFI TASK GROUP?
Date: January 19, 2001
Members of the Committee:
The RFI Task Group recommends that the appointments of the present membership be continued. In addition, the Task Group expects to appoint one or two new members in 2001.
Mission Statement:
The ARRL RFI Task Group monitors developments in the Electromagnetic Compatibility field and assesses their impact on the Amateur Radio Service. The Task Group then informs the ARRL Board of Directors about these activities and makes policy recommendations for further action, if appropriate.
In Person Meeting:
The RFI Task Group held and in-person meeting on November 29, 2000 at the Lucent Technology facility in Allentown, PA. The committee would like to thank Mr Strauss and Lucent technologies for their hospitality. In attendance were Mr Bodson, Mr Boucher, Mr Hare, Dr McConnell, Mr Steffka, Dr Strauss and Mr Turnbull. Messrs Hranac and Stinson were unable to attend.
Mr Bodson started the meeting with a presentation on the overall role of the committee and its goals. He explained to the committee that its roles are:
Mr Turnbull gave a presentation on the role of the RFI Task Group in the past, both before he became committee Chairman and during the time he served in that role in 1980 through 1999. He outlined the committees "watchdog" role with respect to the ANSI C63 committee developing standards for immunity of consumer electronic devices. He also described the role the committee played in ARRL's overall spectrum-management objectives and asked that ARRL consider the best ways to continue to manage amateur spectrum.
Mr Steffka gave a presentation on the General Motors EMC Lab facility. GM is in the process of adding significant new capability to their EMC test lab. He also outlined some of the differences between modern cars and their predecessors, explaining why the day of the backyard mechanic installing simple RFI cures is pretty much over. During the ensuing discussion, the committee concluded that miscommunication between the EMC engineering departments, zone offices, dealers and customers is a major part of automotive EMC problems. The committee concluded that information about Amateur Radio and its unique problems would be valuable to the industry.
Dr Strauss presented information about the Home Phone Networking Alliance (HPNA) industry specification. HPNA networks computers within a residence or business using existing telephone wiring. The HPNA specification includes spectral protection for the present HF international amateur bands within its frequency range of up to 9.5 MHz. Dr Strauss noted that this protection was originally proposed by individuals within HPNA and that ARRL's participation and cooperation was an important part of the committee's decision to offer more protection to the Amateur Radio Service than was required by the radiated emissions limits in Part 15. He gave an overview of Bluetooth, HomeRF and the IEEE 802.11 standard for RF networking. In the ensuing discussion, the HomePlug industry specification was also discussed. HomePlug networks computers using existing residential or business electrical wiring. The present version of the HomePlug specification does include notch protection for the HF ham bands in its frequency range.
Dr McConnell gave an overview of the present state of VDSL standards. The present standard calls for the VDSL signals as high in frequency as 20 MHz to be conducted using utility telephone wiring to neighborhood hubs, which would then link to the provider central office using fiber. Both of the VDSL standards under development call for the use of spectral notches within the international ham bands. Dr. McConnell described how the notches were first proposed within the VDSL committees and that ARRL's participation and liaison was an important part of the decision to make such protection part of the final standards.
Mr Boucher talked about power-line interference problems. RFI problems faced by amateurs and the utility industry are growing. More now than in years past, utilities are not able to resolve power-line noise problems promptly. Deregulation and related mergers and acquisitions are a major factor. Many utilities do not have the staff or financial resources to give power-line noise a high priority. Power outages and actual failures are a high priority, and, at best, noise problems are handled as time is available. In years past, utility companies had experienced staff available to troubleshoot and repair noise problems. This is not as true today. Experienced people have retired or been promoted, leaving a gap in RFI expertise. With most TV viewers using cable or satellite providers, the utilities do not have the volume of complaints that used to drive their ongoing RFI resolution. Miscommunication is also a major part of the problem, starting with the "800" number customer-service agents not knowing about RFI. If the call is properly referred to the service department, they may not have RFI expertise to troubleshoot the problem. If they do have experienced staff, it often takes months to schedule troubleshooting. (Even at that, the level of experience can vary wildly.) Once the problem is identified, if it is coming from utility-owned equipment, the actual repairs must be done by linemen, who generally have even less RFI experience. Even if it gets that far, few utilities follow up with the original complainant to ascertain whether the problem was actually resolved.
The committee concluded that information about utility-related RFI needs to be prepared for the utility company and that, by various means, this information needs to be provided to the utility companies. Mr Boucher and Mr Hare agreed to write an article that will be submitted to the trade journals of the utility industry. The article, possibly in several parts, would outline the customer-communications aspects as well as the major troubleshooting and technical solutions that ARRL feels that utility companies should know. This article, once published, would also be made available on the ARRL Web pages. Printed copies of ARRL's information about power-line RFI could then be mailed to utility companies as needed, either on a case by case basis, or, if funding is available, to the service managers and technical vice presidents of all or most utility companies
Mr Hare then outlined the role of ARRL HQ staff with respect to RFI problems. This role consists of the following:
Messrs Bodson and Hare both pointed out that some of this recommended contact would best be accomplished through volunteer help, such as the work done by Dr. Strauss and Dr. McConnell on their respective committees
The committee discussed the need to prepare and disseminate information packages about RFI, both to hams and to the involved industries. The two main areas that the committee recommended be addressed first were automotive and electrical interference. Mr. Steffka agreed to write an article about automotive interference and Mr. Boucher and Mr Hare agreed to write an article about power line issues. The first step to promoting such information would be to seek publication of these articles in the trade journals of their respective industries. The information could then be turned into ARRL web pages or printed (with permission from the publisher, which is almost certain to be granted), In the case of the automotive RFI information, this could be potentially disseminated to industry through the SAE EMI Standards Committee. In the case of power lines, it may be necessary to send the information to the utility companies by postal mail, assuming such mass mailing could be funded.
The committee also asked that regular updates be done to the ARRL's published RFI materials, both on the Web and its books. Mr. Hare indicated that the web material could be updated as needed and that the ARRL RFI Book could be updated a few months before each printing.
The committee spent considerable time discussing RFI to hams. It concluded that this is a growing problem and that ARRL needs to make addressing it a high priority. The committee recommends that this be discussed with the FCC at the policy level. The Task Group and its staff liaison are prepared to assist by preparing whatever information and documentation are required to assist in doing this.
Part 15 rules have two major requirements: that Part 15 devices not exceed specific emissions limits and that they not cause harmful interference. The maximum emissions limits are unacceptably high (some would result in S9+15 dB signals on some HF bands). The only reason Amateur Radio can live with those limits is because the rules also address harmful interference; the rules require that the operators of Part 15 devices correct harmful interference. The FCC and industry base their rulemaking positions with respect to the emissions limits on the fact that interference is not permitted. It is critical, however, that the FCC be willing to enforce the non-interference clauses in the rules, either in individual cases or in cases where the aggregate of many unidentifiable sources causes a significant increase in noise. In many cases, Part-15-device operators do what the rules require (sometimes after some encouragement from ARRL), but in some cases, they do not. The committee recommends that ARRL identify several cases of actual harmful interference that the Part-15 device operator is not willing to correct and that ARRL seek relief from the FCC in those cases. This will help determine whether the non-interference clauses in the rules offer adequate protection to the Amateur Radio Service. As a minimum, it may offer relief in the specific cases taken to the FCC
The committee also discussed the resources needed to carry out some of these recommendations. It believes that RFI is still a major threat to Amateur Radio and that interference to hams, especially from Part 15 devices, is increasing. The committee recommends that ARRL determine what resources are necessary to continue to have a strong RFI program in this changing environment. It also recommends that ARRL promote its work with RFI within the amateur community, so that the work done by the committee, HQ staff and volunteers will be better known to amateurs and industry alike.
After the meeting, the ARRL RFI Task Group gave a presentation at a nearby meeting of the RF Hill Amateur Radio Club.
Status of Current Projects:
ANSI/IEEE C.63 Committee: The C.63 committee is working on developing industry standards of immunity for consumer devices. ARRL serves as a resource to the committee to protect the interests of Amateur Radio. Subcommittee 1 continues to work on a variety of EMC projects, primarily related to test site standardization. Subcommittee 8 deals with various types of medical equipment. It is important that ARRL be involved with this subcommittee because medical equipment can be used in residential environments.
Mr Turnbull asked that he retire as ARRL's representative on C.63. The RFI Task Group thanks Mr Turnbull for his years of service as representative. Mr Bodson has been appointed as the representative and HQ staff liaison Mr Hare is the alternate. The C.63 committee is working on developing industry standards of immunity for consumer devices. ARRL serves as a resource to the committee to protect the interests of Amateur Radio. Subcommittee 1 continues to work on a variety of EMC projects, primarily related to test site standardization. Subcommittee 8 deals with various types of medical equipment. It is important that ARRL be involved with this subcommittee because medical equipment can be used in residential environments.
Wireless Modem Jacks: In late 1998, the ARRL received reports about interference near 3.53 MHz from model PX-421 wireless modem jacks. The jacks are an older model made by Phonex, a Utah company. They were installed by the thousands by AT&T Broadband cable (formerly TCI Cablevision). The League and RFI Task Group have been monitoring the status of this problem and have been working with Phonex and AT&T since this problem was first reported. As of December, 2000, the League had over 100 reported cases of interference, with several ARRL Directors indicating that they had also received additional reports. In most cases, hams are now reporting either complete resolution, or a noticeable improvement.
Phonex and AT&T have been continuing to respond appropriately. In mid 2000, AT&T initiated a system-wide recall of the units, supplementing its earlier procedure to respond to specific complaints. At last count, approximately 90% of the installed units have been removed from service, with 85% of the AT&T systems that had installed units reporting that essentially all of them have been removed. The two problem areas appear to be the greater San Francisco/San Jose and the Dallas areas. Some areas are reporting sporadic installations of non-AT&T operated units, either sold retail or installed with digital satellite systems.
Electric Utilities: ARRL has continued to monitor RFI associated with Pacific Gas and Electric. Progress has been slow, but the upper management of PG&E is continuing to work with local offices to resolve reported complaints. In the interim, the FCC sent another advisory letter to another electric utility, Alliant Energy in Iowa. At the time this report was written, Alliant had contacted the involved amateurs, but the problem had not been corrected. ARRL also has about a dozen other active cases involving other utilities, in various stages of resolution. Several of these were recently sent to the FCC for further action. For information about RFI from electrical power lines, see http://www.arrl.org/tis/info/rfi-elect.html.
Home Phone Networking: The Home Phone Networking Alliance is a group that has developed an industry specification for home networking devices that use residential and commercial telephone wiring to network telephones within a building. Dr Strauss is a member of the Home Phone Networking Alliance Technical Committee and is chairman of the ARRL Liaison subcommittee. The testing done jointly by HPNA and ARRL helped HPNA to finalize its Version 2 specification to include a notch in the 40-meter ham band. At the signal level the Version 2 devices use within the ham bands, it is not likely that widespread interference will result, although individual cases are possible.
HomePlug: A similar technique to HPNA is being used by several companies to network computers over residential or commercial electrical wiring. Because electrical wiring is not as well balanced as telephone wiring, there is a greater potential for interference from power-line devices. The League has maintained contact with the HomePlug industry group. The specification is still under development. In December, representatives from several HomePlug companies traveled to ARRL HQ to do some field testing at W1AW and at the station of a local ham, Paul Schaeffer, KB1BE. The results of this testing were mixed, with no perceptible interference noted at W1AW, but with several dB of degradation noted at KB1BE from a test fixture installed in his own residential electrical wiring. Mr Hare will continue to work with HomePlug representatives and will use a Lab-constructed noise generator to do more testing at local amateur installations.
VDSL (Very High Speed Digital Subscriber Line): VDSL is moving closer to reality. VDSL will put very high speed digital signals onto utility telephone wiring. VDSL signals can occupy a significant part of the HF bands. Several industry groups are working on separate specifications and standards. All of these include optional notching for the HF ham bands. Mr Hare will continue to work with his contacts in the VDSL industry to monitor developments and offer them information about Amateur Radio. In October, Mr Hare did some field testing in Phoenix, AZ, using a mobile receiver and whip antenna to determine if an installed "pre-specification" VDSL system (without notches) in Phoenix posed any significant interference potential. With the underground wiring in Phoenix and relatively well-maintained phone wiring, no major interference problems were noted. Additional testing using the noise generator constructed by the Lab will be done at local amateur installations with overhead telephone wiring.
The Future
Interference to hams appears to be the present RFI issue. RFI, especially RFI from unlicensed devices, poses real threats to Amateur Radio. This will continue to require significant Task Group and ARRL staff attention. To the extent possible with existing staff, or with additional resources, the ARRL should increase its contact with standards organization, industry groups and individual companies, and continue to work on all aspects of RFI problems and solutions.
The RFI Task Group is also maintaining close communication the ARRL ad hoc Spectrum Strategy Committee, chaired by ARRL Pacific Division Director Jim Maxwell. Through the work of both committees, Mr Hare has been asked to prepare a plan to identify and address any illegally operated unlicensed devices that operate on the ham bands, primarily through the FCC. In addition, Mr Hare will continue to work with industry and industry groups to address any cases of actual harmful interference from properly FCC Certificated unlicensed devices.
ARRL's information about RFI can be read at http://www.arrl.org/tis/info/rfigen.html.