Doc. # 28
For The
American Radio
Relay League
Board of Directors Meeting
July 18-19, 2003
Submitted By
Dennis Bodson, W4PWF
Chairman, ARRL EMC Committee
Mission Statement:
The EMC Committee monitors developments in the Electromagnetic Compatibility (EMC) field and assesses their impact on the Amateur Radio Service. The Committee informs the ARRL Board of Directors about these activities and makes policy recommendations for further action, if appropriate.
The overall goals of the committee are:
Members of the Committee:
HQ Staff:
The role of the ARRL HQ staff consists of the following:
Home Phone Networking:
The Home Phone Networking Alliance (HPNA) is an industry group that has developed a series of industry specifications for home networking devices that use residential and commercial telephone wiring. In years past, the HPNA committee, through the efforts of ARRL HQ staff and Dr. Strauss, did some testing of prototype Version 2 HPNA devices at W1AW. This demonstrated that by not making any use of amateur spectrum, this specification was acceptably compatible with Amateur Radio when used with reasonable telephone wiring.
Recently the HPNA Version 3 specification was ratified. This version adds several new spectral masks to increase data throughput, retaining the protection for amateur radio in the Version 2 specification. Version 2 is now also an internationally recognized ITU standard (G.989.2) and Version 3 is currently going through the ITU process. Note that these spectral notches are also included in the international ITU standards. At the power levels the Version 2 and 3 devices use, it is not likely that widespread interference will result.
Electric Utilities:
Power-line interference has continued to be the number one interference problem reported to ARRL HQ. These cases are being worked on by HQ staff, in cooperation with Riley Hollingsworth of the FCC. Although most of the cases are resolved or well on their way to a successful resolution, a number of older cases are still open. As a follow-up to the letters the FCC sends to electric-utility companies, the FCC has been sending a second letter, reminding utilities of the importance of the FCC rules. The FCC and HQ staff discuss all open cases monthly. Several cases are poised to go to the FCC regional offices for investigation and possible enforcement action.
Power-Line Interference Workshop:
Mike Gruber attended an RFI Services[1] workshop in Maryland. This course offers two days of classroom and field training in the location and resolution of power-line noise. Mr. Gruber uses the information he learned to help electric-utility staff find noise problems.
Broadband Over Power Line (BPL):
Broadband over power line (BPL) is the use of electrical wiring or power-distribution lines to carry high-speed digital signals. There are two types of BPL of concern to amateurs. Both have signals that occupy most or all of the HF range, extending into low VHF. The power-line or electrical wiring can act as an antenna and radiate these signals. In-building BPL can be used to network computers within a building. It uses the building wiring to carry digital signals from one computer to another. Mostin-building BPL operates under the HomePlug industry specification[2]. Access BPL provides broadband Internet access to homes and businesses, using a combination of techniques and wiring. Several field trials on BPL are underway in various cities. ARRL’s information on BPL is found at http://www.arrl.org/bpl. In April, the FCC issued a Notice of Inquiry on the subject of BPL, asking for information on how it should be regulated. ARRL’s filings[3] are being written by ARRL’s D.C. offices, with considerable support from other HQ staff and the EMC-Committee.
Automotive EMC:
Mr. Hare continues as the ARRL representative on the Society of Automotive Engineers EMC and EMR Committees. The Headquarters staff continues to send all reports of automotive EMC problems to interested people in the automotive industry. While these reports are advisory, they are helpful to the industry in planning for future designs. Mr. Hare also serves as the ARRL EMC Committee liaison to the ARRL Industry Advisory Council and he is helping to facilitate communication between amateur and automotive equipment manufacturers.
Cable Television:
As a whole, the cable industry is doing a reasonable job at adhering to the FCC's regulations about leakage and interference. ARRL has received few reports of problems, indicating that most systems are either clean or are addressing complaints effectively. The few cases ARRL has been involved with have been addressed through Mr. Hranac, the cable-industry member of this committee. He generally refers the report to the senior technical management of the involved cable company, who then in turn help the local system resolve the reported problem. The advent of digital cable has not created any major new problems, although the increasing use of the HF "talkback" channels may be responsible for one or two reports that appear to involve HF. The Committee is watching these cases closely, to ensure that no industry-wide problems are at hand.
Mr. Hranac has informed the committee that the widespread deployment of high-speed Internet access using cable modems is part of the reason that leakage is being handled efficiently by the industry. Reliable two-way data service on a cable network requires that the cable company's signal leakage and ingress management be robust.
Database:
The ARRL HQ staff maintain a database of RFI reports and cases. This is used primarily as a case-management tool for the several hundred RFI cases ARRL handles every year, but the information the Lab staff are gathering about typ0es of interference cases, involved equipment and frequencies will provide a wide range of reporting capability. This database was used to help prepare a portion of ARRL’s comments to the FCC BPL NOI.
An example of the report capabilities of the database for 2003 cases:
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Committees: ARRL continues to be represented on professional EMC committees. Messrs. Bodson and Hare continue to represent the interests of Amateur Radio on the IEEE/ANSI C63 RFI committee. Mr Bodson has been appointed as the C63 representative and HQ staff liaison Mr Hare is ARRL’s alternate. Mr. Hare also chairs the C63 committee's ad-hoc working group on power-line communications devices. This continues to be a hot topic of discussion at the C63 meetings.
The C63 committee is working on developing industry standards for immunity, emissions and testing of electronic 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 5 deals with immunity and immunity measurement issues. Subcommittee 8 deals with various types of medical equipment. The ARRL EMC-Committee representation on C63 watches immunity and testing developments.
The Future of EMC and Amateur Radio: Interference to hams appears to be the present major work of the committee. Although immunity problems still do occur, this is being addressed at the national and international standards level and the Committee feels that the changes the HQ staff is planning for the web pages are appropriate. RFI from unlicensed devices poses a major real threat to Amateur Radio at this time. This will continue to require significant Committee 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.
ARRL's information about RFI can be read at http://www.arrl.org/tis/info/rfigen.html.
[1] http://www.rfiservices.com
[2] http://www.homeplug.org/
[3] Insert hyperlink