Here is an article from the weekly ARRL Letter of April 25, 2003. Vol. 22, No 17

I received this from Kent via e-mail 6-20-03

==>"BROADBAND OVER POWER LINE" POSES HF INTERFERENCE THREAT <==

The FCC soon will invite public comment on the concept of using existing electrical power lines to deliver Internet and broadband service to homes
and offices. The Commission initiated a Notice of Inquiry (NOI) in ET Docket 03-104 when it met April 23. What the FCC calls "Broadband over Power Line" (BPL) is a form of carrier-current technology typically known as power line communication (PLC). Whatever its name, the technology is raising serious interference concerns within the Amateur Radio community, since BPL would apply high-frequency RF to parts of the power grid. One aspect of the NOI is to gather information on potential interference
effects on authorized spectrum users.

"Entire communities will be affected, so every amateur in that community could have part of the radiating system 'next door' on the power wiring on
his or her street," cautioned ARRL Lab Supervisor Ed Hare, W1RFI. Hare chairs the PLC Work Group of the IEEE C63 Accredited Standards Committee
on Electromagnetic Compatibility <http://c63.ieee.org/>.

The complete NOI has not yet been released, and until that happens, the FCC will not formally accept comments in the proceeding. The ARRL will be
among those expected to submit detailed comments in ET 03-104.

So-called "access BPL" would use medium-voltage (1 kV to 40 kV) power lines to deliver Internet and broadband applications. Hare says access BPL is likely to be a more significant interference source than in-building PLC technology "because overhead electrical wiring is a much better antenna than the electrical wiring within a building."

ARRL CEO David Sumner, K1ZZ, editorialized on the subject of PLC in "It Seems to Us . . ." in the October issue of 2002 QST. "Is it possible to do
power line communications without causing interference to over-the-air communications?" Sumner asked. "Count us among the skeptics. What may be a fine transmission line at 60 Hz looks more like an antenna at HF." Hare said his own computer analyses of interference potential from access BPL/PLC suggest "a significant increase in noise levels" from deployed systems.

The FCC appears enthusiastic about BPL, however, saying it has the potential to "provide consumers with the freedom to access broadband services from any room in the house without adding or paying for additional connections." The Commission also touted BPL as "a competitive alternative to digital subscriber line and cable modem services."

New digital power line designs use multiple carriers spread over a wide frequency range--from 2 MHz up to 80 MHz--and capable of high data rates--up to 20 MB/s, the FCC said.

In addition to viewpoints on interference potential, the FCC also has requested comments on the current state of high-speed BPL technology, test results from BPL experimental sites, appropriate measurement procedure for testing emission characteristics for all types of carrier-current systems, changes that may be needed in Part 15 technical rules, and the equipment approval process to foster the development of BPL.

Tests of BPL are under way in several states, including Alabama, Maryland, Missouri, New York, Ohio, Pennsylvania and Virginia. Hare says ARRL Lab
personnel will visit some of the test cities this spring to take field measurements to quantify the potential for interference to Amateur Radio operations.

BPL/PLC technology already has been deployed in some European countries, and amateurs there have complained about interference. Japan--responding in part to concerns expressed by its amateur community--decided last year
not to adopt the technology because of its interference potential.