BPL Is 'Spectrum Pollution,' ARRL President Says:

ARRL President Jim Haynie, W5JBP, says Broadband over Power Line (BPL)--if widely deployed--would represent "spectrum pollution" on a level that is "difficult to imagine." Haynie reacted after seeing videotape and early data from recent ARRL field studies in four states where BPL is undergoing testing.

"BPL is the most crucial issue facing Amateur Radio and the one that has the most devastating potential," Haynie said. In terms of interference potential on HF and low-VHF frequencies, "nothing is on the same scale as BPL."

A form of power line carrier (PLC) technology, BPL would use existing low and medium-voltage power lines to deliver broadband services to homes and businesses. Because it uses frequencies between 2 and 80 MHz, BPL could affect HF and low-VHF amateur allocations wherever it's deployed. BPL proponents--primarily electric power utilities--already are testing BPL systems in several markets, and one reportedly is already offering the service. FCC rules already allow BPL, although industry proponents want the FCC to relax radiation limits. It's feared such a change could exacerbate BPL's interference potential.

During the ARRL forum at the West Gulf Division Convention (Austin Summerfest 2003) August 1-2 in Austin, Texas, Haynie previewed a short video highlighting a recent tour of BPL field trial sites by ARRL Lab Manager Ed Hare, W1RFI. In late July, Hare traveled to BPL trial communities in Maryland, Virginia, Pennsylvania and New York to take measurements over significant parts of the HF spectrum and initial readings at low-VHF. Driving a specially equipped vehicle loaded with radio gear and measurement devices, Hare said he didn't need to look long to find BPL interference. "The signals were all over," he said. "The interference found ranged from moderate to extremely strong."

The video shows the S meter of an HF transceiver holding steady in excess of S9 as the speaker emits a crackling din, which one observer described as sounding like a Geiger counter. Only the very strongest amateur signals broke through on 20 and 15 meters. Hare noted, however, that the field strengths of the various systems all were within FCC Part 15 limits for power line carrier (PLC) devices.

Each BPL system exhibited a unique sound depending upon the modulation scheme it used. While in most cases it sounded like static or pulse noise, in one city warbling "birdies" blanketed the bands at closely spaced intervals.

The ARRL already has filed a 120-page package of text and technical exhibits in response to the FCC's Notice of Inquiry in late May. The League plans to file reply comments--responses to comments already filed--by the recently extended August 20 FCC deadline.

Haynie has been doing a bit of traveling of his own, including more than two weeks in Washington so far this year dealing with the FCC and with members of Congress on BPL and other Amateur Radio-related issues.

Countering critics who suggest that the League is only using BPL as a fund-raising ploy, Haynie said the League would not be putting as much effort into attempting to quantify the BPL threat and to put a face on it if it weren't real.

"The BPL industry and their associations have told the FCC and the world that there is no interference potential from BPL systems," Haynie said. "Anyone seeing these BPL signals for megahertz after megahertz for miles along a power line should be convinced that BPL--even operating at the present FCC limits--poses a serious threat to all HF and low-VHF communications."

More information is available on the ARRL Web site http://www.arrl.org/news/features/2003/07/08/1/. Additional information and video clips are on the ARRL "Power Line Communications (PLC) and Amateur Radio" page http://www.arrl.org/tis/info/HTML/plc/.

Source:

The ARRL Letter Vol. 22, No. 31 August 8, 2003

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