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Hams Not Happy With Latest BPL Changes

ARRL still supports mandatory ‘notching’ to protect hams

Amateur radio advocates are disappointed the FCC didn’t do more in its latest action regarding “access broadband over power line” systems.

The commission released a Second Report and Order on BPL Monday. ARRL, a national association for hams, has been active on this issue. It noted that the R&O is in response to a court order that instructed the commission to revise its BPL rules, which ARRL had challenged earlier. The association believes BPL emissions “pollute” the radio spectrum, including bands used by amateur radio, and that BPL has failed as a method of delivering broadband connectivity.

In 2009, according to an ARRL summary, the commission proposed a change to measurement standards used to determine whether a BPL system complies with allowable levels of radiated emissions.

The association had argued that “coupled with a scientifically valid extrapolation factor for determining those levels, mandatory notching of the amateur bands to a level 35 dB below the general emission limit” would reduce harmful interference to hams to a level that could be addressed case-by-case.

But ARRL says the FCC now has decided to adopt neither its own proposal nor mandatory notching. “Instead, the commission has increased the requirement for BPL systems to be able to notch frequency bands to at least 25 dB, an increase of 5 dB from the existing requirement of 20 dB,” it stated. “The commission also made technical adjustments to its rules for determining the distance between a power line and a measurement antenna and for determining site-specific extrapolation factors.”

ARRL Chief Executive Officer David Sumner said in a statement that an increase in notch depth is welcome, but “the value of the change is greatly diminished by the notches not being mandatory. The FCC acknowledges that a compliant BPL system will increase the noise floor below 30 MHz at distances of up to 400 meters from a power line, but characterizes that as ‘a relatively short distance.’ How many amateur stations are located more than a quarter-mile from the nearest power line?” He also questioned other technical aspects of the commission’s order.

ARRL further said that the lack of many interference complaints about BPL systems is attributable not to FCC rules but to a “marketplace failure” of Access BPL, coupled with voluntary steps taken by some system providers.

The group further disputed FCC estimates of how many BPL systems are in operation: “The BPL system database is filled with listings for ‘paper’ systems that were never deployed, systems that have been taken out of service and systems that are at some planning stage or are only offering service to customers within a small pilot area,” Sumner stated. “The FCC’s own report on the status of Internet access services as of Dec. 31, 2010 shows no more than 6,000 customers nationwide receiving service via ‘power line and other’ connections, and about half of those appear to be ‘other.’”

He said ARRL is still looking over the latest R&O but expects to file a petition for reconsideration in support of mandatory notching, particularly since there’s now also interest in BPL as being useful in “smart grid” applications.

FCC Second R&O

ARRL’s statement