In a strongly worded letter to the FCC, the League has once again asked the Commission to shut down the Manassas, Virginia, BPL system because it's still causing harmful interference to Amateur Radio and otherwise does not comply with FCC Part 15 rules. The December 19 letter from ARRL General Counsel Chris Imlay, W3KD, was in response to a November 30 letter from Spectrum Enforcement Division Chief Joseph Casey, who suggested further cooperation between the complaining radio amateurs and the city-owned BPL system. Imlay said more meetings and discussions about ongoing interference are no longer productive while "this hopelessly flawed BPL system" is allowed to continue operating.

"These meetings have not produced any solution to the interference problem but have, instead, created the illusion that the problem is being addressed," Imlay wrote. Ham radio complaints of interference from the BPL system date back to early 2004. "This system should have been taken off the air long ago, pending reconfiguration or re-engineering of it," he added, "and the only operating that it should be doing is for purposes of interference testing."

Communication Technologies (COMTek) operates the BPL system over the municipally owned electric power grid using Main.net equipment on frequencies between 4 MHz and 30 MHz. The League said the FCC has not discharged its "most fundamental obligation" to prevent or resolve interference issues involving the Manassas system, which, the League charged, only remains operating "because the Commission, for political reasons, has consistently refused to enforce its rules with respect to BPL."

The League told Casey that the only solution at this point is to order the Manassas BPL system--an unlicensed RF emitter permitted to operate only on a non-interference basis--to cease operation except to test for interference.

The Part 15 BPL rules the FCC adopted in October 2004 require a BPL operator informed of harmful interference to "investigate the reported interference and resolve confirmed harmful interference . . . within a reasonable period," Imlay pointed out. "No reasoned examination of this case could produce a finding that this rule has been complied with in Manassas," he added.

Imlay says that at a December 13 meeting, COMTek and the City of Manassas "openly acknowledged the interference to amateur stations" but claimed that until a month or so earlier, they had been unable to "notch" amateur allocations because they didn't yet have the equipment to do so. "By the admission of COMTek, the capability of reducing interference in this system does not exist," Imlay noted.

Previous meetings between the complaining radio amateurs and the BPL operator "produced no measurable results," Imlay contended, referring to the response of Donald Blasdell, W4HJL, to Casey on December 9. At one point in the system, interference was reported at S9 plus 40 dB on typical ham gear. "That level precludes virtually all Amateur Radio communications," he asserted.

Imlay took the opportunity to again point out that the Manassas BPL system is out of compliance with 15.615(a) because its operator failed to provide full information to the public BPL database by the November 19 deadline.

"ARRL again requests that the BPL facility at Manassas, Virginia, be instructed to shut down immediately," the League's letter concluded, "and that it not resume operation unless the entire facility is shown to be in full compliance with Commission rules regarding radiated emissions; with the non-interference requirement of Section 15.5 of the Commission's rules; and not in any case until thirty days subsequent to full compliance with Section 15.615(a) of the rules."

Field tests conducted by Manassas radio amateurs established that the city's BPL system "was an interference generator at distances of hundreds of feet from the modems on overhead power lines," the ARRL told the FCC October 13. "It was also, incidentally, determined that the system was susceptible to interference from nearby radio transmitters operating between 4 and 20 MHz," the League added.

Source:

The ARRL Letter Vol. 24, No. 50 December 23, 2005