The ARRL has again urged the FCC to go forward with a proposed new Amateur Radio allocation at 472-479 kHz (630 meters) and to establish service rules for Amateur Radio operation at 135.7-137.8 kHz (2200 meters). The League reiterated its August 31 arguments in favor of flexible FCC Part 97 regulations it its September 30 reply comments to the FCC’s April Report and Order, Order, and Notice of Proposed Rulemaking (R&O/NPRM) in ET Docket 15-99. That R&O/NPRM raised several questions regarding how Amateur Radio might coexist with PLC systems used to control the power grid. Targeting comments filed by the Utilities Telecom Council (UTC), the ARRL called on the Commission to ignore UTC’s call not to allocate 630 meters to Amateur Radio. It asked the FCC to implement a notification procedure for amateur stations within 1 kilometer (0.62 miles) of a transmission line carrying PLC and where the PLC system is operating on frequencies within or which overlap the 2200 or 630 meter bands.

“The comments of UTC, without the benefit of any technical component or argument, oppose the allocation of the 630 meter band to the Amateur Service, and suggest overly and unnecessarily conservative regulation of Amateur operation in the 2200 meter band,” the ARRL told the FCC. “Whatever protection criteria are ultimately deemed to be necessary with respect to the 2200 meter band, those criteria would be applicable and sufficient as well with respect to the 630-meter band,” the ARRL said. “There is no technical justification offered by UTC for withholding the 630 meter allocation.”

The ARRL also urged the FCC to reject what it called “UTC’s inchoate proposal” to elevate the unlicensed status of PLCs operating between 9 and 490 kHz, purportedly to protect them from interference “caused by amateur operations,” while not making any accommodations to address PLC interference to Amateur Radio operations. “UTC cannot have it both ways: It cannot enjoy the benefits of unlicensed operation under Part 15 of the Commission’s rules as a carrier-current, unintentional emitter and at the same time claim the protection afforded an allocated, licensed radio service,” the ARRL argued.

While the UTC has offered to work with the FCC, the ARRL characterized the UTC’s comments as “distinctly unhelpful” in terms of providing information regarding the prevalence and location of PLCs that need protection, the interference potential from Amateur Radio operation and notification requirements, and just how much protection the PLCs actually need. “They are not responsive at all to the plethora of questions asked by the Commission in the Notice,” the ARRL continued, “and those points that UTC makes are unsubstantiated.”

The ARRL said that PLCs are not nearly as prevalent in the 630 band as the UTC has suggested, and that, in any case, such systems already operate as unlicensed Part 15 services that must not cause interference to licensed services and must accept interference from them. The League has indicated that any rules applicable to 2200 meters should also suffice for 630 meters. Nonetheless, the League said, it’s willing to work with utilities in setting up a notification procedure to address the unlikely possibility that Amateur Radio operations in the two bands might interfere with critical PLC systems.

“In order to implement this, UTC should be called upon to provide to ARRL or to the general public a list of transmission lines carrying PLC which make use of either of the two subject bands, thus to facilitate notification,” the ARRL reply comments said. “This would have the double benefit of encouraging a complete PLC database while permitting accurate determinations of which transmission lines are carrying PLC which have any potential at all of adverse interaction with amateur stations.” Once notification is made, though, the burden should shift to the utility to establish that there would be harmful interference, the ARRL said.

“The likelihood of an amateur station conducting operations in the 2200 or 630 meter bands from a fixed station located less than 1 kilometer from a PLC-carrying transmission line upstream from a distribution substation is exceptionally low,” the ARRL asserted. “Many transmission power lines do not carry PLC at all. Most PLC systems do not use the very small amateur allocations at 2200 or 630 meters.”

The League concluded by calling on the FCC to allocate 630 meters to Amateur Radio, as proposed in the Notice, reject UTC’s proposal to elevate the status of PLCs, and implement a notification procedure for amateur stations within 1 kilometer of a transmission line carrying PLC in or near the two bands, and to make the LF and MF allocation changes in Part 2 and the Part 97 service rule changes, “as proposed by ARRL and not otherwise.”