ARRL executive committee readies bandwidth recommendations

Acting on the premise that the amateur bands must flexibly and comfortably accommodate present and future operating modes and technologies over the long haul, the ARRL Executive Committee has reached consensus on
recommendations to the ARRL Board of Directors for a regulation-by-bandwidth proposal.

The recommendations the panel adopted April 9 in Denver will form the basis of a draft ARRL petition to the FCC seeking to govern the usage of amateur spectrum by emission bandwidth rather than by mode.

The proposals remain only EC recommendations at this point, and the League will file nothing with the FCC until the ARRL Board gives its go-ahead. Five of the 15 voting Directors sit on the EC. ARRL CEO David Sumner, K1ZZ, says a key principle underlying the League initiative is that the amateur community must shoulder the responsibility for resolving conflicts among potentially conflicting modes and not expect--or wait for--the FCC to impose its own solutions.

"We are in the early stages of a dramatic shift in amateur HF operating patterns, and it's impossible to predict where this shift may lead," Sumner said. "The FCC rules should not stand in the way of where technology takes us in our fulfillment of the bases and purposes of Amateur Radio."

The bandwidth initiative is aimed in part at encouraging new digital modes, but the primary emphasis is to avoid having to write a new rule every time a new mode bursts onto the scene. The League's proposals will establish a framework that creates an environment for change over the next decade--and perhaps longer, Sumner concluded. The Board will consider the draft petition, now on the drawing board, at its July meeting.

The EC recommendations abandon efforts to have the FCC segregate digital and analog emissions by rule. As the EC sees it, the FCC rules should simply set out band segments in which amateurs may employ bandwidths of up to 3 kHz,
with any further subdivision left up to amateur band planning. The EC acknowledged a need to improve band planning mechanisms for this approach to work well, however.

"Certainly there have to be mechanisms to minimize interference between analog and digital stations, since they cannot compatibly share the same frequency," Sumner explained. But, he says, using FCC rules to subdivide the
HF bands is the wrong approach, in part because they're too static and too difficult to change.

Resolving two issues that have been hanging fire, the EC's proposals would permit semi-automatic control (ie, with a control operator at the querying station) throughout the amateur HF bands. Sumner says that while this carries some risk of interference, the EC believes the amateur community can manage it more effectively through a combination of technology and respectful operating practices. Additionally, automatic control would continue to be permitted at bandwidths of up to 3 kHz in narrow segments of some HF bands.

The EC made no change to its earlier recommendation that the rules continue to permit double-sideband, full-carrier AM and independent sideband (ISB) as specific exceptions to the 3 kHz bandwidth limit--with restrictions of 9 kHz
and 6 kHz respectively--on all bands now allowing 'phone transmissions. (In ISB, or independent sideband, each sideband of a double-sideband signal carries information or data independent of the other.)

FCC rules now permit RTTY and data emissions throughout the HF CW subbands. "It is only through compliance with 'gentlemen's agreements' that RTTY and data signals are not heard in the parts of the band that are generally used
for CW," Sumner notes. The ARRL would propose limiting bandwidth in the "CW subbands" to 200 Hz, which also will accommodate data modes such as PSK31. In addition, the League's proposal would set bandwidth limits of either 500
Hz or 3 kHz in the rest of the bands below 29 MHz. The proposals would not affect 60 or 160 meters.

"The objective is not to expand the phone bands to let robot stations run roughshod over the phone bands, or to effect any other immediate change in amateur operating practices," Sumner emphasized. For example, while the 3-kHz bandwidth segment of the 30-meter band theoretically could accommodate voice, this is prohibited by international band plan agreements because the band is so narrow. Additionally, the Amateur Service is secondary on 30 meters and must protect the primary fixed service from interference.

Sumner pointed out that there now is no effective bandwidth limit on HF digital operation. The existing 500 Hz bandwidth limit applies only to automatically controlled stations in semi-automatic operation. Band segments limited to 200 Hz and 500 Hz respectively provide greater protection for
narrowband operations than exists today, Sumner stressed.

Frequently Asked Questions (FAQs) on the EC recommendations are available on the ARRL Web site.
Direct comments on these proposals via e-mail to bandwidth@arrl.org

Source: ARRL Letter - courtesy of The American Radio Relay League

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