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2005 News Releases




ARRL Executive Committee Readies Bandwidth Recommendations

Date : 18 / 04 / 2005
Author : Chris Jones - VK2ZDD

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. Meeting April 9 in Denver, the panel adopted recommendations that 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. Nothing will be filed with the FCC until the ARRL Board of Directors 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 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 ARRL Board of Directors initiated work on the bandwidth approach in July 2002, and the League has sought members' comments on specific concepts twice since August of last year. The Board will consider the draft petition, now on the drawing board, at its July meeting.

The proposals the EC has recommended to the ARRL Board abandon the effort 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, leaving any further subdivision up to the amateur band planning process. The EC also acknowledged that band planning mechanisms will have to be improved for this approach to work well.

"Certainly there have to be mechanisms to minimize interference between analog and digital stations, since they cannot compatibly share the same frequency," Sumner explained. "However, using the FCC rules to subdivide the amateur HF bands is the wrong approach. The FCC rules are 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 rather than by FCC rule. 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.)

Sumner has discussed the subject of regulating by bandwidth in two "It Seems to Us . . ." QST editorials: "Regulation by Bandwidth" in the September 2004 issue, and "Narrowing the Bandwidth Issues" in the April 2005 issue.

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 (see accompanying table and charts below for specific frequencies).

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. "Automatic control" segments would be limited to 3.620-3.635, 7.100-7.105, 10.140-10.150, 14.100-14.112, 21.150-21.160 and 28.120-28.189 MHz. The proposal would eliminate the 14.095-14.0995, 18.105-18.110, and 24.925-24.930 MHz automatic control segments. It would move the 15-meter segment up the band to conform to the lower part of the new 3-kHz bandwidth segment.The proposals would make no changes to 60 or 160 meters. Bandwidths of up to 3 kHz--with the special exception for AM and ISB--would be permitted on 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 reminded those who might view the EC's approach as giving too much spectrum over to 3-kHz digital modes that there now is no effective bandwidth limit on HF digital operation. The existing bandwidth limit of 500 Hz applies only to automatically controlled stations in semi-automatic operation. "The band segments that will be limited to 200 Hz and 500 Hz respectively provide greater protection to narrowband operations than exists today," he stressed.

The new proposals take into account the ARRL's prior "Novice refarming" petition to expand some HF 'phone bands, included in the FCC Notice of Proposed Rule Making in WT Docket 04-140.

Sumner points out that amateurs would not have to be able to measure the bandwidth of their signals. "The proposed bandwidths are more than sufficient for 'clean' signals using the traditional HF modes," he said. "Measurement would only arise as a potential problem for those who try to push the edge of the envelope." The Amateur Radio Service has had regulation by bandwidth for certain data operations for many years, Sumner says, without any substantive debate over whether a particular signal was legal or not.

The EC recommendations are likely to generate considerable discussion between now and the July Board meeting. Frequently Asked Questions (FAQs) on the EC recommendations are available on the ARRL Web site.


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