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ARRL General Bulletin ARLB020 (2019)

ARLB020 ARRL Renews Request for FCC to Replace Symbol Rate with
Bandwidth Limit

QST de W1AW  
ARRL Bulletin 20  ARLB020
From ARRL Headquarters  
Newington CT  September 19, 2019
To all radio amateurs 

ARLB020 ARRL Renews Request for FCC to Replace Symbol Rate with
Bandwidth Limit

In ex parte comments filed on September 17 in WT Docket 16-239, ARRL
renewed its request that the FCC delete symbol-rate limits for data
transmissions in the Amateur Service rules. As it did in its initial
filing, ARRL asked the FCC to couple the removal of the symbol rate
limits with the adoption of a 2.8 kHz bandwidth limit. In response
to a 2013 ARRL Petition for Rulemaking (RM-11708), the FCC proposed
deleting the symbol-rate limits but declined to replace them with
the 2.8 kHz bandwidth that ARRL wanted.

The 2013 ARRL Petition for Rulemaking (RM-11708) can be found online
in PDF format at, .

"This proceeding addresses an update to the Commission's rules that
is needed because a limitation in the rules unintentionally is
inhibiting US amateurs from employing the latest improvements to
some of the digital modes," ARRL said in its remarks. "Data signals
commonly used for daily communications as well as in disaster
situations have bandwidths in the range of 2.5 kHz and must co-exist
with other modes that use bandwidths as narrow as 50 Hz."

ARRL said the 1980s-era symbol-rate limits now inhibit the use of
some efficient data modes. "The symbol rate limit uniquely prevents
radio Amateurs in the United States from experimenting and
innovating with a class of modern digital communication techniques
that already are widely used in other countries," ARRL told the FCC.
"The limit also impairs the ability of Amateurs to improve support
that they offer in times of disaster."

Repealing the symbol-rate limit would "allow shortened transmission
times for the same amount of data without increasing the bandwidth
occupied by the signal," ARRL contended. "Other Amateurs would
benefit by the resulting reduction in potential interference."

ARRL's remarks also addressed issues raised by other parties.
"Discussion by commenters in this proceeding delve into subjects
well beyond its scope," ARRL said, noting that it had attempted to
broker consensus among "some of the most active commenters" with an
eye toward exploring possible areas of agreement for the FCC's
consideration. ARRL noted that the parties to the ARRL-arranged
talks declined to forward to the FCC "joint recommendations on which
conditional agreement had been reached."

"The issues discussed with the parties are outside the scope of this
Docket and would require a further Notice of Proposed Rulemaking
before final consideration," ARRL observed. "Some of the same issues
also are raised in petitions for rulemaking on which the Commission
has sought comment. Given the policy as well as factual
disagreements evidenced in the record, we understand that the
Commission may decide to consider some of these issues."

One of those issues involves automatically controlled digital
stations (ACDS). Commenters' concerns focused on interference that
could occur with a move away from symbol-rate criteria. ACDS with
signals wider than 500 Hz and below 29.7 MHz are confined to
specific subbands. ARRL recommended that the FCC consider rule
changes that would have all ACDS stations and digital stations with
bandwidths greater than 500 Hz share identified subbands.

ARRL said if additional signals are added to the ACDS subbands, as
recommended, that it would strongly support expanding the HF ACDS
subbands. But, ARRL added, "changing the subband boundaries requires
study and careful consideration of trade-offs, because any changes
will affect multiple user interests." ARRL referred subband
reformulation issues to its HF Band Planning Committee for study and

Some commenters also raised the issue of obscure and encrypted
messages. ARRL pointed out in its ex parte remarks that it remains
opposed to encryption in the amateur bands, but disagreed "with
commenters who argue that the digital modes being used by radio
amateurs around the world are per se 'obscured' or 'encrypted.'"

ARRL noted that FCC rules permit the use of "new and innovative
digital modes" without prior approval, if specified conditions are
met. Digital techniques must use approved codes with publicly
documented technical characteristics, and their purpose must be to
facilitate communication and not to obscure content.

"Some commenters allege that specific messages violate the
Commission's rules governing encryption, third-party messages,
pecuniary interests, objectionable language, or commercial
carriage," ARRL noted, and they have called for open-source decoding
software to aid in enforcing the applicable rules. "We observe that
recently there have been laudable efforts at self-policing," ARRL
said. "Unresolved complaints are appropriately handled as
enforcement matters rather than as rulemaking matters."

ARRL concluded, "It is vital that the rules governing the Amateur
Radio Service facilitate continuation of its experimental traditions
and purposes. Using the Amateur spectrum 'sandbox' for innovation
and development of new ideas and technologies is of significant
public benefit."