There hasn't been much discussion lately about the FCC Notice of
Proposed Rulemaking (NPRM) on RM-11708/WT Docket No. 16-239
https://apps.fcc.gov/edocs_public/attachmatch/FCC-16-96A1.pdf This will
greatly affect RTTY, data, and CW, and I believe it deserves attention.
Everyone agrees that advancement of the radio art is an important goal.
But the MF/HF RTTY/data subbands lack the width for wideband
experimentation.
If the symbol rate and bandwidth limitations are removed from the
RTTY/data rules as proposed, the likely outcome would be appearance of
many wideband signals on the relatively narrow MF/HF amateur bands. As
an example, the ARRL originally advocated a bandwidth cap of 2.8 KHz.
In the ACDS subband between 7100 and 7105 KHz, only one such
transmission could occur at a time without exceeding the band limits.
In the NPRM, the FCC suggests that the limitations imposed by 97.309(a)
would limit transmission bandwidth. My interpretation of this rule is
that it requires use of the Baudot, ASCII, or AMTOR bit patterns. I am
not clear on how this limits bandwidth. Further, I believe that
97.309(a)(4) opens the door on virtually any transmission scheme. It
states that operators ". . . may use any technique whose technical
characteristics have been documented publicly . . . " It does not
specify method of publication. Presumably, any transmission scheme
published online somewhere would qualify under this provision, with
whatever bandwidth it might require.
In the rules on ACDS in 97.221(c)(2), the FCC has already cited
RTTY/data bandwidth of 500 Hz as a sort of de-facto standard. If the
proposed new rule were to adopt 500 Hz as the bandwidth limit, this
would be a reasonable compromise between current practice and the desire
to eliminate the archaic symbol rate rule for MF/HF. Perhaps agreement
could form around this.
I don't claim to be an expert and invite criticism of the points I make
here. But I think it is essential to identify any flaws in the FCC's
current proposal and point them out in appropriate comments. From the
way it is worded, it is clear that the FCC is not certain that the
proposed rule will offer the hoped-for benefits. They ask for comments
that address the questions they raise, such as the trade-off between
increased bandwidth and user access. Although some comments have been
submitted, I believe we should provide the greatest possible number of
the strongest possible arguments. FCC RM-11708 comment site:
https://www.fcc.gov/ecfs/search/filings?proceedings_name=RM-11708&sort=date_disseminated,DESC
I hope you will respond on this reflector to the issues I raised.
Bill/KC2EMH
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