The ARRL has filed a petition to eliminate the automatic transmitter power
control (APC) for Spread Spectrum transmissions over 1 watt in power, with the
possible consequence than many stations will just hang a 100 watt brick on the
output and run 100 watts all the time, whether needed or not.
It is possible that widespread use of spread spectrum will raise the noise
threshold on the entire band, especially if a lot of stations are running more
than 1 watt, thereby hurting traditional weak signal communications.
Spread spectrum was invented during WWII by movie actress Hedy Lamarr as a
communications mode that was hard to detect, and provided SECRET communications
during the war: http://en.wikipedia.org/wiki/Spread_spectrum.
Ever since ARRL adopted Winlink for their own NTS and Emcomm operations, the
possibility exists that the real underlying reason for ARRL's petition might be
to use higher power spread spectrum transmissions to keep ARRL Emcomm and NTS
VHF/UHF communications on the ham bands secure from prying eyes, in the same
way that Winlink uses the F6FBB protocol and Pactor-III for that purpose. In
fact, some Winlink promoters unabashedly promote the use of the F6FBB protocol
in order to keep Winlink email secure from casual monitoring as seen in this
except from a Winlink presentation:
http://mywebpages.comcast.net/hteller/secure.jpg
However, that same security would also make it almost impossible to identify
interfering stations, and hams could no longer police their own bands. Note
that even the use of spread spectrum at one watt or under APC also has the same
security consequences.
Some information on spread spectrum is here: http://www.sss-mag.com/ss.html and
more can be located by Googling for spread spectrum.
Another useful link is here: http://www.x.net.au/white_paper.html
If you are interested in weak-signal VHF communications, and after researching
the impact of spread spectrum to determine if the noise floor really would be
raised by widespread use of spread spectrum by 100 watt stations, you might
want to file a comment as suggested on Eham.net:
FCC Invites Comments on ARRL Spread Spectrum Petition:
The FCC has invited comments on the ARRL's Petition for Rule Making, designated
RM-11325, which seeks to modify a Part 97 rule governing spread spectrum (SS)
operation on Amateur Radio frequencies. The League has asked the Commission to
drop all but the first sentence of §97.311(d), which now requires the use of
automatic power control (APC) for SS stations running more than 1 W, but retain
the 100 W overall power limitation for SS. "The effect of the rule change would
be to eliminate an automatic power control provision that has proven over time
to be impractical" in terms of compliance, the League said in its petition,
filed March 13. Comments are due Wednesday, May 3; reply comments are due
Thursday, May 18. Submit or view comments filed via the FCC's Electronic
Comment Filing System (ECFS) http://www.fcc.gov/cgb/ecfs/. Click on "Submit a
Filing" or "Search for Filed Comments," and type "RM-11325" in the "Proceeding"
field. Be sure to type "RM" in upper case and include the hyphen, but omit the
quotation marks. A copy of the petition is on the ARRL Web site
http://www.arrl.org/announce/regulatory/SS-Rulemaking-Petition.pdf.
I have posted this as a courtesy to you all, and cannot be sure I understand
the impact myself well enough to comment intelligently, so I am not in a
position to debate the issue.
73, Skip KH6TY
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