[1000mp] Fw: Hi-Fi SSB and the application of the law - Cross Post

[WD8ARZ]

----- Original Message -----
From: "Paul Christensen"
Sent: Thursday, March 07, 2002 17:25
Subject: Hi-Fi SSB and the application of the law


Recently, while I was researching topics on digital voice modes, I
discovered several articles authored by the legendary Doug Smith, KF6DX.
Doug has published several thought-provoking articles at the academia-level
which intelligently addresses the future use and application of digital
voice modes in the H.F. spectrum.

In the January issue of QST, page 31 to be exact, Doug further addresses the
current legal issues surrounding the use of digital voice techniques at
frequencies below 30 MHz.  An excerpt from the QST article entitled "Digital
Voice: The Next New Mode?":

"Is Digital Voice Legal on the Amateur Bands? If So, What Frequencies and
Emissions May Be Used?

Part 97 of the FCC rules states that phone signals-whether analog or
digital -must remain in the phone subbands. 15 That's mainly a concern for
the eight HF bands where phone is used. In the VHF bands above 10 meters,
phone is legal for US-licensed amateurs at all allocated frequencies, with
the exception of 50-50.1, 144-144.1 and 219-220 MHz. The rules also say that
no transmission "... shall occupy more bandwidth than necessary for the
information rate and emission type being transmitted, in accordance with
good amateur practice." FN16  That's purposefully vague: The Amateur Radio
Service is free to experiment with almost any mode you can think of, as long
as it's not wasteful of bandwidth .... While the symbol rate (baud rate) of
digital data transmissions is limited on many US ham bands, the baud rate of
digital phone transmissions is unlimited! FN17"

End of quote.  FN (Footnotes appear at the end of this message)

While I do not believe Doug is a attorney, his interpretation of 47 CFR
97.307(a) mirrors that of recent discussions I've had with Commission
attorneys.  Isn't the law great?  Here is an excellent example of a codified
rule in the form of a federal statute and yet, the rule fluid; there is no
hard-and-fast, nor black-and-white interpretation as to how or why we must
draw a demarcation to the use of occupied bandwidth.  What?  You mean
amateur's really are free to experiment with almost any mode so long as it
is not wasteful of bandwidth?  Argument: If the overarching experimental
goal is the aspiration of fidelity, and that in order to achieve that
fidelity, additional bandwidth is necessary to meet the fidelity
criteria...guess what?  It conforms to 47 CFR 97.307(a).  Yes,
interestingly, the same interpretation of the law as it applies to digital
voice techniques ALSO APPLIES TO THE PURSUIT OF HIGH FIDELITY SINGLE
SIDEBAND TRANSMISSIONS.

During the past several weeks, I have been listening to discussions and have
personally been involved in discussions which have presented questions over
the use of extended-bandwidth SSB transmissions. Sadly, these discussions
end in manner where walls are being built around and between people.  In one
instance, a person was singled-out and needlessly provoked on the air in
front of a global audience which occurred as the result of interference from
moving off frequency.  Was the interference real?   Absolutely. But the
interference and ensuing controversy could have been easily circumvented
through communication and understanding.  How ironic in a hobby where we
embrace communication?  As an Amateur how do you deal with similar issues?
Through confrontation or by working out our issues as caring adults?

In two other recent instances, a Florida OO has allegedly been issuing
warnings with the comment "excessive bandwidth."  As I understand it, three
actions from an OO, is an invitation to have the issue routed up the chain
of command directly to the Commission.   Is this really necessary?  Provided
that we are sensitive to the interference issue, we can all get along.  For
example, if there's relatively little adjacent activity on any given band,
it is perfectly acceptable to open up the transmit bandwidth provided that
the requisite under 47 CFR 97.307(a) is achieved and that interference is
not caused to any existing adjacent communications.  In any event,
please...let's communicate with one another before allowing an issue to
needlessly escalate out of control.

73,

-Paul
FN16 - 47 CFR 97.307(a).

FN17 - P. Rinaldo, W4RI, "Is Digital Voice Permissible
under Part 97?" sidebar to C. Brain,
G4GUO, and A. Talbot, G4JNT, "Practical HF
Digital Voice," QEX/Communications Quarterly,
May/Jun 2000. The article may be
found on ARRLWeb, www.arrl.org/tis/info/
digivoice.html. "The Help Desk," elsewhere
in this issue, contains an updated list of HF
band plans.