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Re: [Amps] Maximum RF output in practical application: 4-250A

To: "Joe Subich, W4TV" <w4tv@subich.com>,"AMPS" <amps@contesting.com>
Subject: Re: [Amps] Maximum RF output in practical application: 4-250A
From: "Paul Christensen" <w9ac@arrl.net>
Date: Mon, 3 Jul 2006 15:21:30 -0400
List-post: <mailto:amps@contesting.com>
> With voice modulation, it has been proven repeatedly that 3 KHz is
> more than adequate to reasonably reproduce the human voice with
> sufficient intelligibility for communications service.  *YOU* do
> not get to determine the "necessary bandwidth."  That is determined
> by good engineering practice.  If choose to use full carrier DSB AM,
> the bandwidth necessary is no more than 6 KHz (+/- 3 KHz).  +/-5
> or +/-6 KHz is being a spectrum hog.

I was hoping that this discussion wasn't going to morph into one about 
regulatory bandwidth but...

With all due respect Joe, even Hollingsworth concedes the ambiguity of 
97.307(a).  I believe he has generally stopped issuing bandwidth-related 
Advisory Notices to American operators unless the excessive bandwidth is 
related to IMD and /or spurious products (e.g., mis-tuned amplifier), and 
not to those transmissions which are intentionally wider than 3 kHz as a 
matter of increased *frequency response.*  However, the addition of the 
added frequency response may in fact produce those distortions which in turn 
creates a reasonable basis for issuing a formal notice (I was thinking ahead 
of W8JI's response on this one <g>).

Pursuant to my last written correspondence with Hollingsworth on the matter, 
as long as the intentional AM & SSB frequency response of transmissions 
occur well outside uncrowded band conditions and adjacent interference to 
pre-existing communications does not occur, then these transmissions are 
perfectly allowable under the current rules.  Unfortunately, there seemingly 
is always one or two bad apples that ruin things for others.

Section 97.307(a) is one of many flexible rules in which hard barriers do 
not exist for several reasons: (i) most amateurs do not have the skills, nor 
the resources to accurately measure bandwidth; (ii) to codify bandwidth 
requires a reasonable means of measurement to defend one's self against 
bogus complaints to the FCC; and (iii) the spirit of the amateur service 
rests in, among other things, with the fostering of experimentation.  To 
place hard limits on bandwidth necessarily restricts some future use of 
technological innovation and arguably, may discourage experimentation.

One can make a legal, rational argument (as I think the other Joe is 
attempting) that by strict definition, the minimum bandwidth necessary for 
communications can vary widely.  Lawyers make a living out of parsing the 
meaning of governmental rules, statutes, and contractual terms and 
conditions -- Like this one:

Part 97.307(a):

"No amateur station transmission shall occupy more bandwidth than
  necessary for the information rate and emission type being
  transmitted, in accordance with good amateur practice."

The issue is this:  If my intent is to transmit with an "information rate" 
of ITU 6K00J3E, then by strict definition of Section 97.307(a), I should not 
be transmitting with a bandwidth that exceeds 6kHz, in accordance with "good 
engineering practice" for that *particular* information rate.  The rule does 
not expressly forbid the use of bandwidths in excess of 2, 3, or even 6 kHz. 
The rules could have long ago expressly forbid the use of such bandwidth. 
If the FCC wanted to place hard limits on SSB or AM transmissions they could 
have included it in the CFR.  The League's relatively recent, misguided 
attempt to regulate by bandwidth would have been the first of any such 
strict limits to the American HF AM and SBB amateur modes of service.

In cases of ambiguity, federal due process demands that the less restrictive 
interpretation is applied to the rule.  These arguments go on every day 
concerning new state and federal legislation.  In fact most municipalities 
have their own city attorney's office whose job it is to function as an 
interpreter to statutory construction.  Here in Jacksonville, that consists 
of a team of attorneys on the city's payroll.

The reality is this:  If I hear W4TV transmitting with what appears to be 
more bandwidth than is allowed by some future rule, all that is necessary 
for the FCC to issue a formal Advisory Notice is the receipt of my one (1) 
complaint.  The FCC need not investigate the source, nor the veracity of the 
complaint - and typically doesn't.  The FCC is under an obligation to 
respond and act.  W4TV is then left with the defense to prove that he was 
compliant.  And exactly what evidence is W4TV going to produce that he was 
compliant on the date and time of the alleged infraction?  Answer:  None.

Paul, W9AC 

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