[Lowfer] WM and MP post dinner shot

[Bill Ashlock]

JD,

Sorry that I said the "equivalent" of 1w. You are right; I should have said "1W of DC input power". I am so used to thinking in terms of typical class D loop transmitters (with no output filters) and ferrite coupling transformers where the efficiency is so high that the inaccuracy of typical measuring equipment could easily outweigh the difference. With my design for the final I don't often measure the RF power and just assume the RF output is very close to 1W when the input DC power is 1W. Haven't yet come up with an efficiency > 100%, so I guess this approach is OK :)

I do have a different interpretation of your: "doesn't that just boil down to "anything's OK as long as we don't get caught?" It doesn't appear to me that the FCC has much to say about the fine points of what we Lowfers have been doing for all these years as long as there are no complaints from interference to other services. Seems to me there is, however, an unofficial code of conduct based on the Pt 15 FCC rules, that has prevailed amoungst Lowfers in the 8 years or so that I have been involved in this great hobby. This code makes for a strong desire for excellence in transmitting effectiveness and the personal rewards for distant signal reports amongst our peers is what this hobby is really all about. They tell me that in the many years that pt 15 operation has been permitted (+40?) there have been only a few that have purposely broken this code of conduct - but to my knowledge they all have eventually been found out and their actions have been brought to the attention of the group as a whole.... and the reaction has been strong. So in effect your "anything is OK"  may be OK as far as the FCC is willing to control but is NOT OK in the minds of the Lowfer community.

I rest my case.

Bill

> From: listread at oswegoblade.com
> To: lowfer at mailman.qth.net
> Date: Sat, 30 Jan 2010 22:14:40 -0600
> Subject: Re: [Lowfer] WM and MP post dinner shot
> 
> Well, Bill, as you know, I've quietly gritted my teeth in the past over the 
> Ken Cornell "interpretation" of the 15 meter antenna rule; that is, anything 
> which would fit in an imaginary cylinder 15 meters long and 15 meters 
> diameter.  The FCC specifically and explicitly rejected that idea, when it 
> was proposed to formalize it in the Part 15 Rules in the 90s.  But I've been 
> willing to quietly disagree with the "15 meters equals 200 feet" notion so 
> long as it was presented as a personal interpretation that falls upon the 
> heads of those insistent on employing it.
> 
> I'm very concerned at the change in wording here:  "The RF impact or 
> interference to others in the local area as well as the skywave interference 
> to others should not exceed the equivalent of an antenna fitting within a 
> 50ft tall and 50ft diam cylinder at 1 watt of RF power."
> 
> First of all, if we're going to talk about the SPIRIT of the FCC Rules, then 
> let's be intellectually honest about that spirit.  Their precise purpose, as 
> stated within the Rules themselves, is to allow operation of low power 
> devices under certain explicitly defined conditions--and even then, ONLY if 
> NO interference is caused to to anyone.  The "spirit" of the Rules is to 
> entirely prevent it from occuring due to Part 15 devices, not to define a 
> safe harbor for how much is acceptable.  So, invoking some personally 
> defined corresponding amount of interference protection to justify a 
> fictional alternative to the actual rule is mighty hard to justify. 
> Ultimately, doesn't that just boil down to "anything's OK as long as we 
> don't get caught?"
> 
> Second, as I said, even the wording of this alternate-alternate imaginary 
> rule itself has now changed from the olden days.  I see it's no longer 
> literally anything which could fit within the imaginary 15mX15m cylinder. 
> That would preclude any side of a loop being 50 feet long, even under Ken 
> Cornell's definion. Now it's "the equivalent of" an antenna meeting that 
> spec?  Who defines that???  And, "at 1 watt of RF power," too.  Forget DC 
> input, I guess.
> 
> Forget making your final or your coupling arrangement more efficient, too, 
> for that matter.  Hence my remark in the earlier post.  If being 
> "equivalent" to this arbitrary new definition is all that's necessary, why 
> stop at 1 watt?  If #12 wire isn't giving the result you want, merely up the 
> power until it gives you the "equivalent" of 1W of RF into an antenna made 
> of 3" copper strap.  Or 6" strap.  Or whatever you personally define to be 
> "equivalent" to those non-canonical conditions.
> 
> With all due respect:  If we can just make up our own rules for convenience, 
> then why bother with experimental licenses or trying to create a ham band at 
> all?  Just go ahead with whatever looks good and try not to get caught, eh.
> 
> Where do you draw the line?
> 
> Joh
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