Because it stores energy.
73
Gary K4FMX
> -----Original Message-----
> From: Amps [mailto:amps-bounces@contesting.com] On Behalf Of Fuqua, Bill
> L
> Sent: Monday, January 12, 2015 10:59 PM
> To: Roger (K8RI); amps@contesting.com
> Subject: Re: [Amps] The genius of ham radio
>
> As to a question I asked earlier.
> Why is a tuned circuit sometimes called a tank circuit?
> This is a term that goes back more than 100 years.
> Any guesses?
> 73
> Bill wa4lav
> ________________________________________
> From: Amps [amps-bounces@contesting.com] on behalf of Roger (K8RI)
> [k8ri@rogerhalstead.com]
> Sent: Monday, January 12, 2015 11:40 PM
> To: amps@contesting.com
> Subject: Re: [Amps] The genius of ham radio
>
> Aren't proven theories then referred to as physical laws?
>
> 73
>
> Roger (K8RI)
>
>
> On 1/12/2015 12:58 PM, Jim Brown wrote:
> > On Mon,1/12/2015 8:36 AM, greg greene wrote:
> >> the difference between
> >> theory and practice - is the difference between theory and practice'
> >> what
> >> he meant by that was that theory is the guide - practice is result,
> when
> >> the two don't match - review both. Theory is never 100% - that is
> >> why it
> >> is theory
> >
> > The word "theory" here is misapplied. Somehow, we in the radio world,
> > long before most of us became hams, divided the FCC exam into a
> > written exam, which was CALLED "theory" and the CW exam. What that
> > exam covered (and still does) is a combination radio Rules, operation,
> > and fundamental physical principles. NOT unproven "theory."
> >
> > Human understanding of how things work has been well known for a LONG
> > time. Nearly 100 years ago, Bell Labs published the concept of the use
> > of feedback to reduce distortion in amplifiers with a corresponding
> > reduction in gain. The fundamentals of transmission lines and
> > antennas are also that old. Before that work was proven by disciplined
> > experiment, it could reasonably be called "theory," even though it was
> > clearly proven by the math.
> >
> >> - the more we observe the results of practice - the closer we get
> >> to redefining the theory, and then the closer we get to refining the
> >> practice.
> >
> > Jim Garland addressed this quite well in his post. REAL components are
> > not ideal -- inductors have series resistance and parallel
> > capacitance. When we look at a circuit diagram that shows an inductor
> > and ignore that fact, WE have failed to apply fundamental principles.
> > This is not a failure of "theory" nor those principles. Likewise, when
> > we look at a resistor and fail to see it's self inductance (and even
> > parallel capacitance), and look at a capacitor failing to see it's
> > series and parallel resistances and series inductance, it is WE who
> > have failed, NOT "theory" -- those fundamental principles. And, of
> > course, active components -- tubes, transistors, and diodes also have
> > strays.
> >
> > I was trained as an EE, and spent much of my life in the field of
> > "engineering." Real engineers are trained to understand the whole
> > picture, the strays, the costs of eliminating or reducing them, and
> > when to stop with "good enough." We don't need, nor can we afford
> > "ideal" -- we must work with the real estate that our home sits on,
> > with the sky hooks that are on it, and cash in our bank account to
> > build antennas that "work."
> >
> > Inside our radios and amplifiers, we must look for and understand what
> > Henry Ott calls "the invisible schematic hiding behind the 'ground'
> > symbol," as well as the complete schematic that includes those stray
> > Rs, Ls, and Cs. Failure to do that is OUR failure, not "theory," those
> > fundamental principles.
> >
> > Understanding HOW antennas work allows us to achieve a better result
> > faster. Sure, we could build a dipole, operate it at various heights
> > in increments of 5 ft, and use a drone with instruments attached take
> > a lot of measured data to see it's directional pattern, both vertical
> > and horizontal. Bring a very fat wallet to this process. OR, build a
> > model of that antenna in NEC and have it compute the 3D pattern at
> > various heights in increments of 5 ft. I've done that in a day or so.
> > I now KNOW, in dB, the value of 10 ft of additional height on 80, 40,
> > and 20M. That work, BTW, is on my website.
> >
> > http://k9yc.com/VertOrHorizontal-Slides.pdf
> >
> > 73, Jim K9YC
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
>
>
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