----- Original Message -----
From: "Steve Thompson" <g8gsq@qsl.net>
To: <amps@contesting.com>
Sent: Thursday, May 16, 2002 3:49 PM
Subject: Re: [Amps] Nonsense
> On Thursday 16 May 2002 18:02, Maurizio Panicara wrote:
> > Hi steve,
> >
> > there is no doubt that spurs or products of various type may be
generated
> > along a wide spectrum in the most strange or unpredictable ways, but no
sub
> > harmonic is existing in the strict sense, the term is not poor choice is
> > totally unproper.
> > I would like to know, it intrigues me very much, how to produce a real
> > (true) frequency division using analog linear circuits and a sine wave
> > carrier.
> In linear circuits, I expect it's not possible, but few circuits are
without
> non-linear aspects that become significant under some conditions. As best
I
> remember the article I read, the argument goes that if anything (even
noise,
> maybe) causes f/2 to appear in a circuit, then IMD between f/2 and f
produces
> 3f/2, then both f and 2f with 3f/2 produce f/2 and so on, so it can become
> stable and self sustaining if the circumstances are right. The same
analysis
> can apply to f/3 etc. It's very common to find it when doing load pull
tests
> on solid state PAs.
Ahh. That's the best explanation I've heard for what causes sub-harmonics.
Thank you.
Now where's the nonlinearity in the solid state PA's? from the nonlinear
junction capacitance or the nonlinear ferrites?
jeff, wa1hco
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