Kevin Aylward wrote:
gwhite wrote:
Kevin Aylward wrote:

In summary, there are differing concepts of what linearity is being
understood to mean in the real world. A point was made that a class A
transistor amp modulator achieves modulation via completely linear
means. This is clearly not correct as was showed in my last post, and in
engineering practise, its probably impossible to generate a modulation
function, in a direct electrical circuit, without explicitly using an
inherent nonlinearity of a device. One only has to look at any practical
modulator. That is, modulation and non-linearity, is isomorphic in a
practical sense. However, there is certainly a valid argument, that in a
strict mathematical technical sense, a "linear" system can encompass a
much wider class of systems all under the banner of "linear". This is
pretty much obvious, for example, even a Bessel integral transform is a
"linear" transform, but would actually severely distort a signal
considerable. However, this extended view of "linear" has little do with
real analogue circuits, where linear is generally accepted to mean
linear gain with offset, and is a technicality that has little, or even
no value at all. The point has been made, but there is yet to be any
real physical example presented, where such a technical point has any
practical merit in real circuits.

Kevin Aylward

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