Kevin Aylward wrote:
Terry Given wrote:


herewith a self-confessed doesnt-know-it-all's analysis:
IF
y(x) = mx+c (even KA cant argue with the linearity (and
time-invariance) of this....LOL)
THEN
y(ax) = max+c
AND
ay(x) = max+ac

The more I look at this, the more I realise that I am over the heads of
you guys. I am making standard assumptions, and because some individuals
are simple not conversant with common knowledge in the field, make what
are, basically Jesus wept statements.

For starters, there is obviously confusion here on sufficiency and
necessesity. If a function satisfies a(f(x)) = f(ax) is it guaranteed to
be linear? Now, we are discussing practical modulators/amplifiers. Do we
care about dc offsets? For those knowledgeable in the field, do we
usually need to actually specify that dc offsets are being ignored in
normal explanations? for instance, do we usually use a capacitor to
eliminate them?

I must apologise for this. I need to be more aware that many are not
aware of common assumptions, that are taken as read, by those
individuals, who, for example, have been doing analogue design, for
example, for 20+ years.

Kevin Aylward

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