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Old May 12th 10, 09:35 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Computer model experiment

On May 12, 3:16*pm, K7ITM wrote:
On May 12, 12:58*pm, K7ITM wrote:
...

To see what I mean, try entering D=10mm, N=10, len.=20mm,
d=1mm, and check what C(L,p) is reported. *Now try changing D in 1mm
increments up and down. *OK, so I don't trust the reported C(L,p)
value, ...


OK, it also helps to RTFM. *The text down below the inductance
calculator explains about this some. *Also, I should have said that
you need to set the "design frequency" to something low (e.g. 10MHz)
to see the effect. *However, the text suggests that C(L,p) value would
be larger than expected...and I've also seen it for some coils to be
considerably smaller. *So I end up, then, not finding the lumped model
including C(L,p) being very useful for the things I do, where I want a
model that gives me _decent_ agreement over a broader frequency range,
rather than perhaps more exact agreement over a very limited frequency
range (as happens when the reported value of C(L,p) gets very large;
try "design frequency" = 1MHz for that coil).

Cheers,
Tom


Remember, I have always specified that one does not go beyond the
units supplied by Maxwell, Maxwell did not use lumped loads. It is
stipulated
that equilibrium is paramount as soon as you see the "=" sign. Thus I
can say I am persueing exactnes or accuracy and not fudging.It was
when Maxwell followed the edict of the "equal" sign that he was forced
to add the particle elevation vector by the addition of displacement
current even tho
he could not describe the addition. To him it was a mathematical
equation and nothing else and without explanation of the process.
Art