fun with loading
Just an afterthought.
Q is dimensionless quantity. Therefore it cannot be measured directly.
It is always obtained as the CALCULATED ratio of TWO independent
measurements or previous calculations.
Its only use is to predict, by further calculation, other properties
of a circuit such as bandwith or voltage magnification. It is just a
convenient intermediary which can frequently be bypassed or done
without.
It can seldom be determined accurately which is a measure of its true
worth. Your guess is as good as mine at high frequencies.
The common or garden Q meter indicates only the resistance of a coil
relative to a standard of some sort. The coil's inductive reactance
is already known, or is related to the capacitor and frequency, or can
otherwise be calculated. Here you still have a pair of independent
measurable quantities.
I'd better stop here. The subject has been over-complicated quite
enough. Here in the Black Country, the weather is beautifully fresh.
Spring is well on its way.
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Reg.
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