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Parallel and Series LCR Circuit Qs



Hi all,
I have a question regarding basic ac theory, something I thought I had
sorted, but this does not appear to be the case. I was looking at
building a simple crystal set and so had a look at what the ideal design
involves. Apparently you should use more capacity and less inductance,
that is, a coil wound from fairly stout wire and a large tuning
capacitor.
Now, am I right in thinking that the Q of a parallel tuned circuit is
relevant to current magnification, that is, you want as much current to
flow through the coil and capacitor so as to have a large Q. If this is
so, then this explains this design for crystal sets.
However, I am no left wondering about tesla coil secondaries. I was
under the opinion that a secondary resonator needed to have a fairly
high Q; I also thought that the secondary resonator was a series tuned
circuit. If this is the case, then there should be more inductance than
capacitance to get a high Q-factor. However, from what I have read (an
understand) the design dictates a large top capacity and relatively
small inductance; this resulting in white streamers showing a relatively
substantial current.
I once built a TC that had a large secondary inductance and small
capacity, as per a high Q series resonant LC circuit. This TC produced
nice violet streamers, indicating very little current but high voltage;
was this poor design?

I guess what I'm asking is what makes a high Q in a parallel and series
tuned LCR circuit. Also what physical parameters does this dictate, i.e.
number of turns and thickness of wire in the inductance.

Another question is regarding primary and secondary TC circuits. As far
as I understand it, the primary is a parallel tuned circuit, while the
secondary resonator is a series tuned circuit.

These are pretty basic questions (I think?) but I am not sure of their
answers.

Thanks in advance,

Gavin