How to optimize parameters for making a coil with high-Q?

I want to make a simple coil (inductor) with a Q value as high as possible.
Now, I would like to know if there are simple guidelines on how to choose
the parameters to obtain this. Parameters are:

- thickness of the wire
- number of rounds
- length of the coil
- area of cross-section

I understand that a realistic description of a coil involves (at least) a
parallel parasitic capacitance C and a series resistance R.
The resulting Q value would then be Q = (1/R) sqrt (L/C). Is this indeed the
relevant expression for Q?
If the coil is operated at a frequency of the order 1 MHz, can we assume for
R just the 'DC' series resistance of the wire, or does it change with
frequency?
And, how can C be calculated?
For inductance L I have found some useful information, but for the others
not yet...


Any suggestions? Thanks for your time,

Arthur C.



.

Relevant Pages

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