Re: NEC-LIST: Coil Q

Here us a link on proximity effect. It appears that the close winding
spacing that I often use only increases the resistance by a factor of
two.

Reference Data For Radio Engineers (ITT, 1979, page 6-4 has a plot for
finding solenoid inductor Q. An example:

F = 5 MHz
Length/diameter ratio = 1
Winding center-to-center distance = 2X wire diameter
Coil diameter = 3 inches
Q = 670

K6STI calculator: Q = 710

Hand calculation accounting for proximity effect and capacitance. Q =
990

I will build the coil and measure it on a VNA. I will have to series
resonate it to bring it into the range of the instrument.

    Dave Cuthbert

http://www.csee.umbc.edu/~plusquel/650/slides/transmission_lines3.html

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