On Mon, Jul 3, 2023 at 03:27 PM, alan victor wrote:
If difficulty in finding the paper from EDN and the figures, here is a pdf
abbreviated and a test case circuit screen capture. If you are careful in
fixture construction depending on operating frequency, unloaded Q of 350 or
more is easy to obtain. You really need to take care in any Q measurement to
prevent series R losses from accumulating unless you can accurately de-embed
the "stray" R value(s).
Alan
OK I had a go at this with my NanoVNA and got the attached result, which if I follow your calculation correctly equates to Rq = 8.05 ohms.
Coil64 estimates 5.9 ohms which, given the less than ideal test jig I'm using, is not too far off.
Mike
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Mike
