On Thu, Mar 18, 2021 at 07:07 AM, WB2UAQ wrote:
Manfred, Have you ever compared the Q readings measured by the old BRC-160 or
the Hp 4342 Q meters against the Q reported by any network analyzer or even
many of the older 4 terminal instruments from the 70's and 80's and maybe into
the 90's?
There is a technique that has been described by Darko Kajfez (EE Professor Emeritus at the University of Mississippi) that actually gives good results for Hi-Q inductors on a VNA. And there is a Matlab application, available for free (if you have Matlab, I think) that implements the Kajfez technique on either an HP 8753 or HP 3577A VNA.
Some time ago, I compared the Matlab application's results with the measured Q from my HP 4342A, and (if my memory is correct) the results were surprisingly close.
If interested, I've put both the Kajfez paper and the user manual for the Matlab website on Github:
(The user manual gets into the nuts and bolts of how to actually make a measurement using this technique).
- Jeff, k6jca
