Here's the second part of my "quest for the truth"!
While trying to validate performance test results with computer models, I
find more conflicts with the effect of inductor Q on overall performance.
Without going into details, I decided I needed to actually measure the Q on
a number of different inductors. At one time I had access to a HP
instrument that read out Q directly. Since then, I have tried a few
different methods of approximating the Q, but I never got any results I
thought was close enough. I did try a cap to tune the coil and calculated
the unloaded Q of the tank from the measured bandwidth. This method assumes
a very high Q cap will cause the tank Q to be approximately the coil Q.
Since the Q numbers always came out a lot lower than I expected, that was
probably not a valid assumption.
Does anyone have a better method of measuring inductor Q easily?
Has anyone tried to correlate modeled effects of Q verses measured effects
of Q on a practical short (very short) antenna?
73,
Larry - W7IUV
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