[Antennas] Varactor-Tuned Loop Antennas

[Chris Trask]

>
> The Fair-Rite catalog says that the loss tangent is 3 X 10^-5 at
> 1 MHz and the permeability is 125.  This predicts a Q of 267, assuming
> copper losses are negligible, which they are in this case.  (This
> has been verified by winding an identical transformer with smaller
> gauge wire and seeing negligible change in Q).  Actual
> measurements on the HP4342A Q meter show that the material is
> somewhat better than this, even at several MHz, achieving a Q
> in the 300's to as much as 400.  Do you have a problem with my Q
> measurements?  What do you think the correct value of Q is?
>

    What I have a serious problem with is your claim that the 61 material is
lossless, and your own measurements prove that it isn't.  Plus you quoted
the Fair-Rite spec that shows that it isn't.  If it was lossless as you
claimed earlier, your Q corrected for the bulk losses due to the wire would
approach infinity.

Chris

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