Tank coils and inductors are very different from antenna losses - In the
former, you typically have larger current - A Q of 10 implies that there is 10
times as much power circulating in the LC as there is flowing “through”. And
there’s not much other loss, so the inductor loss dominates.
In an antenna, you have the radiation resistance (72 ohms for a resonant
dipole) plus the loss resistance (a few ohms), so the total power being lost
is smaller - 10% if it were 7 ohms, which is huge. And it’s spread out over
many feet, so you don’t see it warming.
Where antenna resistance can really bite you is when you have a “physically
small” antenna (magnetic loop, anyone?) and the radiation resistance is small
(because of small physical size) so the loss resistance is big compared to
Rrad, so you can get big percentage losses.
On Sat, 30 Sep 2023 14:00:25 -0400, Ken WA8JXM <wa8jxm@gmail.com> wrote:
I expect results would be frequency dependent since the skin effect is
frequency related AFAIK.
I have some war surplus rotary inductors made with solid silver wire.
You can add that to your list also :-)
Ken WA8JXM
On Sat, Sep 30, 2023 at 1:45 PM Mark, K5AM wrote:
> > Jim wrote:
> > I have wound identical coils using silver plated copper,
> > copper, and also 304 SS. The aluminum coils ran hot.
> > The SS coils ran stupid hot.
>
> Interesting!
> It would also be great to see data comparing:
> silver plated copper
> copper
> oxidized copper
>
> 73,
>
> Mark, K5AM
>
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