Re: Stop the nonsense

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

> I may well miss the point here, but I know how to measure Fo of a flat coil
> and I can explain it to someone else. I can even measure Fo for a slinky.  :)
> I don't know hot to make
> a flat secondary coil.  :(

	The latter is easy as, for example, in the case of the spider-weave
coil which is wound around a slotted form, with the windings passed
between the slots to support them.  Coils such as this were used in the
"early days of radio", both because they had a neat appearance and
because they were supposed to have low distributed capacitance.  I'm not
sure about the latter, but have such a coil which I wound many years
ago.  It's about 6" inside diameter, 18" outside diameter, and has an
inductance of several millihenries.  Q in the 50 kHz region is fairly
poor.  I know where it is and will try to dig it out and measure it.

	Spirals of flat conductors were used among other things because they
were reasonably compact and it was easy to vary the coupling between two
of them by sliding them apart or hinging them and moving them as pages
are opened in a book.  Suspect that appearance was a factor too, as they
are much harder to make than the solenoidal coils which were used at the
same time.

	As for any "magical properties" I can only speculate.  As a confirmed
skeptic I have a strong opinion, but as has been pointed out, "a closed
mind".

> Happy day,
> Ralph Zekelman

Ed