RE: Longitudinal Waves

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

Original poster: "David Thomson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dave-at-volantis-dot-org>

Hi Ed,

I searched the NIST web site for all kinds of terms related to flat spiral
coil formulas and didn't find anything.  Do you have a link I can use?

Dave

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Thursday, February 14, 2002 7:28 PM
To: tesla-at-pupman-dot-com
Subject: Re: Longitudinal Waves


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

> I have measured the inductances on this smaller coil.  This is explained
in
> my online notes.  The actual measured inductances don't even come close to
> the calculated inductances even on single wound flat spirals.  The
measured
> inductances are generally three times the inductance of the calculated
> inductance using the formula for spiral coils.

	Something seems wrong there.  There are plenty of formulae available
(Bureau of Standars Circular No. 74 for starters) which can give almost
any desired accuracy.  Were your measurements at frequencies low enough
that the distributed capacitance had negligible effect?

Ed