RE: Barts Flat Coil Dimensions Was: Dimensions of my flat spiral coil

["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 Paul,

> When you measure each strand, are the other two open-circuit?

Yes.

> So there's definately something awry here. Either your measurements are
screwy, or there's some significance to the fact that your measured
inductance for each strand is equal (within experimental limits?) to the
expected total series inductance of the three (which is the same as that of
a single 224 turn winding).

Like I've said before, I have double checked and re-double checked my
inductance readings by measuring solenoid coils I have wound.  The solenoid
coils measure close to the calculated inductance.

>Can you measure the resistance of the windings, see if they are each around
1.8 ohms?

Two of the leads measure 5.1 Ohms and one lead measures 5.2 Ohms.

>While you are at it, check for shorts between the three strands.

They're all shorted at the terminal.  I have no way of removing the terminal
to disconnect the wires from each other.  This is a permanent configuration.
I would have to destroy the coil to do this.

> Now for an interesting test:  Wire your three strands in series, so that
they all add.

That's not possible for the reason stated above.

>It'll be interesting to see the results from some 60Hz inductance
measurements, if you can pull them off.

Help me here.  Where do I find the formula for converting voltage and
current measurements into inductance?  I probably have it in one of my
books, but I haven't found it yet.

Dave