RE: Primary and Secondary winding direction

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

Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>


Tim -

Tesla was interested in the 1/4 wavelength secondary and used it to find the
optimum toroid (secondary terminal) of a Tesla coil.You can find more info
by going to my web site and checking on "6. Optimum Toroid". Click on  -

    http://home.att-dot-net/~couturejh

John Couture

------------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Thursday, January 04, 2001 6:33 AM
To: tesla-at-pupman-dot-com
Subject: Re: Primary and Secondary winding direction


Original poster: "Tim by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<warpath-at-wtp-dot-net>

Hi All, I, too, have heard of the "1/4 wavelength secoundary winding".
Could someone explain what this is and
where it came from? The first person I talked to about making a coil talked
of this. Thanks, Tim

Tesla list wrote:

> Original poster: "Peter Lawrence by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <Peter.Lawrence-at-Eng.Sun-dot-com>
>
> Alan,
>      I have secondaries that are wound in both directions (my hand-wound
ones
> go one way and my lathe-wound ones go the other) and I have not observed
any
> difference.
>
> I also took a conical primary that was too highly coupled because the cone
> was too high an angle and turned it over and made it nearly flat, which
> successfully reduced the coupling and therefore reduced the racing sparks
> I was having, and other than the coupling effect, the reversed direction
of
> the primary did not have any other effects. Output sparks were the same.
>
> ICBWB, I'm pretty sure that the primary and secondary coils are 90-degrees
> out of phase during oscilation (not 180 as someone has suggested), the top
> of the secondary will be at max volts as the primary has zero volts (max
> current) across it, so it does not really matter what polarity the
secondary
> top is (winding direction will determine polarity at the top, relative to
> polarity (inside verses outside of the spiral) of the primary) - because
> 180 degrees later the sec top polarity will be reversed but the primary
> will be back at zero volts (max current) again.
>
> At least to me symmetry arguments are always convincing, IMHO the
requirement
> for winding direction is a myth.
>
> -Pete Lawrence.
>
> (ps, I think there are way to many myths in tesla coiling, I myself fell
for
> the "1/4 wave length secondary wire" myth, and ever since have been
doubting
> as much as possible everything I read, and try to verify things with my
own
> experiments as much as possible).
>
> > Hello All,
> >
> > Are there any rules governing the direction in which the primary coil
and
> > the secondary coil are wound?
> >
> > I have read on the web that the primary and the secondary *must* be
wound in
> > the same direction. I think that this is due to: the current induced in
the
> > secondary coil
> > makes a magnetic field that is the opposite of the primary magnetic
field
> > and so the magnetic fields mutually annihilate each other.
> > I am not completely sure about this, I haven't sat down and done the
math
> > :-(
> >
> > My assistant suggested that you just swap the leads to the primary coil,
> > (the primary tap lead and the center connection lead.) However, the
> > resonation is like AC so therefore it will not make much difference, the
> > induced current in the secondary will still make an opposing field to
the
> > primary, as *both* magnetic fields have swapped polarity. Am I right?
> >
> > Thanks heaps,
> >
> > Alan Williams