Re: tuning primary and harmonics

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

Original poster: "S Gaeta by way of Terry Fritz <teslalist-at-qwest-dot-net>" <sgtporky-at-prodigy-dot-net>

Hi guys,

The presence of your secondary causes a "double hump" to appear when you try
to find the resonace of the primary circuit. Remove the secondary and this
effect goes away, and you will be left with only the resonane of the primary
circuit.

Yes, been there, done that, and caught the tee shirt on fire :-).

Cheers,
Sue

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, January 30, 2003 6:38 PM
Subject: Re: tuning primary and harmonics


 > Original poster: "Rob Judd by way of Terry Fritz <teslalist-at-qwest-dot-net>"
<canska-at-a5-dot-com>
 >
 > I would like to know the answer to your question as well!
 >
 > I've observed the same thing on my coil, there seem to be several spots on
 > my primary that result in a large signal on the scope. And each spot is
 > actually a rather large range where there does not seem to be any
 > perceptible difference in the output. These ranges are typically about
half
 > to 3/4 of a turn. From the info I've seen online I always thought the
tuning
 > point would be a very narrow range, not half a turn or more. Anyhow, I've
 > run the coil from each of these ranges and the output is always about the
 > same.
 >
 > I know only one of these spots is actually the true resonant point, and
the
 > rest are harmonics, but I've never figured out how to identify (with the
 > scope, not by calculation) which is the correct spot. In theory, the
signal
 > should be weaker at the harmonics than at the correct tap point?
 >
 > Rob Judd - canska-at-a5-dot-com
 >
 >
 >
 >  > >As I tuned the primary by moving the tap around, I found the amplitude
 >  > >on the scope rising and falling at different tap points.  I guessed
 >  > >these were harmonic frequencies?
 >  > >
 >  > >Anyway, I found a tap point that made the highest single on the cro
and
 >  > >used than.  It was at 9.5 turns.  The coil works fine with this.
 >  > >
 >  > >When I later keyed in the figures into WinTesla, it reported the tap
 >  > >point as being just over 11 turns.
 >  > >
 >  > >I didn't try this far out when tuning the primary, so I am wondering
if
 >  > >I had just found another harmonic at 9.5 turns.
 >  > >
 >  > >Are there a lot of places around the primary that will create a large
 >  > >signal on the scope?  Has anyone else found multiple tap points that
 >  > >make a coil work ok?
 >