Re: 3rd harmonic trap

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Jimmy Hynes <jphynes@xxxxxxxxx>

Using a series LC as a band pass filter wouldn't work so well either.
Like before, it won't resonate at the harmonics natural frequency, but
it will resonate at a new frequency with the filter. It's like having
two sets of series LCs. they wont resonate at their own frequency, but
there is a frequency that it'll resonate at. Just find the equivalent
since their just in series, you can treat the two Ls and the two Cs as
a single inductor and a single capacitor.

Are you actually having problems with the driver locking onto the
wrong frequency, or is it just to be safe? I think the only way to
keep other frequencies out is to filter in the smarts so that it won't
drive at any other frequency.



On Wed, 23 Mar 2005 08:38:20 -0700, Tesla list <tesla@xxxxxxxxxx> wrote:
> Original poster: "Jolyon Cox" <jolyon@xxxxxxxxxxxxxxxxxxxxxxxx>
>
> if a 3rd harmonic band-reject filter or "trap" would not work, how about a
> band-pass filter tuned to the fundamental of the TC? Would this not a
> correct description of the of  circuit described in the following?
> http://drsstc.com/~terrell/notes/DRSSTCprotec.pdf
>
> Jolyon
> ----- Original Message -----
> From: "Tesla list" <tesla@xxxxxxxxxx>
> To: <tesla@xxxxxxxxxx>
> Sent: Tuesday, March 22, 2005 1:47 AM
> Subject: Re: 3rd harmonic trap
>
> > Original poster: Jimmy Hynes <jphynes@xxxxxxxxx>
> >
> > Sorry, but it won't work. Although it will block that frequency pretty
> > well, the pole is just moved a little bit.
> >
> > It would be desireable to supress the higher modes to keep your driver
> > on the fundamental mode. I tried it once to keep my SSTC from jumping
> > to other modes during ground arcing (base current feedback is more
> > susceptible to it), and realized why it wouldn't work after some more
> > fets blew up :P
> >
> >
> > On Mon, 21 Mar 2005 11:35:56 -0700, Tesla list <tesla@xxxxxxxxxx> wrote:
> >  > Original poster: "Jolyon Cox" <jolyon@xxxxxxxxxxxxxxxxxxxxxxxx>
> >  >
> >  > Dear List
> >  > I am wondering whether it would be possible to use a parallel-resonant
> LC
> >  > circuit in series with the primary of an SSTC as a "trap" to suppress
> the
> >  > unwanted 3rd harmonic mode of oscillation.
> >  > Does anyone know if this is feasible or even desireable?
> >  >
> >  > Jolyon
> >  >
> >  >
> >
> >
> >
>
>