Re: SSTC, Modes and soft switching

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

Original poster: "Steven Ward" <srward16-at-hotmail-dot-com> 




> >
> > I believe it has been suggested that from observation of the
> > performance that a system with an offset works better. Has anyone
> > quantified the offset and or got a frequency response of such a
> > system?
> >
> > Comments anyone?
> >
> > Bob
>
>A very loose observation from practice on my part suggests that best
>performance is obtained when the primary of a standard sparkgap coil
>is tuned to what would have been the lower sideband in a system with
>equal pri-sec tuning with the same coupling constant. A frequency
>sweep shows the LSB enhanced at the expense of the upper.
>
>Malcolm
>

Im not sure i understand all of the theory yet, but all of my SSTCs (dual 
resonant type) all tune to the lower frequency of the split.  This seems to 
produce the best spark lengths.  I prefer using feedback from the secondary 
to control the whole system and compared with using a VCO or feedback from 
the primary, the secondary feedback produces the best output.  Also note 
that i must tune the primary considerably lower than the operating 
frequency.  If i remember correctly, in my largest SSTC system the primary 
is tuned to around 40khz while the secondary's fundamental frequency is 
about 50khz.  The whole thing actually operates at 46khz.

Steve