Re: Modulation

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Shad,
         Thanks for the suggestion. I agree that you could modulate 
the gap firing rate but the idea I had was to make use of an inherent 
property of the system which would allow firing at full power. I 
don't know if anyone else has considered making use of the fact that 
a TC does a modulation job all by itself. Something slightly original 
hopefully.

Regards,
malcolm

On 17 Jul 01, at 18:34, Tesla list wrote:

> Original poster: "Sundog by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<sundog-at-timeship-dot-net>
> 
> Hi Malcom!
> 
> Not a mathmetician (more of a simpleton!), to audio modulate a SGTC, you
> simply need a triggered gap (Marc M. setup).  Put a *tiny* tank cap on you
> coil, 1nf or so, charge it with DC to eliminate resonant problems,  and
> trigger the IGN coil's driver with an audio signal.  I can't foresee
> excellent audio response from it, as you'd be modulating the breakrate.  But
> even half-decent response, triggered with a microphone, would be impressive.
> If anything, it'd let me irritate the neighbors by playing the budweiser
> "Wazzap!" yell via the TC.  They think I'm weird to begin with, so I might
> as well reinforce the image!
> Anywho!
> 
> Shad
> ----- Original Message -----
> From: Tesla list <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Tuesday, July 17, 2001 7:19 PM
> Subject: Modulation
> 
> 
> > Original poster: "Malcolm Watts by way of Terry Fritz
> <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>
> >
> > Hi all,
> >          I've had this crazy idea kicking around for several years
> > and done nothing about it so I thought I'd put it to the list before
> > someone else did. It was sparked (npi) by my thinking about the
> > sideband issue which I replied to the other day.
> >
> >      The nub of the idea is to audio modulate a sparkgap coil. Sounds
> > crazy, right? (NY parlance ;)  Thinking about it resulted in this
> > train of thought: we know that the coupling constant and resonant
> > frequency of the coil sets the sideband frequencies. We also know
> > that k is a pure function of geometry. That suggests that the only
> > way to alter the sideband frequencies (by proxy the modulation
> > frequency) is to alter k, in other words, mechanically alter the
> > proximity/positioning of the secondary relative to the primary. That
> > amounts to moving the secondary with some kind of voicecoil
> > arrangement (possibly using turns on the secondary itself as the
> > motor winding).
> >      BUT, if there was some other way k could be altered that didn't
> > involve moving one of the coils, the goal could be met. If it could
> > be done, one would want air streamers only from the secondary to
> > largely preserve the loaded Q of the system. Sort of a giant ion
> > speaker. Inserting a third coil coupled to the pri-sec with its
> > loading electronically controlled might do the trick although that
> > would alter Ksys which wouldn't be terribly desirable. Question -
> > does such an arrangement alter K or does it just alter M?
> >
> >      Any ideas from the mathematicians on the list?
> >
> > Malcolm
> >
> >
> >
> >
> 
> 
> 
>