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Modeling a magnifier
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From: Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent: Sunday, March 15, 1998 3:46 PM
To: Tesla List
Subject: Re: Modeling a magnifier
HI Bert, all,
> From: Bert Hickman [SMTP:bert.hickman-at-aquila-dot-com]
> Sent: Thursday, March 12, 1998 8:35 AM
> To: Tesla List
> Subject: Re: Modeling a magnifier
>
<snip>
> > I ran a well tuned magnifier and examined the waveforms coming off
> > the secondary in considerable detail. The familiar old beat envelope
> > associated with the primary/resonator trade is in full swing.
> > Quenching the gap with no secondary breakout looks to be as far away
> > as ever. Calculating k off the beat envelope and ring frequency
> > suggests that Antonio's contention is correct: k for this system
> > came in at 0.086 compared with k for the driver system alone at >0.4
> > There was clear evidence of the resonator frequency dominating system
> > frequency. Primary is tuned to 485kHz. Resonator is at 463.7kHz. Ring
> > captured on scope is about 465kHz (same as resonator within margin
> > of error). There is no magical voltage rise when the gap finally
> > does go out. It looked for all the world like a two coil system.
> > One of the more interesting waveforms occured when Ep was upped to
> > allow corona to break out. You could see the resonator ring up with
> > the usual sinusoidal envelope and then abruptly drop amplitude
> > somewhat and ring down in linear fashion. Attached sparks caused it
> > to drop far more abruptly. Attached corona sometimes caused and
> > exponential decay.
> > This investigation is acknowledged to be far from complete. For
> > one thing, primary Q was pretty bad. That will be corrected by oil
> > filling the driver system (due mainly to corona). A low Xp didn't
> > help either (14 Ohms).
> > The main conclusion I drew from this is that mags are a great way
> > to get the same bang for buck from a much smaller resonator because
> > clearances between resonator on driving system are no longer an issue.
> >
> > Malcolm
>
> Malcolm,
>
> Thanks for a very revealing experiment! A couple of questions:
> 1. If the effective k is this low, are the frequency splitting effects
> correspondingly reduced?
Only to the extent that the bandwidth of the system is reduced to
what k and Q allows. Component Q was still plenty high enough that
energy trades went to completion and the DSB envelope was in full
swing.
> 2. Perhaps even more importantly, do you see the difficulty of quenching
> being commensurable to a two-coil system with this low value of
> effective k? Previous results with others on the list who've made high
> power magnifiers seem to suggest significant problems with quenching
> more commensurate with the driver's higher k.
I do. I saw no more gap distress than I have with two coils set to
the same k. I am sure this will run OK with a static gap.
Regards,
Malcolm
> Your conclusion certainly seems to make sense. Very interesting work!
>
> -- Bert --
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