Re: VTTC help

["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 Steven,

On 26 Sep 2002, at 18:58, Tesla list wrote:

> Original poster: "Steven Ward by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<srward16-at-hotmail-dot-com>
> 
> Well, this isnt my schematic.  And this is where you are a better man than 
> i.  Im very bad at tube circuits, and this is kinda why i started this post. 
>   I cant find any info on all of those small details of B+ or B- or how the 
> tube oscillates, and every other detail that you could imagine!  I guess i 
> could look for some old radio books or something, but does anyone have an 
> online source that could really educate me about what in the world a hartley 
> oscillator is??

A Hartlet ocscillator uses a tank circuit with a tap in the coil to 
derive a feedback signal. A Colpitts oscillator uses a tank 
consisting of a single coil and what is effectively a tapped 
capacitor - two caps in series across the coil with the feedback 
signal derived from the junction of the two caps.

Regards,
Malcolm

 I really need to start from ground zero, and begin to 
> figure this tube technology and these very basic circuits.  But every VTTC 
> site i read seems to be geared towards people that already know what they 
> are doing.  Dont get the wrong picture about me, im excellent with 
> distruptive coils, but i feel thats all that i really know.  I feel fairly 
> competent to deal with the power of a single MOT.  So overall my problem is 
> in the extreme basics of this circuit.  I really dont understand what each 
> part does, and why it does what it does.  Maybe if i knew all of these 
> things, i wouldnt have the problem of needing to copy a design, but rather 
> be able to design my own.
> 
> About the specific question: where is the B+/-?  sorry im even to ignorant 
> to answer this question!  All i can say is that wired according to the 
> link's diagram, it works with some 3" sparks.
> 
> If anyonw can reccomend a good read about tube circuits, id appreciate it.  
> Thanks,
> 
> Steve Ward.
> 
> 
> >From: "Tesla list" <tesla-at-pupman-dot-com>
> >To: tesla-at-pupman-dot-com
> >Subject: Re: VTTC help
> >Date: Thu, 26 Sep 2002 13:54:16 -0600
> >
> >Original poster: "robert heidlebaugh by way of Terry Fritz 
> ><twftesla-at-qwest-dot-net>" <rheidlebaugh-at-desertgate-dot-com>
> >
> >Steve: Not to be to critical, but where is your B+ or B- supply to your 811
> >tube? I see no power applied to the tube, only a grid bias and a floating
> >cathode/fil with a grounded plate. Please review your schematic.
> >    Robert  H
> >
> > > From: "Tesla list" <tesla-at-pupman-dot-com>
> > > Date: Wed, 25 Sep 2002 17:22:00 -0600
> > > To: tesla-at-pupman-dot-com
> > > Subject: VTTC help
> > > Resent-From: tesla-at-pupman-dot-com
> > > Resent-Date: Wed, 25 Sep 2002 17:31:08 -0600
> > >
> > > Original poster: "Steven Ward by way of Terry Fritz 
> ><twftesla-at-qwest-dot-net>"
> > > <srward16-at-hotmail-dot-com>
> > >
> > > Well i just got new caps.  They are Russian 470pf 20kv 60kvar.  I have 2 
> >in
> > > parallel, these are massive caps!! 500 grams each.  They are about 4"
> > > diameter x 1" thick.  Anyway here is the coil i have copied.
> > >
> > > http://www.angelfire-dot-com/electronic/cwillis/811acoil.html
> > >
> > > I had the coil running on some old PP caps, but they got hot and slowly 
> >lost
> > > value.  So i put my new caps on there.  So im having some major problems
> > > with tuning.  I dont really understand how this coil works!!  It doesnt
> > > really say too much.  Why does this coil have 1 inductor(for the 
> >primary)
> > > with a centertap, rather than a primary and feedback winding??  Im 
> >really
> > > interested in tube coils, but i have yet to find a good explenation on 
> >how
> > > they work.  Also, i would love to revise this coil and make a larger 6"
> > > diameter primary, and a taller 3.5" secondary.  If there is anyone out 
> >there
> > > who could perhaps help me to get a good start, or any start on this, i 
> >would
> > > really appreciate that.  If there is the interest in redesigning the 
> >coil, i
> > > can post a list of all of my components or parts on hand.  If anyone has 
> >a
> > > link to some good explenations, i would really appreciate that.  Thanks
> > > guys,
> > >
> > > Steve Ward.
> > >
> 
> 
>