RE: BIG VTTC project

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

Original poster: "Dave Hartwick by way of Terry Fritz <teslalist-at-qwest-dot-net>" <ddhartwick-at-earthlink-dot-net>

I rewound a large MOT with something like 14 turns of #4 stranded cable.
Using a small variac for greater voltage control, I'm able to drive 4 833
filaments (10V -at- 10 amps each) with no problems at all.

The task of re-winding is a moderate one, accomplished in less than a day. I
removed the MOT secondary with a chisel fairly easily. The hardest part is
threading the heavy cable. I used wedges made of wood to secure windings in
place during the process.
Dave Hartwick

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, January 03, 2003 1:16 AM
To: tesla-at-pupman-dot-com
Subject: Re: BIG VTTC project


Original poster: "Crow Leader by way of Terry Fritz <teslalist-at-qwest-dot-net>"
<tesla-at-lists.symmetric-dot-net>

Sounds like a pretty intense amount of overkill. I'm sure one could convert
a substation transformer into some sort of AA battery recharger too.

Let's say you want 10 volts at 85 amps out of your filament transformer.
That's 850 watts, hardly anythign polemount transformer level, unless you
are taking apart something like a 1kVA "fixed duty" transformer.

One could tear the secondary out of a microwave oven transfomer and make a
filament transformer and skip the hoists and winches, gallons of oil and
extra 100 pounds of unneeded transformer.

KEN

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, January 02, 2003 7:10 PM
Subject: Re: BIG VTTC project


  > Original poster: "Dr.Resonance by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <resonance-at-jvlnet-dot-com>
  >
  >
  > You could easily obtain all four of your 7.5 volt, 21 amp, filiment
  > requirements from a rewound pole xmfr.  Keep the 220 volt primary on and
cut
  > off the HV winding.  They wind on 4 separate filiment windings.  We found
it
  > works out to approx 1 volt per turn, but do a 10 turn test to make sure.
  >
  > You can use this technique to produce a xmfr to provide filiment currents
up
  > to 60 Amperes from any standard pole xmfr core with primary (240 VAC)
  > winding left on and stripping off the HV winding.
  >
  > Dr. Resonance
  >
  >
  >
  >
  > ----- Original Message -----
  > From: "Tesla list" <tesla-at-pupman-dot-com>
  > To: <tesla-at-pupman-dot-com>
  > Sent: Thursday, January 02, 2003 12:00 AM
  > Subject: Re: BIG VTTC project
  >
  >
  >  > Original poster: "Steven Ward by way of Terry Fritz
<teslalist-at-qwest-dot-net>"
  > <srward16-at-hotmail-dot-com>
  >  >
  >  > Hi Greg,
  >  >
  >  > A quick look up on the 4-1000A tube shows a max plate of 6kv at 600ma,
i
  >  > believe.  Hmm, even for just one, how do you suppose you will supply
these
  >  > big tubes?  And how many so you suppose that you would use?  I bet a
pair
  >  > would make one heck of a coil!  Sorry i dont have much tech stuff to
  > offer.
  >  > But i do offer my support!  I would really be interested in seeing a
coil
  >  > of that power being built.  Im working on a dual 833A coil.  But im
still
  >  > learning.  Im sure that someone would know the feasability of using
  >  > 4-1000A's as a VTTC tube.  IT seems like it would work.  7.5v 21A
  >  > filaments, oughhh, thats a big transformer!  And im sure your plate
supply
  >  > will also be a back breaker!  and a circuit breaker :)
  >  >
  >  > Good luck!
  >  >
  >  > Steve Ward.
  >  >
  >  >
  >  >
  >  >
  >  >
  >  >
  >  > >From: "Tesla list" <tesla-at-pupman-dot-com>
  >  > >To: tesla-at-pupman-dot-com
  >  > >Subject: BIG VTTC project
  >  > >Date: Wed, 01 Jan 2003 20:22:43 -0700
  >  > >
  >  > >Original poster: "Gregory Peters by way of Terry Fritz
  >  > ><teslalist-at-qwest-dot-net>" <s371034-at-student.uq.edu.au>
  >  > >
  >  > >Hello all,
  >  > >
  >  > >I can get some near new 4-1000 valves pretty cheaply. These are a 3kW
  >  > >rated transmitting tetrode. How would these go in a VTTC? What
  >  > >configuration should I use (should I wire the screen and grid
  >  > >together and use as a triode)?
  >  > >
  >  > >Cheers,
  >  > >
  >  > >Greg.
  >  >
  >  >
  >  > _
  >  >
  >  >
  >
  >
  >