Re: BIG VTTC project

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

Original poster: "sundog by way of Terry Fritz <teslalist-at-qwest-dot-net>" <sundog-at-timeship-dot-net>

Hi Greg,

   So far as I know, you can tie the grid and screen together and use them 
as a triode.  You may want to look into using a dropping resistor on the 
grid to lower the voltage on it.

  For a filament transformer, take an old MOT and use a hacksaw to cut off 
the secondary (Cut right next to the core, then drive out the other half 
with a hammer and small socket), as per my buddy James.  Easiest way to do 
it.  Wind it with a dozen turns of magnet wire, and put 120v on the 
primary, then remove or add turns till you're at the filament 
voltage.  Filaments are fickle, and want to be within pretty close 
tolerances.  (usually a tenth of a volt or so).   Once you find the right 
number of turns, remove the magnet wire and re-wind the MOT with heavy 
gauge wire.  I use two strands of 12ga stranded copper THHN for my dual 833 
coil without problem, and 0ga (only 5 turns) for my RS1026's filament 
tranny.  When working with the tube coil, it's best to leave the filaments 
on until you're done or going to leave it set for awhile (more than 10 min 
in my case).  Less less wear and tear on them.

    Should rock pretty good!  Keep us posted, and hope it helps!

Shad

   Make sure you're using a beefy tank cap, because those two tubes can 
move a decent amount of power.  For a plate transformer, you can use two 
MOT's in series (no doublers).  Ground the case of the first MOT, then run 
the HV lead to the case of the second MOT.  You'll have to phase them 
properly, but that's easily done.

At 10:22 PM 1/1/2003, you wrote:
>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.
>

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Shad (Sundog)
G-5 #1373
"Ever stop to think, and forget to start again?"
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