new 833A problems...

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

Original poster: "Steven Ward by way of Terry Fritz <teslalist-at-qwest-dot-net>" <srward16-at-hotmail-dot-com>

Ok,

I have been working on a dual 833A coil project.  IT makes about 24" sparks 
now, but has some problems.  Im using 2 tubes of different make, one is 
westinghouse, the other, unknown.  The problem was that one tube got red 
before the other (the westinghouse got red first).  So i figured i would 
add more grid turns to the unknown tube grid.  This helped at first.  But 
now i have a better filament transformer, and the problem has reoccured.  I 
added even MORE grid turns for the one tube, and this still doesnt make it 
balance out.  The wetinghouse has 16turns, and the other tube has 22 i 
think, thats a 6 turn difference!  One thing i notice is that at various 
fil voltages, the redness will even out between the two tubes. IS it 
possible that the westinghouse is taking excessive current?  and that at 
higher voltages (like 11V where they start to equall out) there is a taper 
in the current draw of the wetinghouse, and the other tube sees what it 
needs to match the westinghouse?  But also realize, it took 11V in to make 
them equal out in redness, and there is still the 6 turn difference in grid 
feedback!  So somethings got to be screwed up here!  The fils of the tubes 
are in parallel, as this was all my transformer would allow.  So is it 
possible to somehow reduce the current to the westinghouse tube?  Both 
tubes look just the same in brightness, so i really just dont understand 
it.  The reason this bothers me is that, one tubes grid is seeing a lot 
more voltage than the other, and i dont know how much becuase i dont know 
how to measure it safely.  But this leads to my next question, could it 
just be the way the tube is made, that it has a less sensitive grid?  And 
does anyone else see the problem with what is happening?  Could this 
possible ruin something?
The coil runs beautifully at full power, there is no stuttering, or 
anything that seems to go along with too many grid turns.  But than again 
22 turns is not considered to be too much, bet 16 seems kinda low for the 
other tube.
Ok, enough rambling, i think i got the point across.  If anyone knows what 
may help, please just say it, even if you arent sure!

Steve Ward.