Tube coil funkiness

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

Hi All!
 
            Well, I'm on vacation, so that means I get nearly a full week of
nothing but TC'ing!  Muhahahah!!!!   
 
Last night I sat down and tried to figure a better way to get my tube coil
tuned.  I'm no genius, but I am armed with a signal gen and an o'scope ;)  
 
  I put the secondary in place in the setup and basefed it with the signal
gen.  I fed the signal gen's signal to ch2 and my antenna to ch1.  Tinkering
with my scope found a menu packed with stuff for it to measure for me (RMS
voltage, pk-pk, period, freq, etc.)     Anywho!   
  My secondary's Fres dropped considerably in the setup, but no matter, I made
a note of the frequency (359khz). 10khz either way it dropped off a *lot*.  
 
  I then removed the secondary from the setup, moved the antenna to ~1' away
from the primary, and powered up the system to ~1A input.  Just enough to get a
solid oscillation from it.  After fooling with the trigger level, I got a
*very* solid waveform on the scope.  Then it was just a matter of shut it off,
move the primary tap, do it over, till I got the frequency to 350khz.  I then
moved the scope outta danger, put the secondary back in place, and fired 'er
off.   All in all, it was pretty anti-climactic.  I still have a big problem
with the grid leak network (new cap and resistor time, I'm tired of messing
with it).  But at least I got a couple of inch sparks out of it instead of 
just some fuzz.  It's behaving like my filament transformer isn't properly
grounded.  Strange, that's for sure.  But I have 3 more 833's to try in it,
plus I now have a way to accurately tune a push-pull setup (testing 1/2 the
primary at once).  One thing to look out for!!  In my previous tests, I removed
the tank cap and let the other half of the primary float.  It looks like it
autotransformered to some nuts voltage (or maybe some fluke resonant thing) and
blew a thick 2" spark against the primary form.  Not pretty, but fixable.  
 
What exactly determines grid current for the coil?  The ratio of turns of grid
to primary?  size of the grid cap?  It's really high for the 833, and I don't
like it bein' that high. Bad for the tube. 
                                                                           
                      Shad