So long story short - i made some recent changes to my vttc coil concerning the primary circuit and grid coil. The changes i made were:
Changed the tank capacitance from 5nf to 2.5nf and thus increased the number of primary turns (and the diameter by about 1/8"). I also rewound the grid to match the new primary diameter.
Ive made plenty of changes like this and have been able to get things working one way or another so i dont think its the "stats" of the coil causing a problem. The only variable i can see is the physical winding direction of the grid is NOW the same as the secondary. In all other setups it has been wound opposite. Is this a problem??
I havnt tried rewinding the grid yet, but i have tried everything else and still no sparks, not even a "feedback" hum from the variac.
Things ive already tried:
I had an analog ammeter in series on the grid coil after the capacitor before ground and wasnt reading anything anymore. Ive switched all the leads going to the primary and grid. Checked along the secondary with a neon light. Physically flipped both grid and primary coils. Tried various tap points and slight changes in coupling values for the coils. Ive checked the frequencies with an O-scope and assuming i did that right everything is as close as it ever was. Ive taken voltage measurments all over the circuit and things seem right.
Thanks for thoughts.
Simon
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla