Nice flame like arcs from my VTTC

Plasma flame VTTC grounded arcs

Stable VTTC Single MOT and GU 81m

Finally got power and tuning to enable long runs. Tube glows very dull red after a few minutes run and stabilises with forced cooling. The single mot with doubler doesn't heat up appreciably. Doubler diode is nice and cool as well.

40 turns primary .5mm
12pf 25kv Vacuum Capacitor tank
300 turns secondary .5mm
30 turns .25mm feedback
1kohm grid with 0.01uf mica 6kv
5kv diode 200ma with 3300pf 4kv bypass
0.95 2200vac mot cap in doubler
100pf 25kv ceramic mot bypass cap
Frequency unstable 800khz to 1mhz

Blown up countless diodes and other components. 

One more thing you need a tank capacitor or the primary will resonate with the transformer and the intercapacitance of the tube and pop diodes or short out the transformer.

Going to leave as is with no more mods.

EDIT: After a blown MOT I added a rf filter to the ground of the MOT and used a rf ground for the secondary. I also added 3.3nf 12kv across the MOT. I also addes a safety gap across to MOT for overvoltage protection.  I hope this will be enough rf and overvoltage protection.

VTTC sparks

Thyratron Crowbar Tesla Coil

Thyratron Crowbar Tesla Coil (TCTC)

Thyratron Crowbar Oscillator 

Please note there may be incorrect polarities used in the schematic. But my description will hopefully explain how I want it to be wired.

1.) Power on, Tank cap is charged
2.) Pulse fires main thyratron (THY1) which discharges capacitor through the
primary
3.) The capacitor now discharged fully recharges and the thyratron (THY1) short
circuits the main power supply.
4.) Hopefully at this point we have a sharp enough pulse to power T2 and
ring up the secondary
3.) T2 now has a pulse which is stepped down to 200v which triggers the
second thyratron (THY2)
4.) The second thyratron (THY2) now short circuits the power supply hopefully
extinguishing the first thyratron (THY1)
5.) C3 is now fully charged and the current through the second thyratron (THY2)
is regulated by R1
6.) C3 acting as a DC block once charged, now R1 engages and reduces
current shutting off the second thyratron (THY2)
6.) The second thyratron (THY2) extinguishes and the cycle repeats, C3
discharges through R1

Note: L1 oscillates through D2 which protects THY1