Kapanadze Cousin - DALLY FREE ENERGY

[Dog-One]

So what does the PO telecom cable Blue White do, may i ask ?

If you look at the original Akula circuit, he was pulling his high voltage from the yoke with a separate winding, rectifying it and using this to drive his Tesla coil.  Ruslan doesn't do this and I know why--it's very difficult to do without detriment to the main pair of driver MOSFETs.  If you can manage to get things right as Akula did, it saves on components, but I find it smarter to build modules each having a specific function they way Ruslan's design shows.

[TinselKoala]

I'm now wondering... "how hot is hot?" 

Because a couple of years ago, IIRC, I tested an IRFPG50 mosfet to destruction with a thermocouple attached, and it still worked fine at over 200 degrees C. Electronic solder melts at 190 C or so!
So I'm thinking that running a TO-247 package mosfet at 100 degrees C or even higher is probably still OK. It might be scary, it might be a fire hazard, it might burn your fingers, but it probably will still work fine in an oscillator. 

[Dog-One]

I'm now wondering... "how hot is hot?" 

That is an interesting thought.  Here's a slight variation...

I have some TO-247 Ohmite high power resistors.  Suppose you thermally attached this resistor to the MOSFET, ran the MOSFET normally with minimal load and cranked-up the juice to the resistor.  In this arrangement you could tell real easily how the heat changes the performance of the MOSFET.  Maybe place a thermocouple in between the two for accurate measurements.

On the other hand, I have a tendency to think if the device runs hot, maybe I'm doing something wrong or using the wrong part for the particular application.

[NickZ]

"On the other hand, I have a tendency to think if the device runs hot, maybe I'm doing something wrong or using the wrong part for the particular application".

  Me too.   Or something... So, what's up with that mosfet heat thing. I'm still banging my head against the wall.
I'll look into it again tonight.  Seam like this happens to me every time I take any anything apart, and can't get it working right  again.
Last time I took my Kacher circuit apart it took me three days to get it running again.  I guess that I should get used to it....

[Hoppy]

Nick,

At a guess, you may have too many primary turns on the yoke.