EDIT: And I just got another PM from Enjoykin, also, just now.  He says that he was not banned by Stefan. And wished me a nice day.
  I gave him your info Verpies. He'll be in touch. Ha!
  I should of given him Meta's info instead, they'll have a great time together.  Horse science, rose gardens, and all.

Yes Enjoykin certainly helped us a lot,  a good man

BTG Reference mannual by Enjoykin2017 !!

Nice time of day. Maybe we will find a common language. 

Directly I will tell you that at forums strongly I don't sit. There is no time!! However now for the 5th time I will build up another Akula device  for increasing output power. Are there  new ideas about how to ??.... And in matter of fact, people here look for a everything but not at things needed. All these devices  works at a basis of standing and traveling «waves». Correctly speaking not «waves» but fields, because only the fields can bring a force – do any action. It is necessary to catch up the clue, at first the movement of particles in the coil. I.e. as Kapanadze also did by means of a electronic- tester or the ampermeter. Only in case of HF frequencies no ampermeter will help you and it will be necessary to catch an effect with oscillograph.

1st rule:
Wind the coil of 40 meters. 

2nd.:
Find its resonance frequency (1/4 lambda) than the Inductor should be  ¼ x 40m = 10 meters of the same wire diameter (for example 2,5mm square).

You should connect the signal generator output to 10 meters inductor coil, and then excite with sharp rectangle pulses at a frequency from 1 MHz and well  above (fine manual sweep of sig.generator will do a job) ,  doing so far until on 40 meters output Grenade coil  doesn’t  appear nice sine curve.  Pure sine with Maximum Possible Amplitude is what you  are looking for. It is very desirable to buy normal quality Laboratory sig.generator !! It should have fine voltage regulation at output from 0 to 20 volts. You will try to obtain maximum possible sine amplitude (Grenade output) and you should fine adjust frequency at the tenth parts  of kilohertzes until  nice sine way with max amplitude doesn’t start  dance on oscillograph screen. That  dancing point is moment of appearing yours Grenade Standing Wave (correct Standing Field) resonance !!!!

You should download and watch all Ruslan videos from Dimus W channel  https://www.youtube.com/channel/UCH-1HcD0wjwCpJpNs3ZG8mg  – to see how it look like at oscillograph.

«Амплитудная модуляция 1» → https://www.youtube.com/watch?v=JHipZaGwd48
Амплитудная модуляция 2» → https://www.youtube.com/watch?v=SA-0KHY8qR8&t=18s

You should fix correct frequency and output voltage as critical values. Under this conditions it is necessary to make and tune your  working device generator instead sin.generator..

Further...

You should wind Tesla secondary coil (or Katcher secondary) under this frequency and voltage set, where correct effect was gained. Then you will doing everything as Akula or Ruslan did. In this case all wish to replicate Akula device. Go forward!!  You need to fix every part in your build-up to be beautifull and well rigid, without forgetting that the resonance and effect can get away in cases you are «fixings on snivels» or incorrect placing Watch Akula and Ruslan videos to see how to place your buid up parts.  You need to  gain an effect and correct working operation, but not a full ready made non-working device.  As soon as you begin to understand what further is needed  to do, you will be able to move well quickly. And so.... The Tesla (Katcher)  as you know, can zap a sine curve easy,  if it was overdriven. You need a Silent Tesla work.!!

Let's allow your Tesla frequency is turned out to be 1,820MHZ. Fucc… frequency, but alas. It is necessary to set up Tesla exactly on it freq. Akula has applied ferrite bar between Tesla secondaty and a toroid (Tesla Antenna) over the bifilar inductor. It is just exact setup with very fine tuned circuit alignment (parts of Hertz). It is necessary before device first start. Then the device holds and keep  it and isn't so important if where appear some slides - little frequency shifts but not in big ammounts. Device will cope with.!!

But!!  Besides that... Whats  than ?

On the Inductor (bifilar coil) you should give sharp rectangle pulses signal with frequency of 1/50th of Tesla. You calculate:= 1820KHZ : 50(harmonic) = 36,4 KHZ,  rectangles pumping frequency through a decoupling (Big Yoke core) from 23-29 wire turns,  about  2,5mm square. I will repeat, it is necessary to setup working voltage on this 50th harmonica not at 10-20 volts, but much above. Approximately minimum 50-60 volts and better the higer and most important to catch the same Standing Wave Dancing Effect on sine at Grenade outputl. Further!! Don't forget that the Tesla doesn't need the strong power and high amperage for proper work. It isn't necessary to let Tesla sparking and zapping around break through. Or there is nothing from effect!! It is the best to make electronics well controlled Tesla (Katcher).

So on continue: On Grenade output should appear voltage difference aboutf 195-200 volts.

This voltage won't be higher. Why? Later we will return to it.!! It is necessary to wind your Grenade coil (reactor),  to receive exactly the necessary voltage you wish.  It requires lot of experiments and lot of conductors to make 240V output Grenade.  You should remember that you push conducting current in the Grenade by means of transverse field created  byTesla (Katcher). Also keep in mind that in the Grenade coil another field was formed  as a result of rectangles pumped current at 50th harmonica . Those field particles (heavy electrons) permanently rotate to the left and to the right. Giving them acceleration rhythm from the pulsating Tesla, you in fact accelerate all those heavy particles in the conductor crystal lattice. It is haemorrhoids behaviour hard understanding, but it is simple a Fact.

The Tesla (Katcher) shall work only in ½ half-cycle or to say simple only from one branch of push-pull transistors. It is highly desirable to Control wok of Tesla coil with continues  trains of pulses produced by master oscillator with fine tuning of duty cycle and pulse width. When all of you, make accurately device setup, you will see positive action in form of  the gaining high current effect in case you are changing pulse train width, duty cycle and number of pulses in single train . Consuming current by Tesla (Katcher) is low, and pumping 50th harmonica via yoke generally doesn't stress so much push-pull transistors. Gaining current on Grenade output is now 7 amperes and voltage is about 200-211 volts. Light bulbs and Factory Power Supply Unit well work with this output.

Now about gaining more output:

1. The coil was connected only through the full bridge rectifier with high-speed high- amperage diodes with fast recovery times. Coil is 40m Grenade.

2. It is necessary for your device to work properly use only ½ period from Tesla (Katcher) work. Otherwise the Tesla will take away what she has gave back!!!!

Therefore you should put the high-speed high-amperage diode (or parall diodes) from the Earth-Grounding to Grenade end (40m). Akula did it on at receiving side.  He cut off one half of sine on the reception side. Therefore Tesla. Nobody knows it and fight to this day, but bugger,  it doesn’t work. It is also clear why!! To you it is necessary to shake a swing in the energy receiving coil. Swing is «Electron pudding mass». Exactly there you «push pudding» conducting electron current. By the way,for more surplus sink from the Tesla and also for frequency setup Akula  simple used a small light bulb. As in his schematic Inductor was galvanic decoupled from whole device, his small light bulb has served as resistive load for surplus sink and aimings of backEMF sink.  You could not put small light bulb, but you mustn't strongly overdrive Tesla. It isn't necessary!! Always remember that current submits to voltage. I see it from experiments that I have done 2 years ago.
 
Further important:
The diode on a reception side of the Grenade coil remove ½ half-cycle sine and thus we swing  oscillations without slowing down them by negative period of Tesla. Too many people doesn't know it and continue roll molding. That is why Roman (Akula) has said that grounding consume some power... That's right!! Because it, he zap pulse at  ½ period on reception side which is grounded. It is visible on all his devices! I long guessed why he was applied that method and understood that because is so simple and so easy – just  select properly  HV diodes. As any kind of  interference at such frequencies like in Tesla case will lead direct to not correct operation. In other words to cut off a half-cycle not it will turn out. A Kapa resolved this issue by a spark-gap and rectifiers on LF frequencies. There it is simpler and simpler, but it need more wires.... On the German device, Akula used small diodesl, Tesla ws far away, his cable grounding was long. By the way it is equal to Tesla secondary length!!! You shoudn't forget about grounding.... On this device it is the main thing and without good support (grounding) WILL NOT WORK.  Again you shouldn't forget that in this device dangerus high voltages and high currents  were obtained. As you know, HV moves even in the air. For this reason quality grounding is simple necessary part. Plus correct standing-wave (filed)resonance and most important safety....

As that so.....

Best Regards
Physicist Engineer Enjoykin2017
Moscow Russia
Planet Midgard Earh
Galaxy God Perun´s Road
(Milky Way in american interptretation)


ps: I am very tyred from some NATO-MEGA-HORCE-SCIENCE-TROLL to answer at your further questions so my best recommendation is my good Czech friend Good Man High Grade Engineer Verpies. !! Ask him !!

ps2: «Мы нашли причину... И убили её. Но ваше зло неподвластно нам. Оно другое... Так же, как другие и вы. И не всегда чужое добро может оказаться добром для вас. Вы должны найти сами свою причину. И уничтожить её, — он мягко положил руку мне на голову и в меня заструился чудесный покой... — Прощай, Человек-Светлана... Ты найдёшь ответ на свой вопрос. Покоя тебе...».

Светлана де Роган-Оболенская-Левашова, «Откровение».

Verpies and AlienGrey cant stand me telling how to do it, first. Later, after they have maligned, me, they will claim they have discovered the same thing, first, with no reference to me.

It is not acceptable because you clearly have spikes (marked in red) above typical V_{GS_th} (marked in yellow) which results in spurious MOSFET turn-ons.
The -4.8V negative excursions are not a problem (marked in green).

P.S.
Lookup in the datasheet what the V_{GS_TH} parameter is for your MOSFETs.

Verpies,
Your right thanks, i didn't notice those red ones

The Vth = 2    -    4V.           ....so those peaks let the mosfet switch. (IRFP260M)
I ll see that i have several short peaks of (5 total) of 250ns,..... vew of them are 4V.
 the fet with the longest wire to gate has the highest peaks.(wich are also present but stay around 2 V, some even 2,2V)
Unfortenatly the Treshold voltage of 2,2V at 250ns would also trigger the fet,... or is it to fast in order not being able to charge the gate sufficient?

I consider placing the mosfetdrivers as close as possible to the mosfets will give most positive effect on the spike elimination.
Or is there another simple way for elimination?

I updated the PDF attachment above.  So just download it again.

I thought some of you were investigating the spark idea ? How is it that everything we see that appears to work, uses that phenomena, strange that! 'ain it',  'eah'! 

The Turn-On Delay time is 17ns for this MOSFET and the Rise Time is 60ns (with 10V gate pulse and 1.8Ω gate resistor) so 250ns is plenty enough to turn-on this MOSFET, but in reality the current in that spike is probably not sufficient to fully turn it on.  However a halfway turned on MOSFET is not happy either because its Source-Drain resistance becomes several Ohms and leads to Joule heating according to i²R.
Gluing the drivers to the MOSFETs will help a lot, but you must also shield the high-impedance inputs of the drivers with a twisted pair or mini-coax.  The drivers should have low ESR (non-electrolytic) capacitors soldered right across their supply pins, too.  Ferrite beads or mini-chokes are recommended too, before these capacitors.
As usual, shielding, short wires and Starpoint grounding are a must, too.

Also, you might want to use other techniques described in the attachment below.

hi verpies and apecore,

There is a simple reason why IGBT is recommended over mosfet which i had found out the hard way maybe 6...8 months ago.Even the 1.2kv silicon carbide mosfet can be destroyed.
Some of us may recall that "mosfet is able to function well at high frequency" and IGBT is more suited for low frequency.
IGBT eg:50N6S2(There are better IGBT created and can be used) is the best option if we don't want kacher or tesla coil high frequency to effect yoke driver.
It is the main reason why Akula used IGBT instead of Mosfet.But i don't care if you don't buy my story.

If we don't want high frequency spike in IGBT gate just put 1 or 2 tiny ferrite bead through IGBT gate pin and IGBT is place close to  mosfet driver ground and output.
It's better to ignore/supress spikes with beads than to implement unwanted circuit to recover spike.Not forgetting snubber circuit the usual Akula design eg:youtube :sanjev21  pwm circuits

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I have just drawn  a version 2.0 of my high efficiency tesla driver circuit with interrupter capability(Prototype) for upload in my youtube channel:sanjev21 within 48hours.

Imagine this using 2.0 circuit  at 12.8volts supply i am able to achieve 9.5KVpp and at 24volts i am getting 12KVpp at 110 turns output just below 2Mhz (test tesla coil -Akula design with high Q winding at top half).

No more high voltage supply eg:60volts ...100volts or 150volts needed.Fewer winding is needed to achieve the desired voltage at driver yoke/toroid.

This prototype circuit base on my experimental knowledge is the highest efficiency tesla driver ever created in the internet and this information i can give for free in due time.
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I do find it strange no one ever mention  "reactive power" in this forum or maybe i might have overlook in comments.