Tesla Music Coil Troubleshoot

[unconsciou5]

Hey ive build a Music Tesla Coil Setup,
this was the base project i am trying to imitate https://easyeda.com/sparpet79012/Mini_Tesla_Coil_musical-14c2ac0595244af9939819ccc8793af7
i have made some modifications - visible in the attachment

Sadly it doesnt work as planned and i dont get any plasma arcs at the top.
My system draws about 1 Amp at 18V and i do see and hear the frequency of the music input on the LED2 (before the secondary coil)
I have already tried to replace R2 with a potentiometer or changing the direction of my primary coil, but nothing helped.
From here it gets very hard for me to troubleshoot any further. (i have tripple checked all the connections)
Maybe there is something wrong with my secondary coil? (ive tried different turn ratios with the primary, with or without topload (needle), and my coil outputs a magnet field when i connect it directly to my powersupply [0.12A at 30V] so it should be fine i guess.
Please let me know things that could be critical or would explain the behaviour.
thank you very much already

[prabhatkumar]

You really wouldn't get any Sparks at 18v. And it's good that you can atleast hear the music, means nothing is wrong with the connections. And don't turn the potentiometer all the way up to get bigger Sparks, you are quite close to the gate source breakdown voltage of the irfp260 used here. And also turning it all the way up you will get lot of heat. If you just want to see some sparks, then probably you can try putting a single turn and then give it a shot.Also put the needle there, it's I think important to see the sparks. But I take no responsibility of your MOSFET here!!. It gets terribly hot. So preferebly have it mounted on a heatsink and also definitely a fan.
And can you give the dimensions of your secondary?. If you really have even a small coil with that number of turns , then building a proper half bridge is worth it

[unconsciou5]

You really wouldn't get any Sparks at 18v

i mean its just the input voltage, the circuit should work just fine with that since the output voltage should be huge

yes, ive recognized the heat problem, its mounted to a heatsink and i am careful with that (i will apply a more powerful heatsink later)

And can you give the dimensions of your secondary?

my dimensions are 14cm in lenght (effective) and 3.3cm Ø. i have used 0.1mm coated copper wire (https://www.reichelt.de/100g-kupferlackdraht-auf-spule-0-10mm-cul-100-0-10-p57176.html)
I had the idea that its might too thin isolated to carry the high voltage - could this be possible? Since ive picked the thinnest available

building a proper half bridge is worth it

sounds like a good suggestion but i dont actually know how it works since i just know them from motors
but i can read into that if necessary

[Mads Barnkob]

Hi and welcome to HVF!

Are you sure this circuit works? I do not see any links to pictures or video from the URL you posted.

The circuit seems to borrow key elements from the slayer exciter and the single transistor flyback transformer driver circuits. R1, R2 and Q1.

I am not sure why R3 and R4 sits in that configuration for 9KOhm. LED2 and Q2 seems to form the feedback and drive frequency, while Q1 is driven directly by the audio source, seems like a horrible drive scheme that will keep the poor MOSFET in its linear region most of the time.

I really suggest making a singing arc flyback transformer instead: http://kaizerpowerelectronics.dk/high-voltage/555-audio-modulated-flyback/

or build a half-bridge SSTC with audio interrupter like this: Coil and bridge from here: and audio interrupter from here: http://kaizerpowerelectronics.dk/tesla-coils/kaizer-sstc-i/ and http://kaizerpowerelectronics.dk/tesla-coils/kaizer-sstc-ii/ or http://kaizerpowerelectronics.dk/tesla-coils/musical-sstcdrsstc-interrupter/

[unconsciou5]

Are you sure this circuit works?

yes i am sure

/>same setup as
https://electronics.stackexchange.com/questions/299643/tesla-coil-audio-music-player-circuit-analysis

I really suggest making a singing arc flyback transformer

thank you i will look into that, looks like i just need the 555 Timer for that

My goal here for now was to produce a safe very low current plasma arc thats safe to touch and so on.

[acmq]

This schematic has a lot of problems:
LED2 can't be there. It is blocking the feedback. It must be from ground to the base.
LED1 will never light up in parallel with the BE junction. The 10K resistor goes to the base (you can use 100k from the power supply to the base) and the 1k resistor to the LED1.
Remove C1. It is useless. Connect it across the power supply.
The ground of J1 must go to the ground, never the collector.
The connections of J1 and C1 in many other schematics of similar circuits are on the other side of the primary coil. Less bad.
The video link uses the same wrong schematic. Quite surprising that the author didn't notice the errors and obtained some results, probably after modifications.