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FrozenGate by Avery

FEELER: Plasma Speaker Kits

Do you have any decoupling caps on the supply?

They need to be something low value, like 0.1 uF or something similar. It may help with noise and stability, if you don't have them there already.
 





Im using a OMRON PSU that was intended for supplying PLC systems so i imagine it would.
 
The decoupling caps Le Quack is talking about have to be within a centimeter of trace of every chip on the PCB, they are not in the power supply. The sharp rise times of oscillation or pulses leads to inductive effects which need to be cancelled out. In my own tests as little as 7mm of trace at above 100kHz is all that is needed to cause ringing on output waveforms. I use tiny MLCC 50v 0.1uF caps directly under the chip on the back of the board directly across the Vcc and Gnd pins and also a 25v 22uF electrolytic within 1cm (overkill).

I would still check your PLL phase adjustment as the primary source of buzz.
 
i could do 90% of the assembly which means assemled PCB, wound primary and secondary coil, PSU included and wired up. The end user would have to just make the connections as i dont ship them connected. I have 2 spare PSU's but they arent cheap.

I dont know what it would be worth either, be a bit more expensive than just in kit form.
 
I'd have to get it pre built depending on overall coins ;) connecting connections shouldn't be a problem) my soldering is shit
 
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you'd be looking at $320 excluding postage, all you would need to do is make the power supply and coil connections.
 
Im fairly new to all this, but regarding the hum problem:
Could you use an isolation transformer (120v in 120v out) to filter any incoming power harmonics of 60hz that might cause hum?
Or maybe a choke filter and/or highpass on the input to the audio source?


I didint get in on the oneTesla, unfortunately. I plan to order one of their kits as soon as they come available again, but it might not be till mid summer or later, or never... So I am looking for similar projects to keep my busy meanwhile. A plasma speaker or a TC capable of a nice jacobs ladder would be fun. I have thought about getting a kit from eastern voltage research, but they are expensive for not coming with the pretty topload or acrylic chassis. I just need to get started on some high voltage project of some form or another to occupy my fascination.


Your builds look awesome. Do you have any recommendations for me? I feel like the microbrute kit from EHVR would be the best kit I can get other than oneTesla, but im new not sure where to look...
 
Hey man,

the kit runs off of 24VDC, so its already been rectified and smoothed by this omron PSU:

4782880.jpg


Dam! i only just got in on the 220VAC kit, they are getting ready to ship them sooon :D

Yeah your right about EVR, there plasma speaker is pretty pricey for what you get, ive sunk a lot of money into my EVR Microbrute -> http://laserpointerforums.com/f60/holiday-project-drsstc-d-78988.html

If i can get the plasma speaker working properly it would make a great, cheaper option to occupy your fascinations with HV :)

The EVR Microbrute is pretty involved, how are your soldering skills?

Are you able to wind the secondary yourself?

Fiddy.
 
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I consider my soldering skills to be excellent, I build and repair audio cables/devices at work pretty regularly for the past couple of years and I have a fantastic soldering station with a vacuum iron =D. An old timer who worked for bell helicopters back in the 60's as a QC inspector was my teacher before he retired last year. Quite the nice lab at work here with a few scopes and analyzers, meters etc.. im a lucky guy

That being said, I'm certainly not excellent at surface mount components, although I can get by. I am planning to wind a small secondary soon here for a baby coil powered by a small 3vdc powered HV xformer from a bug zapper wand. Hopefully its not a big deal. I have patience and am motivated.

Glad to have found you on here, Im enjoying your posts.
 
Hey man,

theres only 1 surface mount capacitor in the kit but ive elliminated it and replaced it with a through hole capacitor now :D Im not the best with surface mount suff either :)

Good stuff! Winding can be very fun if you do it right or very painful if you dont have a good setup!

Cheers!
 
If you get your hum isolated, Id love to get a kit from ya, or at least a spike for another build. If i build a micro brute, would it be possible to change between a full spectrum driver for audio and DR driver for larger sparks and midi control, or do they require significantly different coil setups?

And side note:
Do you live in oz? Aren't laser pointers outlawed there or is that a rumor?
 
Unfortunately DRSSTCs cannot be direct audio modulated like SSTCs can be. So you only get midi/interrupter with a DR.

The reason being is that the addition of a tank capacitor to the primary circuit that makes a DR different from a standard SSTC causes massive circulating primary currents. The transistors have to be precisely controlled in on and off times and limited to a certain number of back to back cycles to prevent explosive hot spots from forming inside the silicon of the transistors. Without this tank cap the primary is nonresonant and forms a current limiting inductor instead, which allows the transistors to run full power freely. Audio modulation requires a free running oscillator (called CW for continuous wave).
 
Thank you for that excellent explanation. I was pretty certain I couldnt do that, but now I actually have a mental picture of the difference. Looks like Ill be building multiple coils, which really was already the plan anyhow.

I am eager to see Fiddy compare the microbrute with the onetesla kit. The main reason I havent got a microbrute ordered yet is because of the value of the onetesla since it has everything I want all at once for the best price, including the midi interrupter, acrylic, secondary, and toroid.
 
I suppose it wouldn't be too hard to make a coil that switches between DR and non-DR with few component changes. AFAIK you'd just need to change the feebdback CT (on secondary for non-DR and on primary for DR), the tank cap and the interrupter. But you could always make the interrupter handle both modes of operation.
 
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