High voltage arbitrary waveforms? How?

Thread Starter

CosmicOrderMachines

Joined Oct 31, 2019
77
I'm curious once more. Through my experiments I've failed to get an intense electric field through my arbitrary waveform. Hence using the tesla coil configuration I've tried to generate the field. I bought an amplifier that does 200watts into 4 ohm and amplified my signal generator with the waveform and fed it into a primary. Nothing on the output. Find resonance and surely I do get a high voltage field appearing, only, its been condensed into a sine wave. How in the world do I get a arbitrary waveform through a coil like this to get me a strong electric field?? Is it A) low voltage high current amplifier that maybe can somehow disregard the need for resonance to make this thing produce a field. B) modulate a carrier wave that is already at resonance? I'm trying to avoid B unless it adds beyond my scope of ability to continue without it.

photo_2021-03-28_19-08-33.jpgscope across a primary
photo_2021-03-28_19-08-35.jpgthe waveform of that scope
photo_2021-03-28_19-08-38.jpgThe 'picked up' voltage from nearby the secondary
 

DickCappels

Joined Aug 21, 2008
7,722
Use a linear amplifier to generate electric fields with arbitrary waveforms.
1617003612104.png

1617003690510.png
Sanyo made (makes?) transistors capable of operating collector voltages of 1800 volts.

Also see U.S. Patent 5396151
 

Yaakov

Joined Jan 27, 2019
3,511
I'm curious once more. Through my experiments I've failed to get an intense electric field through my arbitrary waveform. Hence using the tesla coil configuration I've tried to generate the field. I bought an amplifier that does 200watts into 4 ohm and amplified my signal generator with the waveform and fed it into a primary. Nothing on the output. Find resonance and surely I do get a high voltage field appearing, only, its been condensed into a sine wave. How in the world do I get a arbitrary waveform through a coil like this to get me a strong electric field?? Is it A) low voltage high current amplifier that maybe can somehow disregard the need for resonance to make this thing produce a field. B) modulate a carrier wave that is already at resonance? I'm trying to avoid B unless it adds beyond my scope of ability to continue without it.
When you say “intensive electric field” what exactly do you mean? That is, could you define “electric field”?
 

Thread Starter

CosmicOrderMachines

Joined Oct 31, 2019
77
Sucky part is, ive seen something like it in real life. It used a tesla like configuration. So I'm wondering. Is the only way they did it to modulate a carrier or is there another way?
 

DickCappels

Joined Aug 21, 2008
7,722
Illegal and annoying amounts of RF will be the result.
Whether the fields are illegal, annoying, or dangerous depends on the frequency, amplitude, and local regulations.

I was once given a demonstration of a desktop computer using a single CRT gun and beam penetration phosphors. To get it to change to writing a different color all of the tube's electrodes had to be switched at over 100 Hz. It was a very creative design but the faceplate voltage switching by 10 kV or more at such a high frequency, the hair on the top of my head was flapping in the electrostatic breeze. We opted to not develop it, particularly in view of an emerging European rule regarding ELF fields in desktop displays used in offices. I believe it was not harmful or illegal but it sure was annoying.
 

Thread Starter

CosmicOrderMachines

Joined Oct 31, 2019
77
What frequencies are present in your arbitrary waveform?
Present in it.. The equation to make it looks something like this sin(1.618x+1.618)*sin(2.617x+1.618)*sin(4.235x+1.618)*sin(6.853x+1.618)

Each frequency is golden ratio proportion to the others and all multiplied together to give the arbitrary waveform. The same characteristic "form" is given no matter what frequencies you add in the equation and multiply together, as long as the ratio within remains the same.
 

nsaspook

Joined Aug 27, 2009
8,678
Whether the fields are illegal, annoying, or dangerous depends on the frequency, amplitude, and local regulations.

I was once given a demonstration of a desktop computer using a single CRT gun and beam penetration phosphors. To get it to change to writing a different color all of the tube's electrodes had to be switched at over 100 Hz. It was a very creative design but the faceplate voltage switching by 10 kV or more at such a high frequency, the hair on the top of my head was flapping in the electrostatic breeze. We opted to not develop it, particularly in view of an emerging European rule regarding ELF fields in desktop displays used in offices. I believe it was not harmful or illegal but it sure was annoying.
Totally difference EM radiation situations.

He's in the range of several hundred kHz according to the scope reading. Harmonics could easily be in the broadcast frequency range using broadband amplifiers with thousands of volts at several hundred watts across space to some sort of conductor..
 

Thread Starter

CosmicOrderMachines

Joined Oct 31, 2019
77
Totally difference EM radiation situations.

He's in the range of several hundred kHz according to the scope reading. Harmonics could easily be in the broadcast frequency range using broadband amplifiers with thousands of volts at several hundred watts across space to some sort of conductor..
Well I am running into the issue of resonance at that point. Being the distortion of my waveform. Would happily take any frequency as long as my mission can be accomplished. As well as the the leads of the coil will couple to some gas tubes to make a glow. Not sure if that makes differences. The power you speak of I'm unsure. I'm happy with lower power if that met some regulations that I'm unsure of.
 

Thread Starter

CosmicOrderMachines

Joined Oct 31, 2019
77
Totally difference EM radiation situations.

He's in the range of several hundred kHz according to the scope reading. Harmonics could easily be in the broadcast frequency range using broadband amplifiers with thousands of volts at several hundred watts across space to some sort of conductor..
Related to this, I heard someone mention a similar situation

"RE:""And of course the frequency used must be selected to avoid interfering with anybody who cares""
Not very much. I have measured the field intensity around the 38 mm thick ICP coil - 3000 V/m at inside, 800 V/m at 1 cm distance outside, 300 V/m at 2 cm, 10 mV/m at 1 meter, less than 1 microvolt per meter at 10 meter distance." @Janis59
 

nsaspook

Joined Aug 27, 2009
8,678
Related to this, I heard someone mention a similar situation

"RE:""And of course the frequency used must be selected to avoid interfering with anybody who cares""
Not very much. I have measured the field intensity around the 38 mm thick ICP coil - 3000 V/m at inside, 800 V/m at 1 cm distance outside, 300 V/m at 2 cm, 10 mV/m at 1 meter, less than 1 microvolt per meter at 10 meter distance." @Janis59
My advice to that is to carefully consider the source and situation.
 

BobaMosfet

Joined Jul 1, 2009
1,850
I urge caution to anyone playing with high voltage EM fields- You're playing with energy, and radiating energy through your body, without controlling it using a wave-guide can be dangerous. This is why people don't stand directly in front of a radar dish when it swings around.
 

Thread Starter

CosmicOrderMachines

Joined Oct 31, 2019
77
I urge caution to anyone playing with high voltage EM fields- You're playing with energy, and radiating energy through your body, without controlling it using a wave-guide can be dangerous. This is why people don't stand directly in front of a radar dish when it swings around.
Thanks,

Hopefully I'm not making that much power. Even such high voltages that you get sparks from a tesla coil are too high for me. I need enough to get some plasma excited.
 

Delta Prime

Joined Nov 15, 2019
1,149
Hello there:)
need enough to get some plasma excited.
Bleeding, blistering, discomfort, itching, lumps, numbness, pain, rash, redness, stinging, swelling, tenderness, tingling, or warmth when you turn on the switch is an indication that you are in the plasma field not just the observer.
;)
That's coming from experience in a controlled environment.
 
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