Author Topic: 2 Mega Hz Class-E style Tesla Coil  (Read 2279 times)

Offline NyaaX_X

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2 Mega Hz Class-E style Tesla Coil
« on: May 04, 2023, 10:03:23 AM »
Hello friends~!!
This is my first topic of Tesla coil here . My friend encouraged me to come here and post my questions . He made a lot of great Coils like this ~ https://highvoltageforum.net/index.php?topic=2423.msg17925;topicseen . He is outstanding .

Then SORRY for that I don't have a oscilloscope these days so I cannot fix mistakes from my circuit . But I hope I can learn some new things and take advices to improve it . Also my english is not good .

This circuit is from Mr. Richieburnett's 4MHz HFSSTC http://www.richieburnett.co.uk/hfsstc.html ,but I just want to make it easier for me . So I only make a 2MHz version . But when it turn on I realize that the power Class-E stage waveform is not good . There are many spikes and the shape is not like a classic Class-E amplifier . I thought the classic one the Class-E mountains are rise rapidly but slowly-softly go back to 0V . But mines are symmetry . I have no Idea how to solve them . T T ...

PS. Two of the image is my power stage VDS and VGS . And one is that I'm saying the shape of classic Class-E waveform , and another one is a tuning trobleshooting example from the internet .

Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #1 on: May 04, 2023, 10:08:15 PM »
Quote
This circuit is from Mr. Richieburnett's 4MHz HFSSTC http://www.richieburnett.co.uk/hfsstc.html ,but I just want to make it easier for me . So I only make a 2MHz version . But when it turn on I realize that the power Class-E stage waveform is not good . There are many spikes and the shape is not like a classic Class-E amplifier . I thought the classic one the Class-E mountains are rise rapidly but slowly-softly go back to 0V . But mines are symmetry . I have no Idea how to solve them . T T ...
Pure class-E asymmetry comes from damping (load resistance).  For a Tesla coil, load comes from the arc.  A perfectly efficient class-E circuit with no load will have a perfectly symmetric Vds waveform.
In other words, your Vds waveform looks fine to me.  As you increase power and arc grows, you should see more asymmetry.
The other way to get asymmetry is with class-EF where a second L/C resonant frequency creates the soft corner as Vds drops back to 0V.  I read that class-EF is used for wireless charging and other high-frequency switching supplies because efficiency is higher at light load than pure class-E.  I have no personal experience with class-EF, only what I've read.

Quote
Then SORRY for that I don't have a oscilloscope these days so I cannot fix mistakes from my circuit.  But I hope I can learn some new things and take advices to improve it.
It will be difficult to improve anything without an oscilloscope.  Even increasing power (increasing input voltage) of your existing design will be risky.  As the Vds falling edge corner rounds, may extend with width of Vds pulse enough to not maintain class-E operation.  Scope is the best way to see what is happening.  Otherwise you run the risk of destroying your FET.

Quote
Also my english is not good.
Your English is infinitely better than my Chinese. :)

Hopefully you can get access to a scope before long.  I'd also recommend simulating your circuit for better understanding and for experimenting without risking any physical part damage.  There are several free simulation programs, both on-line and download.  My favorite is LTSpice.  Old version 4.23j or earlier performs better than newer versions after Analog Devices purchased Linear Technology.  Appears to still available a couple places:
    https://www.downloadsource.net/1762206/ltspice-iv/
    https://ltspice-swcadiii.updatestar.com/en
If you can't get to this old version, the latest from Analog Devices is still fine for most uses.

To go along with LTSpice, there is a small stand-alone tool to generate VDMOS models from FET data sheet parameters and graphs.  It can be found at groups.io, though you'll need to create a login to access:
    https://groups.io/g/LTspice/filessearch?p=name%2C%2C%2C20%2C1%2C0%2C0&q=mostool.exe
LTSpice includes a reasonable number of built-in FET devices.  However, for SiC or any other newer part, you will need to either generate a model or find one with an internet search or from vendor.

LTSpice simulation schematic for my 13.56MHz SSTC is posted on this forum:
    https://highvoltageforum.net/index.php?topic=1638.msg12549#msg12549
« Last Edit: May 04, 2023, 11:43:52 PM by davekni »
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #2 on: May 05, 2023, 04:43:34 AM »
Thank you Dave !!

So my case is nearing to the correct Class E waveform ? But what about the spikes on the curve ? I had only one probe so I cannot measure the VDS and VGS in the same time.. Maybe the Cds capacitor is too large or something . But I think on my waveform . The spikes appear while the MOSFET turn off , the VDS is rising . So that might be the " Miller capacitor " problem ? I am not sure which one is for my question .

And another thing is the primary coil is heating . So do the secondary coil . Is this the sign that my circuit is not well tuned ? That I use a 14 AWG multi-core wire to be the primary and 0.25mm diameter copper wire and a gray PVC pipe to wind the secondary , But some information says that if PVC not pure and add some carbon in it , even some of them point that PVC has a lot RF dielectric loss , so maybe I have to rewound a secondary on a quartz-glass or cardboard tube ?

Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #3 on: May 05, 2023, 06:20:31 AM »
Quote
But what about the spikes on the curve ? I had only one probe so I cannot measure the VDS and VGS in the same time.. Maybe the Cds capacitor is too large or something . But I think on my waveform . The spikes appear while the MOSFET turn off , the VDS is rising . So that might be the " Miller capacitor " problem ? I am not sure which one is for my question .
Yes spikes do appear to be Miller capacitance.  Lower impedance gate drive is needed to fix that.  GDT looks like the biggest issue (largest contribution to gate drive impedance).  You might find this tutorial helpful:
    https://highvoltageforum.net/index.php?topic=1854.msg13949#msg13949

Quote
And another thing is the primary coil is heating . So do the secondary coil . Is this the sign that my circuit is not well tuned ? That I use a 14 AWG multi-core wire to be the primary and 0.25mm diameter copper wire and a gray PVC pipe to wind the secondary , But some information says that if PVC not pure and add some carbon in it , even some of them point that PVC has a lot RF dielectric loss , so maybe I have to rewound a secondary on a quartz-glass or cardboard tube ?
Not a tuning issue.  First, I presume "multi-core" means stranded wire.  That is not a good choice for 2MHz windings.  (Somewhere on the forum I posted an explanation of why, but don't have time to search for that at the moment.)  Second, yes, PVC dielectric loss may be contributing.  (I'm guessing gray is not made with carbon for coloring.  Black sometimes is.  But PVC is still not a great choice even if not carbon-filled.)  Yet higher frequency coils I've seen (6MHz and up) are usually mostly air-core with some minimal support structure.  I use mica sheets for support.  At 2MHz, polypropylene or polyethylene would likely be fine.
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #4 on: May 05, 2023, 06:52:49 AM »
Thank you David~~

But I have still no Idea about the way to advance my GDT , the waveform of GDT to MOSFET seems quite fine Before turning on power stage ... I use N49 TDK ferrite core

And yes I use stranded wire , I was believing that it can decrease the skin effect but it keep getting hot.
« Last Edit: May 05, 2023, 07:15:55 AM by NyaaX_X »

Offline 曹靖

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #5 on: May 05, 2023, 08:23:31 AM »
Thank you David~~

But I have still no Idea about the way to advance my GDT , the waveform of GDT to MOSFET seems quite fine Before turning on power stage ... I use N49 TDK ferrite core

And yes I use stranded wire , I was believing that it can decrease the skin effect but it keep getting hot.
蓝色磁环大多是 铁粉磁环或者铁硅铝磁环它们适合做扼流圈而不是GDT~射频GDT最好使用镍锌磁环~镍锌磁环大多是没有染色的黑色磁环~你可以用万用表电阻档位测量一般是不导通的~如果测量磁环表面有几十到几百欧姆的电阻那就是猛锌磁环~而猛锌磁环大多是绿色的也有黑色的~猛锌磁环适合做DRSSTC和SSTC的GDT或者电流互感器~猛锌磁环的居里温度点低不适合做射频应用~镍锌磁环距离温度高广泛应用在射频领域
曹靖

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #6 on: May 05, 2023, 08:41:21 AM »
Yes , in this circuit I use TDK N49 MnZn ferrite core , the temperature of them while running isn't rise high significantly I think , and the blue color is epoxy that manufacturer apply on it . Maybe 2MHz to these cores is OK ?

是的,在這個電路裡我使用的是 TDK 的 N49 錳-鋅 鐵氧體磁環,在運行時我認為沒有發現其溫度有明顯升高,那個藍色的環氧樹脂塗層是製造商加上去的。可能2MHz對於這些個磁環還算可以接受?

Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #7 on: May 05, 2023, 06:44:47 PM »
Quote
But what about the spikes on the curve ? I had only one probe so I cannot measure the VDS and VGS in the same time.. Maybe the Cds capacitor is too large or something . But I think on my waveform . The spikes appear while the MOSFET turn off , the VDS is rising . So that might be the " Miller capacitor " problem ? I am not sure which one is for my question .
Yes spikes do appear to be Miller capacitance.  Lower impedance gate drive is needed to fix that.  GDT looks like the biggest issue (largest contribution to gate drive impedance).  You might find this tutorial helpful:
    https://highvoltageforum.net/index.php?topic=1854.msg13949#msg13949

I answered a bit too hurriedly last night (morning your time).  A more likely reason for Vds spikes/ringing is inductance of connections from FET source and drain to 4nF resonant capacitor.  That wire/lead inductance combined with FET Cds forms a high-frequency (ring frequency) resonant circuit.  That Vds ringing couples back to Vgs through two mechanisms.  One is Miller capacitance.  Other is FET source connection inductance, the part that is common between Vds and Vgs.

Minimizing FET lead and wire inductance is the first step.  Vgs ring can be further reduced by connecting GDT output leads as close to FET body as possible.  Both of these can be seen in my half-bridge tutorial:
    https://highvoltageforum.net/index.php?topic=1324.msg9795#msg9795
General parallel-plane interconnect can be applied to class-E as well.

Quote
Yes , in this circuit I use TDK N49 MnZn ferrite core , the temperature of them while running isn't rise high significantly I think , and the blue color is epoxy that manufacturer apply on it . Maybe 2MHz to these cores is OK ?
Your GDT core and number of turns looks fine.  I'd still suggest winding as two parallel (or twisted) wires, primary and secondary wires adjacent and wound together as in my tutorial.  That reduces leakage inductance, so will reduce the Vgs ringing coupled from drain through Miller capacitance (Cdg) by lowering Vgs drive impedance.  Oh, I now see that your GDT is 2:1.  In that case, wind two twisted pairs as in tutorial with 6 turns.  Connect two primary windings in series for 12 turns.  Connect two secondary windings in parallel for 6 turns.

Quote
And yes I use stranded wire , I was believing that it can decrease the skin effect but it keep getting hot.
To reduce skin effect, you need litz wire.  Litz wire is stranded wire where each strand is individually insulated.  At 2MHz, requires very fine litz wire, made of bundles of 46AWG insulated magnet wire to be helpful.  Uninsulated strands are worse than solid wire.  Even coarse insulated strands can be worse than solid.
« Last Edit: May 05, 2023, 06:50:25 PM by davekni »
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #8 on: May 06, 2023, 04:59:06 AM »
Thank you very much ~ David ^ ^ Please feel free when answer me something ~

I'm wondering if those spikes can be lot of loss in my circuit . I just cannot generate that powerful arc like Mr.曹靖 https://highvoltageforum.net/index.php?topic=2423.msg17818#msg17818 . His projects are beautiful and crazy . Especially when I realize the primary coil , secondary coil and MOSFET are heating .. They're not very hot , maybe around 50 celsius degree .

And saying about that GDT , that way I wound wire is more convenient to tune for resonant gate drive .


Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #9 on: May 06, 2023, 06:13:31 AM »
Quote
And saying about that GDT , that way I wound wire is more convenient to tune for resonant gate drive .
OK, I hadn't paid attention to your circuit details, that your gate drive was resonant.  I'm used to seeing resonant drive at higher frequencies.  If you resonant circuit relies on GDT leakage inductance, then there is no way to get around that.  Only option that comes to mind to reduce gate drive impedance for your circuit is to move the parallel resonant capacitor (680pF) to the output side of GDT, directly at FET to minimize stray inductance.  That would require retuning and a significantly larger cap value given 2:1 GDT.  May be better to leave gate drive alone.  Focus on minimizing stray inductance on FET drain-source-caps.
The flame-like behavior of HFSSTCs appears to require ~9MHz or higher.  I've built two HFSSTCs.  First was at 6.78MHz (lowest ISM frequency).  It behaved somewhat like a normal HFSSTC and somewhat like a CW SSTC.  Second is at 13.56MHz (more standard ISM frequency).  It behaves better.  Both use SiC FETs (as does the one you link to) with large heat sink and fan blowing air on sink.

Quote
I'm wondering if those spikes can be lot of loss in my circuit .
Yes, I'd guess they are a cause of significant loss (heating of FET).
« Last Edit: May 06, 2023, 06:15:38 AM by davekni »
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #10 on: May 06, 2023, 07:40:14 AM »
Oh my those spikes... ok I'll try another layout when I get an oscilloscope .Or maybe my tuning 4nF Cds of irfp460a is not correct for this tuning . The 680p capacitor is the driver stage class-E tuning capcitor , , , not the power stage waveform I post in thread . The image is  from irfp460a Vgs and Vds .

thank you very much to you for answer me a lot ~

Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #11 on: May 06, 2023, 08:19:47 PM »
Quote
The 680p capacitor is the driver stage class-E tuning capcitor , , , not the power stage waveform I post in thread . The image is  from irfp460a Vgs and Vds .
Yes, I understood correctly.  (BTW, if you add labels such as "C1", C2", etc to your schematic then discussing specific parts is more clear.  Since I see only one 680pF capacitor, it is unique.  In case you had two 680pF capacitors, labels would make it easier to refer to one or the other.)

Quote
Or maybe my tuning 4nF Cds of irfp460a is not correct for this tuning .
The spikes/ringing are not caused by incorrect tuning (by wrong value for 4nF).  However, some capacitors have more parasitic series inductance than others.  Your caps are probably fine.  But it is good if possible to check capacitor data sheet for series inductance (or self-resonant frequency from which series inductance can be calculated).

I just noticed in the title picture of your video there appears to be black arc marks along top of your PVC coil form.  Any idea how those were made?  Makes me even more suspect that coil form material is not good.  I recommend winding a new coil with solid primary wire and a better core material.  Mostly-air core is one option, such as crossed pieces of flat plastic or mica or glass rod posts or ...  Or a low-loss plastic such as polypropylene or polyethylene.
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #12 on: May 07, 2023, 04:33:25 AM »
OK~ Because I think there're not much components in the schematic so I deleted the C1 C2 .. etc

The black marks is Lichtenberg , I guess that discharge needle topload (soldering iron tip) turned very hot and pass heat to PVC and it flash fire up . The arc go in this path and burning ... After that I put two piece of silicon wire peel between them to against the heating . The other issue is I use 0.25mm copper wire to wind this 2MHz coil , that is not possible for me to make a no skeleton air  core . Maybe I can make a cross piece square secondary , 曹靖 advices me . Or just find a good cardboard tube or quartz-glass tube in the future ~

PS. On my Board I put a TVS diode between MOSFET and 4nF capacitors so more distance .. = = And I don't have a autotransformer so if the pri&sec coupling is bigger , when 72V supply on the voltage peak will have chance to destroy my MOSFET .
« Last Edit: May 07, 2023, 04:52:30 AM by NyaaX_X »

Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #13 on: May 07, 2023, 09:21:39 PM »
Quote
Maybe I can make a cross piece square secondary , 曹靖 advices me . Or just find a good cardboard tube or quartz-glass tube in the future ~
I would not recommend cardboard unless you live in a very dry climate.  Glass should be OK.  Perhaps easier and better:  Do you have any suitable sized plastic bottles around?  Most bottles for vitamins or shampoo or many other household items are made from polyethylene.  Water and soft drink bottles are often polyester, which would also be fine.  Not quite as low dielectric loss as polyethylene, but better than glass.  Advantage of glass would be ability to handle higher temperature if wire gets hot.  Square secondary on crossed pieces of plastic or mica is also a good option.  (One more thought:  Do you happen to have access to any roll cores for tape or other film products that are long enough?  My 480kHz QCW coil uses a large roll core.  I'm not certain what plastic is used, but roll cores seem to work well.)

Quote
And I don't have a autotransformer so if the pri&sec coupling is bigger , when 72V supply on the voltage peak will have chance to destroy my MOSFET .
LTSpice or other analog simulation is a great way to see what parameters affect peak voltage.  Low coupling isn't the only option to achieve any desired FET peak voltage.
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #14 on: May 08, 2023, 01:24:54 AM »
Bottles or containers will not be my choice..cause their shape usually not even or too thin or too soft . I afraid that wire would be lossen after heating ... mica , this material is not familiar to me . And I don't think my skill and tools are good enough to make the cross one or something not a tube manually . I believe that tubes is more stable and easy to wind nicely especially for thin wire .

And saying about SPICE , then sorry for I am not good at this .. I don't know the parasitic parameter values . That is the biggest problem to me . I didn't learning well and not normaly profess to electronic science .. And when I make these project I always guess and try , there are many knowledges are my shortage ... sad QAQ

The turning on peak voltage is a trouble , I used to use ucc37322 to make Class-E like https://www.stevehv.4hv.org/classEsstc.htm or https://highvoltageforum.net/index.php?topic=1014.0 And there is the same problem that when I sent 72 V or even low voltage like 48 V into power stage (I turn on driver stage before this ) MOSFET have a chance to be broke down ... I don't know what lead it . But if I use a low voltage to start and then boost up I think more coupling is fine and the arcs are truely more powerful .
« Last Edit: May 08, 2023, 01:28:06 AM by NyaaX_X »

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #15 on: May 21, 2023, 06:12:29 AM »
Here is the Zip file. My Vds are not well tuned. This is a test. I was trying to make them close to my real experiment. But still wired.
« Last Edit: May 21, 2023, 06:58:44 AM by NyaaX_X »

Offline davekni

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #16 on: May 22, 2023, 04:19:37 AM »
Quote
But still wired.
Did you mean "wired", or "weird"?  Presuming "weird", what is unexpected?

Finding reasonable parameters for simulating arc load is one of the hardest parts of Tesla coil simulation.  Arc parameters change as power changes and over time for interrupted coils.  For 2MHz, V_Sec seems too high to be realistic.  So I'd suggest increasing arc resistance (series resistance of C6).  Preferably, remove series resistance from C6 and add as separate resistor in series with C6.  5k or 10k ohms is likely more realistic.  Then tank capacitance will need to drop to maintain class-E operation.
David Knierim

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #17 on: May 22, 2023, 04:55:48 AM »
Quote
Did you mean "wired", or "weird"?  Presuming "weird", what is unexpected?
Sorry for mistype. It's "weird"

I am trying to place all visible components on my board into simulation so the value is mostly close to real circuit. And the waveform is still not match the real result. Now the .step command is helping me guessing some of those coupling k and parasitics.
« Last Edit: May 22, 2023, 12:17:33 PM by NyaaX_X »

Offline NyaaX_X

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #18 on: June 27, 2023, 07:10:30 AM »
I'm thinking if I add a spikes absorbing part into my circuit. Maybe one of the problems can be solved. I use 72 V power supply the power ClassE stage. But if my primary coil coupling too much to secondary. Sometimes the MOSFET will break down when tunrning on. Wait . I see that the Class E waveform will be cut a little bit when the voltage on that 100n Cap in that protection circuit drop after the circuit running stably.
« Last Edit: June 27, 2023, 10:15:36 AM by NyaaX_X »

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Re: 2 Mega Hz Class-E style Tesla Coil
« Reply #18 on: June 27, 2023, 07:10:30 AM »

 


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[Electronic Circuits]
Anders Mikkelsen
March 26, 2024, 01:41:49 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 26, 2024, 04:48:22 AM
post Re: Re-chargeable 1.5 volt lithium ion AAA batteries
[General Chat]
MRMILSTAR
March 26, 2024, 04:16:37 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 26, 2024, 04:16:24 AM
post Re: Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
davekni
March 26, 2024, 04:13:02 AM
post Re: CM400 Induction Heater
[Electronic Circuits]
davekni
March 26, 2024, 04:00:43 AM
post Re: Re-chargeable 1.5 volt lithium ion AAA batteries
[General Chat]
davekni
March 26, 2024, 03:19:18 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
thedoc298
March 26, 2024, 01:50:42 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 25, 2024, 08:05:02 PM
post Re: Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
Mads Barnkob
March 25, 2024, 07:41:29 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 25, 2024, 06:45:46 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 25, 2024, 05:44:25 PM
post Re: CM400 Induction Heater
[Electronic Circuits]
Anders Mikkelsen
March 25, 2024, 04:47:17 PM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
March 25, 2024, 04:27:22 PM
post Re-chargeable 1.5 volt lithium ion AAA batteries
[General Chat]
MRMILSTAR
March 25, 2024, 03:57:34 PM
post Re: CM400 Induction Heater
[Electronic Circuits]
markus
March 25, 2024, 02:06:41 PM
post Re: Odd MOSFET Driver Behavior
[Solid State Tesla Coils (SSTC)]
KrisPringle
March 25, 2024, 04:43:25 AM
post Re: Odd MOSFET Driver Behavior
[Solid State Tesla Coils (SSTC)]
davekni
March 25, 2024, 02:39:40 AM
post Re: Odd MOSFET Driver Behavior
[Solid State Tesla Coils (SSTC)]
KrisPringle
March 25, 2024, 12:47:09 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 24, 2024, 07:36:32 PM
post Re: My completed 14-stage Cockroft-Walton voltage multiplier
[Voltage Multipliers]
Alberto
March 24, 2024, 07:27:24 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 24, 2024, 04:25:23 AM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 23, 2024, 10:47:35 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 23, 2024, 09:30:21 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 23, 2024, 04:34:31 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 23, 2024, 03:04:25 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 23, 2024, 01:38:34 PM
post Re: capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
MRMILSTAR
March 23, 2024, 04:20:03 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
davekni
March 23, 2024, 12:54:30 AM
post Re: Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
davekni
March 23, 2024, 12:05:57 AM
post capacitor and diodes. Voltage values for a CW
[Voltage Multipliers]
Alberto
March 22, 2024, 11:45:03 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
OmGigaTron
March 22, 2024, 11:30:09 PM
post Smoke Screen Machine Protect 950 XP - Teardown of a Smoke Cannon!
[Electronic Circuits]
Mads Barnkob
March 22, 2024, 10:20:35 PM
post Re: Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
Benbmw
March 22, 2024, 09:21:13 PM
post Re: What actually kills MOSFETs?
[Beginners]
AstRii
March 22, 2024, 03:37:11 PM
post What actually kills MOSFETs?
[Beginners]
FPS
March 22, 2024, 05:09:20 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 22, 2024, 03:57:54 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 22, 2024, 02:59:25 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 21, 2024, 06:31:42 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
rikkitikkitavi
March 21, 2024, 03:08:01 PM
post Re: [WTS] IGBT, Ferrite, Capacitors, Tools, PSU, Industrial components and parts
[Sell / Buy / Trade]
Mads Barnkob
March 21, 2024, 01:37:32 PM
post Re: Difference between these transformers
[Transformer (Ferrite Core)]
Alberto
March 21, 2024, 11:42:07 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 21, 2024, 04:09:14 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 21, 2024, 02:15:31 AM
post My Homemade Structural Analysis X-Ray Machine
[X-ray]
Luca c.
March 21, 2024, 01:35:40 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Saattvik24
March 20, 2024, 10:40:00 PM
post Re: Difference between these transformers
[Transformer (Ferrite Core)]
Mads Barnkob
March 20, 2024, 08:03:41 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Mads Barnkob
March 20, 2024, 07:51:57 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
March 20, 2024, 10:39:47 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
March 20, 2024, 04:09:59 AM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 20, 2024, 01:13:23 AM
post Re: Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Keybored
March 20, 2024, 12:45:16 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 20, 2024, 12:30:30 AM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 19, 2024, 11:12:24 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 19, 2024, 09:47:49 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 19, 2024, 09:44:19 PM
post Phase Lead Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Saattvik24
March 19, 2024, 06:52:09 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 19, 2024, 05:02:44 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
Mads Barnkob
March 19, 2024, 05:01:41 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
March 19, 2024, 04:31:02 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
March 19, 2024, 03:59:54 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
March 19, 2024, 06:41:39 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
davekni
March 19, 2024, 04:05:49 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
OmGigaTron
March 18, 2024, 09:08:35 PM
post Re: Can I Trust This Super Cheap Site?
[General Chat]
2020-Man
March 18, 2024, 09:07:35 PM
post Re: Can I Trust This Super Cheap Site?
[General Chat]
Twospoons
March 18, 2024, 08:57:06 PM
post Re: Can I Trust This Super Cheap Site?
[General Chat]
MRMILSTAR
March 18, 2024, 03:51:33 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 18, 2024, 02:59:46 PM
post Re: 160mm DRSSTC II project | Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Late
March 18, 2024, 02:33:25 PM
post Can I Trust This Super Cheap Site?
[General Chat]
2020-Man
March 18, 2024, 11:02:12 AM
post Re: Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
Twospoons
March 18, 2024, 02:36:11 AM
post Re: Best forum for vacuum tube amplifiers?
[General Chat]
Mads Barnkob
March 17, 2024, 07:42:55 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Michelle_
March 17, 2024, 04:15:14 PM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Michelle_
March 17, 2024, 05:05:04 AM
post Re: Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
davekni
March 17, 2024, 04:50:51 AM
post Re: 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Twospoons
March 17, 2024, 04:45:17 AM
post 2x Panasonic Inverter Microwaves - what to salvage, dangers?
[General Chat]
Michelle_
March 17, 2024, 04:17:51 AM
post Where's all this voltage coming from?
[Spark Gap Tesla Coils (SGTC)]
Terry
March 17, 2024, 01:29:32 AM
post Re: DRSSTC Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
March 17, 2024, 12:33:06 AM

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