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    voltage and current waveforms spark gap

    Can anybody post current and voltage waveforms. Could not locate current and voltage waveforms of spark gaps found in ordinary tesla coils. The current avalanches between the electrodes - does this make it exponential as found in pn junction charts?

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    Re: voltage and current waveforms spark gap

    Falstad's animated simulator has a tesla coil in its Circuits menu. The run starts with voltage close to the level where spark occurs (10kV in positive portion of cycle. -10kV in negative portion).

    Click image for larger version. 

Name:	Tesla coil 2 transformer 2 capacitor long n short scope timebase.png 
Views:	5 
Size:	37.1 KB 
ID:	154921

    The simulator portrays current direction and intensity.

    The circuit is in the link below. (I created additional scope traces so that waveforms can be viewed more easily.)
    Click to:
    1) Open falstad.com/circuit
    2) Load schematic in simulator
    3) Run it on your computer

    https://tinyurl.com/y3vkq234

    It's easy to add more scope traces, or change component values. Right-click and choose Edit, View in scope, etc.


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    Re: voltage and current waveforms spark gap

    Quote Originally Posted by BradtheRad View Post
    Falstad's animated simulator has a tesla coil in its Circuits menu. The run starts with voltage close to the level where spark occurs (10kV in positive portion of cycle. -10kV in negative portion).

    Click image for larger version. 

Name:	Tesla coil 2 transformer 2 capacitor long n short scope timebase.png 
Views:	5 
Size:	37.1 KB 
ID:	154921

    The simulator portrays current direction and intensity.

    The circuit is in the link below. (I created additional scope traces so that waveforms can be viewed more easily.)
    Click to:
    1) Open falstad.com/circuit
    2) Load schematic in simulator
    3) Run it on your computer

    https://tinyurl.com/y3vkq234

    It's easy to add more scope traces, or change component values. Right-click and choose Edit, View in scope, etc.
    Can a semiconductor completely replicate the SG operation?



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    Re: voltage and current waveforms spark gap

    You might look at publications from the "gaseous electronics"
    conferences, the folks doing very high voltage power switches
    using gas tubes. I'd bet somebody in that crowd has looked
    at SPICE and/or behavioral modeling.


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    Re: voltage and current waveforms spark gap

    Quote Originally Posted by Zak28 View Post
    The current avalanches between the electrodes - does this make it exponential as found in pn junction charts?
    No, except for the name, it's not the same thing.

    Easiest solution is to simply measure it. Because spark gap mechanisms (plural) are not fully understood. Therefore you can not find a simulation model that is actually useful, in the sense - yes you can simulate some stuff, but your real life circuit will behave very differently than the simulation.

    Quote Originally Posted by Zak28 View Post
    Can a semiconductor completely replicate the SG operation?
    And no to that one too. But you can use semiconductors to switch hv, try have a look at my Marx Generator post here https://www.edaboard.com/showthread....-actually-work

    p.s. I eventually gave up on semiconductors and hv, too much hassle.
    Last edited by Swend; 12th August 2019 at 13:38.


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    Re: voltage and current waveforms spark gap

    Quote Originally Posted by Swend View Post
    No, except for the name, it's not the same thing.

    Easiest solution is to simply measure it. Because spark gap mechanisms (plural) are not fully understood. Therefore you can not find a simulation model that is actually useful, in the sense - yes you can simulate some stuff, but your real life circuit will behave very differently than the simulation.



    And no to that one too. But you can use semiconductors to switch hv, try have a look at my Marx Generator post here https://www.edaboard.com/showthread....-actually-work

    p.s. I eventually gave up on semiconductors and hv, too much hassle.
    Does a spark gap when breaking over make many harmonics?



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    Re: voltage and current waveforms spark gap

    Quote Originally Posted by Zak28 View Post
    Does a spark gap when breaking over make many harmonics?
    Your question does not have a definitive answer. I can make a spark gap produce DC or AC (with or without harmonics) just by (thinking of) moving a wire, so there is really no substitute for a real life circuit. My advise is: learn how to measure voltage and current in a spark gap.


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    Re: voltage and current waveforms spark gap

    For an example of unusual waveforms in Tesla coils, there's the kind that sings:

    "Dueling Banjos on musical Tesla Coils"



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    Re: voltage and current waveforms spark gap

    An ordinary spark gap for an ordinary AC tesla coil doesn't make loads of harmonics?



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    Re: voltage and current waveforms spark gap

    No doubt about it. The purpose of a tesla coil is to "make harmonics", generate high frequency signals up to MHz from a low frequency power source. In so far the question is a kind of stupid. Just look at the spark gap I/V characteristic.

    A different question is if a Tesla generator can be linearly modulated in a certain operation range. You may want to ask specifically.


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