October 28, 2018 by shah in EssayWritings

If you are using a standard NST, there is a significant amount of leakage inductance and capacitance associated with its own secondary windings, so there is a definite resonant frequency associated with the NST itself.The spark gap does interesting things to the spectral content of the current.

The number of cycles of ringing before “significant” decay is approximately equal to the Q of the mode in question.Complicating all of this is that true arcs can present negative differential resistance, and that NSTs are designed to have saturable cores (partly out of economy, partly to provide “free” protective current-limiting). It’s like my input kvalias or the stranger ones, are there and when blocked, they cause pressure. The number of cycles of ringing before “significant” decay is approximately equal to the Q of the mode in question.Complicating all of this is that true arcs can present negative differential resistance, and that NSTs custom essay writers uk
are designed to have saturable cores (partly out of economy, partly to provide “free” protective current-limiting). I am unable to visualize what happens to the voltage level, though it was decreasing in an orderly fashion, at the instant the arc extinguishes.I’m being simplistic here due to my limited technical knowledge; am I close to visualizing what’s happening? jocular sorry for all the typos… I think the pressure at depth would be atmospheric pressure + the average density of the soil/gas (which you would calculate from the soil porosity and the densities of the soil and the atmosphere) times the depth of soil x acceleration of gravity for the planet in question. It acts much like a modulator, actually, interrupting the 60Hz mains power at a rate determined by a combination of the breakdown voltage and the reactances connected to the spark gap (it’s perhaps more intuitively appealing to say that the 60Hz mains power modulates the spark gap current). Related Discussions:Research Helpsoil healthdepth of frost?Pristine air quality, soil qualitySoil ScienceNeed help rigging something to chill soil.To all Members and Guests of The Science Forum living in the Southern Hemisphere.Crop rotationTesting SoilQuestions about Volcanic Soil However, there’s a bit more to it than that, and this is where the fun part comes from. In the absence of any resonant behavior, you’d see sharp — nearly discontinuous — transitions from “off” to “on.” Those fast-rising/falling edges are a signature of very high frequency content.If there are resonances, those sharp edges will excite them (you would essentially be looking at something closely related to the step or impulse response of the resonant circuit).

The thoughts i refuse to view stuck in my head and cause a slight pain. And thank you for the interesting questions! If not disagreeable to you, I will reveal a bit more of my ignorance of deep understanding here. Take two aspirin and lie down. I feel like a robot who gets a feed of stranger kvalias that shouldn’t be feeden into my concious. Thank you for indulging me! NST: = neon sign transformer (?).If not disagreeable to you, I will reveal a bit more of my ignorance of deep understanding here.

Elmo’s Fire).Now, the fixed spark gap we consider for use with magnetically-coupled coils must obviously be set at a distance equal to, or less than, the maximum arc initiation distance. Originally Posted by deep’n’dark The thoughts i refuse to view stuck in my head and cause a slight pain. Once the full arc begins, how can it’s rate be anything other than 120 arcs per second (for 60 HZ)? No arc can be present as the voltage passes through the zero points of it’s waveform, and arc occurs somewhere before the sine curve reaches peak value in both directions, does it not? This assumes parasitics must be small, which is likely the case, as this type of transformer in service is essentially firing an “arc” through it’s load device (neon sign?) throughout it’s lifetime; some operate for years without failure.

Originally Posted by jocular Thank you for indulging me! NST: = neon sign transformer (?). What you would see is high-frequency ringing stimulated by each of those edges.

We know from experience that once the arc has struck, we can begin separating the terminals, and it’s length will increase, possibly to several times the initial “strike” distance, until it finally extinguishes. Given that the outut terminals of the transformer are spaced sufficiently apart to prevent arc initiation (they always are), a well-insulated probe (lucite-handled screwdriver) when slid in contact with one terminal and the tip brought gradually closer to the other, at some point of separation, a continuous arc will occur (call it arc initiation distance). Once the full arc begins, how can it’s rate be anything other than 120 arcs per second (for 60 HZ)? No arc can be present as the voltage passes through the zero points of it’s waveform, and arc occurs somewhere before the sine curve reaches peak value in both directions, does it not? This assumes parasitics must be small, which is likely the case, as this type of transformer in service is essentially firing an “arc” through it’s load device (neon sign?) throughout it’s lifetime; some operate for years without failure. By that time, I had already mastered the NST screwdriver trick, and made plenty of Jacob’s Ladders! Let’s assume our NST secondary has an open circuit voltage of 15KV, call that peak, so I can visualize the sine wave building up from zero amplitude towards it’s peak value. Just previous to this, a slight visual and audible effect may be seen, light-purplish glow, but not an actual ionization of the air allowing full current flow (like St. One would think that parasitic oscillations of any magnitude in the secondary coil structure would limit good life expectancy. jocular But the particular way it gets to zero (or away from zero) is an abrupt transition; it’s not a pure sinusoid.

Mucho long ago. Yes, on NST. One would think that parasitic oscillations of any magnitude in the secondary coil structure would limit good life expectancy. jocular The “arc extinction frequency” is indeed 120 per second, exactly as you say. What you would see is high-frequency ringing stimulated by each of those edges. However, due to the already ionized air surrounding the arc, it will not extinguish until the voltage waveform reaches that level where it is no longer high enough to maintain the arc. Related Discussions:Time machine within a time machinemy proxy is blockedYou & Your Username…Why is pain so bad?Migraine triggersExpanding universeWiki ShutdownTime Travel, all your ideas…..Time Travel, how you’d do it?End Program Surely, if secondary current is as near zero as it can get (only current flow is via incomplete ionization of the air surrounding the output electrodes), then the voltage is close to being a pure sine wave, is it not?As we gradually bring two terminals closer and closer together (the sliding screwdriver trick), at some separation distance a visible arc will signify near short-circuit current flow, but not quite.

This is typified by the Jacob’s Ladder experiment.Perhaps now I am beginning to see through my ignorance here: Because the secondary has very poor voltage regulation characteristics, once current begins to flow (the arc), the voltage does not continue on upward to 15KV, but rather “levels off” until time “catches up” with it’s beginning to drop back toward the zero-amplitude part of the waveform. Consequently, simple circuit simulations rarely reproduce accurately the waveforms you actually measure, but they at least capture the basics somewhat well.Your questions have me happily strolling down memory lane, so thanks a bunch for that! Fancy one’s lack of deep technical understanding being able to do that! Ha! Seriously, my “delving depth” of the theory involved here is limited to a course in “Pulse Circuits”, DeVry Technical Institute, 1963. If you are using a standard NST, there is a significant amount of leakage inductance and capacitance associated with its own secondary windings, so there is a definite resonant frequency associated with the NST itself.The spark gap does interesting things to the spectral content of the current. Since it sounds as if you are not using any tuning capacitors in the primary circuit of the Tesla coil, you’re relying on adjusting the spark gap spacing to hit the resonant frequency of your fixed secondary.

That can be made to work, after a fashion, but you’d get much more impressive results if you were to tune the primary explicitly, rather than relying on parasitic effects. However, there’s a bit more to it than that, and this is where the fun part comes from. If we look at the actual current waveform, we indeed see that it goes to zero (approximately) 120 times a second. If we look at the actual current waveform, we indeed see that it goes to zero (approximately) 120 times a second.

Elmo’s Fire).Now, the fixed spark gap we consider for use with magnetically-coupled coils must obviously be set at a distance equal to, or less than, the maximum arc initiation distance. Consequently, simple circuit simulations rarely reproduce accurately the waveforms you actually measure, but they at least capture the basics somewhat well.Your questions have me happily strolling down memory lane, so thanks a bunch for that! Just previous to this, a slight visual and audible effect may be seen, light-purplish glow, but not an actual ionization of the air allowing full current flow (like St. Hi, I am looking into the verticla pressure profile (with depth) of soils on other planets.I am interested in what the pressure in the soil is at shallow depths, where the soil at depth may still be in contact with air that diffuses in an out of the soil.

But the particular way it gets to zero (or away from zero) is an abrupt transition; it’s not a pure sinusoid. The same way that if you are in a cave the pressure is the atmosphereic pressure rather than pressure due to overburden of the rock above you.Does anyone know anything about what the ‘closure depth’ is in soils? ie. at what depth is the pressure in the soil due to overburden rather than atmospheric diffusion?Cheers Eriita Originally Posted by tk421 The “arc extinction frequency” is indeed 120 per second, exactly as you say. Given that the outut terminals of the transformer are spaced sufficiently apart to prevent arc initiation (they always are), a well-insulated probe (lucite-handled screwdriver) when slid in contact with one terminal and the tip brought gradually closer to the other, at some point of separation, a continuous arc will occur (call it arc initiation distance). At this shallow depths even though you are in the soil the pressure may be the atmospheric pressure, as the soil is not ‘closed off’ from the atmosphere.

In the absence of any resonant behavior, you’d see sharp — nearly discontinuous — transitions from “off” to “on.” Those fast-rising/falling edges are a signature of very high frequency content.If there are resonances, those sharp edges will excite them (you would essentially be looking at something closely related to the step or impulse response of the resonant circuit). It’s like my input kvalias or the stranger ones, are there and when blocked, they cause pressure.

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