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Tesla Oscillator

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Tesla C

Wed Jun 18 2008, 06:27PM

Registered Member #1551 Joined: Wed Jun 18 2008, 06:21PM
Location:
Posts: 7

Okay so has anyone ever built a tesla oscillator? I have looked for plans on building it but could not find anything, anyone know?

Thanks

Experimentonomen

Wed Jun 18 2008, 07:51PM

Registered Member #941 Joined: Sun Aug 05 2007, 10:09AM
Location: in a swedish junk pile
Posts: 497

The mythbuters tried but failed, apparently tesla used a pneumatic/engine driven jackhammer, however the mythbusters ended up using a linear electric servo motor, with a weight attached to it to get any effect at all, and still it wasent even close to teslaÂ´s claim of almost bringing a building down.

Coronafix

Wed Jun 18 2008, 11:08PM

Registered Member #160 Joined: Mon Feb 13 2006, 02:07AM
Location: Melbourne, Australia
Posts: 938

The fact that Mythbusters failed isn't really saying much.
Tesla's mechanical oscillator I believe was based on his patent for his reciprocating engine.
It would not be enough though to simply build it then set about bringing down buildings.
You would need to know the frequency with which to vibrate the building at.
Because with resonance, the effect is not immediately seen, it needs to build up over several cycles.
I think that Tesla would have done his math before attempting his building vibration trick.
As with a swing, even a small push can be built into a big swing given the timing and position of the
next push.

Tesla C

Thu Jun 19 2008, 01:35AM

Registered Member #1551 Joined: Wed Jun 18 2008, 06:21PM
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Posts: 7

Well I never thought of actually taking down a building with it. I just got a few ideas now at how to start. Any more help is welcome.

Bjørn

Thu Jun 19 2008, 02:12AM

Registered Member #27 Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058

Ignore Tesla and Mythbusters. Read about mechanical resonance and damping, that should get you on the right track.

Hon1nbo

Thu Jun 19 2008, 02:13AM

Registered Member #902 Joined: Sun Jul 15 2007, 08:17PM
Location: North Texas
Posts: 1040

also in the mythbuster's tests, they tried it on structures that are designed to have the least likely chance of having a destructive harmonic frequency within that which the mythbusters could have made with that thing... and their "small scale test" of Tesla's building was not good at all, as the steel skeleton design of buildings was not around at that time... the walls bear the load then

Fraggle

Fri Jun 20 2008, 12:40AM

Registered Member #1526 Joined: Mon Jun 09 2008, 12:56AM
Location: UK
Posts: 216

It`s clearly possible to make things, even buildings, resonate. The only question is; how to get a sufficiently large mass oscillating with enough amplitude to do anything interesting AND allow the frequency to be adjusted?

Steve Ward

Fri Jun 20 2008, 04:40AM

Registered Member #146 Joined: Sun Feb 12 2006, 04:21AM
Location: Austin Tx
Posts: 1055

Dont forget that resonant objects have a Q, and for most things its pretty low, meaning you will never store more than a few times as much energy in the resonant object than you store in your driver.

I personally dont believe it would work on any decent structure, unless of course your driver was a good fraction of the size of the building.

Marko

Fri Jun 20 2008, 12:59PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

BjÃ¸rn BÃ¦verfjord wrote ...

Ignore Tesla and Mythbusters. Read about mechanical resonance and damping, that should get you on the right track.

Yes, Mythbusters had some grave misunderstandings - like measuring the fundamental resonant frequency of a steel bar hanging in air (which was actually in kHz and had nothing to do with resonant frequency of structures it may be used in), then trying to *break* it by a small vibrator operating at no more than few tens of Hz??, or, waiting for hours for resonance to ''build up'' on a very low Q system, where it actually does in first few cycles, and etc.

They are not to be considered as scientific evidence but I'm sure they would be happy to revisit and correct their mistakes if someone guides them into it.

About the whole earthquake machine thing I only know anecdotal tales and not really much concrete evidence about anything. I can't really comment on whether Tesla has done it or not, but someone can investigate basic possibility of the very thing;

Mythbusters have for example set the goal as 'could Tesla have created a small machine which would produce an earthquake-like effect in a building'.

Power input, type of building and even the size of the machine seem completely undefined though, which makes any concrete investigation hard.
Mass of the machine is not defined either, and a large reciprocating mass may be beneficial in some cases.

If I had to 'bust or prove a myth', there are many things that could be done.

- Define what is to be called an ''earthquake effect'', or whatever - some threshold of vibration amplitude must be stated.

- there's no obvious limit in power supply nor type of power input. Having a huge boiler providing a few tens of kW worth of steam is obvious advantage, and it's not a part of machine. But even that may not be needed. Size of device doesn't really matter alone, it's the *power input* and *Q* that matter.

- No information on the duration of effect or necessity of permanent destruction to prove ''earthquake effect''. So probably a tank of compressed air may be just enough to provide high peak power for short time.

-Finally the type of building I would want to use is one with weak damping, high rise construction of probably some old design. Heavily damped structures like truss bridges are apparently poor choices.

Mates

Fri Jun 20 2008, 04:12PM

Registered Member #1025 Joined: Sun Sept 23 2007, 07:53PM
Location: Czech Rep.
Posts: 566

I saw a damaged building by turning-lathe which got out of control at so called critical rotation speed. Massive piece of concrete was pulled out from the floor (the turning-lathe platform) and there were raptures in the concrete spreading meters away. Guys working there that day said the whole building was shaking... So, I think it is possible to make earthquake effect by some kind of vibrator, but I doubt it could be in the range of pocket size...

Another experience I have with a large subwoofer (400W, 50cm diameter membrane) fixed inside a metal barrel hooked to signal generator. By gentle tuning at high power in low freq. you can shake with different things in the room. It is a lot of fun and cool way to study the higher harmonicsâ€¦

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