The Jacobs Ladder thread

[Tech_Junkie]

A question I cant find answered directly anywhere (I even emailed pros) is, can you use a GFI enabled NST? People say no in most places, but I've also read that as long as the arc does not hit the case of the NST there is no issues. The GFI units are half the price of non-GFI units. If they can, can they be phased? At half the price I can get 2. :eg:

 

[Markus Unread]

Spark gaps (like ladders) are broadband RF emitters with much of the low frequency being conducted into the power line. If you create a ladder with an old style neon or oil-burner ignition transformer, the hunk o iron limits the HF conducted. Find a Corcom filter, ground it well, and hook it up with the "input" facing the transformer.

Radiated emissions - drop off quickly with distance. You could ground the laser module case, or shield the whole thing (power supply and all). Jacob's ladders aren't Tesla coils so the shielding isn't nearly as necessary. You could also use mirrors to remote the laser.

Most importantly, Jacob's Ladders create lots of ozone and electrode-oxide aerosols when running so vent well.

 

[00Giorge]

Since when does glass shield against EMI?

No idea I was just repeating what the old professor told me, he said that if I ran it where my stereo system was that the J ladder would kill it. But if it was encased in glass that it whould help protect it. That was in 1983, he could have been full of it as far as I know. I haven't found anything that supports what he said.

I think he was smoking something, he had 18 kids! :beer:

 

[dnar]

Nice work. How far was the laser away from the ladder? I'd like to put one right under bottom of the ladder, between the rails where the arc starts. But I've heard electronics and ladders dont mix. I wonder if the laser would survive that close. :thinking:

The 532 laser was 3 feet away. Both laser and ladder where on the floor under my bench (darker). The laser was beaming up at approx 45 degrees. Cameras loose all perspective.

This is as close as I dare... These things are evil, the broadband EMI is insane.

When it was running, my son complained his PC speakers where going nuts (15 meters away) and the wife complained the TV reception was shit.

The neighbours have no idea I am to blame...

BTW, when I first built this (years ago) I had it on the bench, with the lab supply behind it. I reached around to dial up the juice and my arm came in to contact with the ladder. Oh man, it belts like a bitch!

Last night I made two new electrodes for it, using flat ali bar. The trick is to keep the two electrodes as straight as possible, to assist the arc moving all the way up. It now performs really well. Video later, when I return from the office....

H_T, check this out http://spk.if.uj.edu.pl/ConsciousFlesh/jlad/JLAD_eng.htm

 

[Tech_Junkie]

I like it. Tony told me I could run the flyback ZVS driver off of 2 portable drill batteries.

My vision is a 6 foot ladder with 10 inch arcs flaring off it. I might have to dial it down some.

 

[dnar]

I like it. Tony told me I could run the flyback ZVS driver off of 2 portable drill batteries.

My vision is a 6 foot ladder with 10 inch arcs flaring off it. I might have to dial it down some.

A 6 foot ladder? Holy &*#^&%@

You mean like this?

http://tesladownunder.com/

This guy lives near me, I have spoken to him before, his is full on! He is a doctor believe it or not... He built a tesla coil for our science discovery center, talk about loud!

 

[Tech_Junkie]

I did say Frankenstein lab size, LOL. I did read his site about a year ago, and was very impressed. I'm just like him, all or nothing. I wish I lived near him. *Jealousy*

 

[Markus Unread]

Portable Jacob's Ladder

I love the whole TeslaPunk look of that thing. Nice!

PS- Check this place out...

http://www.darkroastedblend.com/2007/07/creepy-high-voltage-installations.html

 

[Tech_Junkie]

To bad there is only one picture.

I'd love to see some video too.

 

[Markus Unread]

They should open it up as a tourist attraction. It's right outside Moscow.

 

[Tech_Junkie]

Stupid question, but what is the round red coiled thing? I have a few of these, and never knew what they were for. HV I assume.

 

[DashApple]

Tech_Junkie , Yeah the arc are quit big in my setup

The red thing is a inductor i belive , using a powderd iron core , best type of core to use inductor goes on the input side of the ZVS , they are quite improtant . carnt quite remeber what they do , someting to do with power control .

 

[Pilgor]

isn't the red thing just a ferrite toroidal transformer?

 

[HIMNL9]

It's a toroidal coil (or transformer, if it have more than one wire )

It can be used in the circuits, as a coil placed on the power supply line, in two ways ..... first, it block almost all the high frequency disturbs that can flow back from the oscillator to the power line ..... second, it can act as "energy storage" for the oscillator (a big capacitor is not the only way for store energy, when we're speaking about high frequencies ), so it don't take too high "current spikes" from the power supply when it close the circuit on the primary of the HV transformer .....

Toroidal coils and transformers are a bit more difficult to wire than linear ones, but are more efficent and compact than linear coils, and also emits much less electromagnetic disturbs around, being "closed magnetic circuits", so are preferred for small spaces and high frequency assemblies.

 

[Addonex]

No idea I was just repeating what the old professor told me, he said that if I ran it where my stereo system was that the J ladder would kill it. But if it was encased in glass that it whould help protect it. That was in 1983, he could have been full of it as far as I know. I haven't found anything that supports what he said.

I think he was smoking something, he had 18 kids! :beer:

If anyone here has been to the Fry's Electronics in San Marcos CA. you'll probably have seen the 4 massive ladders they have there. 2 outside and 2 inside both encased in glass (I assume this may support what your professor was saying). Two of these slightly smaller monsters were located right inside the store with many displays/electronics within feet of towers.

I took this picture during a visit a while back of the two outer ones, those 2 blue towers on either side of the entrance:

Take a look at the people/cars/door to get an idea of how massive these things are, the arcs inside were easily 2 feet across near the top. Quite a sight to behold :bowdown: Hopefully I'll get some video of them next time they turn them on while I'm there.

 

[Toke]

Some welding machines have a coil in the output to limit current.
It looks a bit odd to see it sitting inside between the transformer and the handle terminal, rather unmotivated until one realise the purpose.
The idea is to have a high starting voltage to strike the spark, and then have it drop one the arch is going.
The current limiting function is similar to the ballast in a fluorescent tube.

So inductors/coils can have many different purposes.