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ArcticMyst Security by Avery

Tesla Coil Build Thread

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That'l work fine. You should eventually upgrade to a 4-cord setup as I suggested earlier if you're going to stick with 25' lead-length as it will give a boost in performance, but you don't have to rush into that now.
 





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I have an old 24th dryer cord I may be able to wire into a standard plug. It's only like 3 feet and is high Guage. Will just have to set the coil right next to the lawn.
 
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I've got about 25ft of 10/3 RF ground lead-length for my dedicated line but it is impossible for me to shorten it any, so it is certainly doable with a 10/3. I also have it paralleled with my RF-pass/equalization mains network too though, and that's what makes it a bit more effective than a standalone 10/3 25footer.

In short, don't worry about it too much. Using mains plus makes it really easy to parallel more cables in the future as needed, all you need are standard splitters and extension cords.

You will see an increase by increasing the gauge of the primary side wires though for sure, and it is noticeable, but don't worry about that until you have a solid ground solution. Ohh, and be sure to round off the ends of your strike rail.
 
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Ok first light went off with out any damage but really nothing as far as output. Without a breakout there is little to no output what so ever. There is a lot of purple between the toroid and strike rail. When drawing arcs I can get about a foot before they break. Checked tuning as my secondary is sitting way down just over 100Khz. No where near enough turns to get there. I was originally set on a lower turn count, when going to more turns the output disappeared all together. Maybe my joint where my three separate sections of copper tubing meet cant carry the current? Will beef those up when I have the time.

My ideas to fix this:

-New secondary with less turns to get my frequency up near 200Khz
-Thinner secondary to get my toroid further from the strike rail

Any other ideas?

Will be upgrading to bigger primary hook up wires latter. Just wanted to get a light while the parents were in town. I cant imagine this was causal in the extreme lack of output.

This run was the first with a 170/106 split on the two coils. Tapped more turns and got around 163 but all output stopper?
 

Fiddy

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can you remove primary capacitance easily?

Only other way is to remove topload capacitance via changing the toroid, try your onetesla toroid?
 
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Too bad you couldn't have gotten in closer with the camera. Haha at "it's so loud!" at then end. I warned ya.

So you said you were at a 170/106 split, which coil was which? I assume the secondary was the 106. This means that you were driving the secondary at nearly twice the frequency, which would be why you were getting some breakout and why it decreased when you got to 163 as you moved farther away from the 2x harmonic (212).

If you can't tap at any more turns you have a few options:
1) increase primary capacitance.
2) decrease secondary capacitance.
3) remove secondary turns.

#2 or #3 is the easiest and probably best one to go for as it won't mess with the impedance matching of the transformer to the MMC.

Unlike with a DRSSTC tuning far off resonance won't blow up your rig, don't be afraid to try all the tap points.
 
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I tapped at the furthest turn and there was no output whatsoever. Removing turns will work but currentlyhave a lot of corona going from the toroid to the strike rail . Almost like a skirt around the whole thing. Is my top load to close to it? If so I may make a smaller diameter secondary with less turns to put my toroid up higher.
 

Fiddy

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have you tried removing the strike rail if its easy to do? how is your coupling?
 
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For sure what you're describing sounds like the secondary capacitance is at issue.
I'd go tap the coil at it's sweet spot and then change the top load to something half it's size
and see if that doesn't make a difference.

I think a lower capacitance toroid will be the key here.

Good try!!
 
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It's a 12 30. My frequencies are too far off at the moment to really test anything else.

Edit: I like this toroid and want to stay with it that's why I'm thinking of rewinding the secondary to get this to line up.
 
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It's a 12 30. My frequencies are too far off at the moment to really test anything else.

For that small a transformer supply I'd be inclined to use a popcan sized toriod. Actually, that might work quite well.


:beer:



If you are able to, upgrade the suppy to 120mA
 
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I can't seem to find any transformers in the area. All are 30. I should at least get decent streamers once I get this running right. I'm not looking for them to dance around on the ground or anything but at least some bright ones running around the toroid
 
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Up to you which route you want to take. Was the corona between the topload and strike rail focused in any area or just diffuse? It may be a bit close, generally you want the strike rail about 1/2" to 1" above the top primary turn. Even though it is a power loss, it generally won't cause massive tuning issues (it does drop the secondary frequency some).

I doubt coupling issues are at play here, you would have seen racing arcs.

The spark gap sounded a little funky, but it was too short to tell for sure.

If you want to make a new secondary you should aim for the frequency to be between 1/2 and 3/4 of the primary tap range, that way you can adjust it well. It is hard to increase height/length while reducing turns, the best way is to use a smaller diameter form and use a thicker gauge of wire. Maybe grab some 24ga?

So if the lowest your primary circuit can go is 163 aim for 200KHz for the secondary.

EDIT: BEFORE YOU REMAKE ANYTHING GRAB A SMALLER TOPLOAD AND HAVE A GO. SEE WHAT YOU CAN GET.
 
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Yeah I was planning on a quarter inch smaller and thicker wire. It was focused. It was almost like a purple skirt from the toroid to strike rail. No visible streamers and not focused on anything. Only other top load I have is the one tesla. Is that too small? I have one out of dryer ducting I made a while ago that's bigger than the one tesla but smaller than this one.
 
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If a topload gets it in tune it cannot be too large or small, just not ideal. But you need a tuned working coil to proceed to refinement stage.
 




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