oneTesla

Well after relearning how to read and a blown IC I seem to be up and running. Having never had anything like this before I cant say if its operating to its full potential or not but it seems to be. Still working on borrowing a scope to see how well in tune it is. This is at about 50% power. Some nice sparks! Had a pumpkin with a fluorescent bulb in it but the streamers seemed to like the pumpkin more and would cause it to latch up so I had to shut it down. So this is just the coil by itself doing what it does best.

http://www.youtube.com/watch?v=4Bf9nwDs ... e=youtu.be

So those of you with tuned coils is this a typical output for 50%.

Edit: Another video for your enjoyment.
http://www.youtube.com/watch?v=WpCNUaecWSw

And a couple pictures.

Well done - nice looking case!

Nice carry case you have there. I want to find one for mine but they aren't cheap over here. Only thing I'd be concerned about is when carrying it by the handle. That would put the heatsink so that it was pushing against the IGBT's in such a way that it can be susceptible to transport damage. Not sure if it would be significant over time though, but I can imagine that if it were in a car on a bumpy road, that may not be ideal.

Can't quite comment on if your coil is running ideal for 50% power. There are quite a few variables to consider as well. All I can really say is that this is mine running Tetris at 50% power: https://www.youtube.com/watch?v=qzuiuku-cps&hd=1

I have a few videos up of recent runs at 50% power if you want some comparison, however I believe my coil is still out of tune. By how much.... I don't quite know. Well I do know how much... Just not how far from ideal.

Yeah im thinking about taking a rubber band and running it around the heatsink and the two caps that are secured better to the board. Will pull the sink to touch the board and should alleviate any stress to a certain degree.

Yours seems to outperform mine by a good bit at 50% but its hard to tell with that camera angle and me usually viewing mine head on. I have a guy offering me his Leader dual trace 20mhz to test it. Not sure if that scope will work or not. He says its quite old. I also know nothing about them.

Yeah, I had previously taken lots of videos with a front on view so thought I'd mix it up. Don't have much yet on the recent runs, but here is Axel Foley front on: https://www.youtube.com/watch?v=9ildK5i0UhY&hd=1

I have a bunch of older videos there as well if you look on my channel. There are some mid-power runs from a while back when I was experimenting with tuning. I do have a sequence of photos from mid-power fixed frequency testing too if you click on my link in ny signature and look at the most recent posts. Once again, mine most likely isn't the best point of reference but once you find out your resonant frequencies, it would be good to have some comparative data.

Yours is definitely giving out larger sparks than mine did when I first built it so at least your level of tune isn't going to break anything at those power levels. Just best to not exceed mid-power until you get that scope to check things out. If you have some time, I'd recommend building that 555 based Tesla coil tuner so you have a slightly more accurate way of finding out how tuned your coil is.

http://www.rmcybernetics.com/projects/D ... _tuner.htm

Thst thing should be easy to build though im not sure if I would be able to calibrate. Ill see where its at before I build this though. Anyone know a good but cheap usb type scope I could purchase later on? I can see myself building some.more coils in the future

That old Leader scope you were offered should outperform (and outlast) most low cost USB devices, but a USB scope may be more convenient. Almost any scope should do the job. Tesla coils operate at frequencies that are just 10x higher than audio frequencies, like 200-300 kHz, and no scope I have seen has had any problems giving good results in that range.

Your spark looks about right for a reasonably well tuned coil at 50% power. Can't really say for sure, though, because my oneTesla is operating at 300/330 kHz with a 5 turn primary, and that seems to make a stronger than usual spark at 50% power.

I have a new primary! Although my 5 turn primary ran fine I decided to make my own. First I tried to replicate the vertical coil with thick copper ground wire. It ended up being way to difficult work with in such a small environment and the turns kept overlapping. When I ran It any higher than 25% it would arc from the primary to the secondary. No good.

Next I tried thinner copper wire. About the same thickness of the coated wire in the kit. This was much easier to work with but still didn't work properly. Anything higher than 40% it would arc to the primary from the secondary. I added a piece of PVC to block the free air gap and added a strike ring. This got me to about 50% before a arc from the secondary carved a groove through the PVC and hit the primary.

I decided to stop trying to wing it and run some number in javaTC. Found out real quick that I had a huge coupling issue with the thicker wire. Still wanting to use the thick stuff to help dissipate the heat I diced to build from scratch a horizontal coil using the same wire.

Started off cutting out a huge circle of plexi to support the now flat coil.


Next up I made these plexi glass spacers and glue them to the new primary former. (old one is still 5 turns of stock wire in case I need to swap primary for whatever reason) This is actually upside down.


Wrapped tap around the outside to help brace things as I began to lay down the primary.


Flipped it upside down and glued it to the large circle I made earlier. Now there is no way from the primary to pop out of the notches.




This was coated wire that I stripped off. Left the lead in wire that is overlapping the turns still coated, all the way down to the bridge.


New strike ring just in case.


Copper looking secondary, copper primary




Strike ring plugs into a plug wired directly to ground.


Here is the other side of the bridge. Just a little alligator clip with a bent nose.


Here is a run at min power.




Here is a half power run.




And the money shot!

Had some fun messing around with the streamers tonight. Enjoy.

http://www.youtube.com/watch?v=JrUzhgXU ... r_embedded