Tesla Coil Build Thread

[Grix]

Yay, ordered a onetesla a few days ago and now it has shipped!

 

[Speedy78]

Measure the resistance of your secondary. If its around 220 use a five turn primary. Or do as I did and redesign the primary.

 

[Sigurthr]

Nice, Grix! If you run into problems you know where to post for help =).

Let us know how the Tesla Partying goes, fellas!

 

[Fiddy]

It went swell! many people where amazed of its awesomeness

 

[DashApple]

Well my 220 mosfet bridge died xD , made it to 200 volts on the variac .

So I remade the full bridge with TO-247 mosfets and it made it to the full 250 Volt AC supply , Primary is 10 turns . The bridge is 1000uF smoothed with another 2.8uF PP cap as a snubber on the supply . then there are 2 10uF snubber capacitors on each leg of the full bridge .

( looks a lot better in person ) Pic is full supply , fully CW running .


IMG_0168[1] 279 by TwirlyWhirly555, on Flickr

 

[Fiddy]

Wow nice CW discharges their ion!

Made a platform for my pancake coil today! Should look good with the clear base underneath.

 

[Speedy78]

Where are yoy getting your acrylic from? Also whats holding the couls from unwinding or are you goung to glue it?

 

[Fiddy]

I bought this black 4.5mm A3 sheet a while ago off ebay, yeah gunna hot glue it cause hot glue comes off easy if i need to readjust the turns

 

[Speedy78]

Need to invest in some thick squares for my top and bottom sections of my chaddid and then some for my conical coil. Problem is I want rounded corners. May need to hit up Things again for some cut acrylic!

 

[Sigurthr]

Looks great!

After a few hours of hell I got my Digispark based MCU Interrupter working. It's good enough for a basic SSTC, and good enough for a basic level option to share with others, but I won't be fully endorsing it. The usb interfacing leaves a LOT to be desired. It isn't fully usb compliant, the connection is buggy as hell, and it is a nightmare to get a pc to recognize it. At least my code works fine.

The good news is that the ATTiny85 itself works exactly as expected, aside from the internal clock being about 20% slow. The main problem is just the digispark as a platform. It looks like I'm going to have to get an Arduino UNO/DUE when I can afford to and just make an ATTiny85 ISP Programmer Shield for future ATTiny projects. I'm glad I only spent $20 on the digispark + protoboard shield + breakout shield + shipping. I'm glad I did get those two shields as well, the proto one will be used for all the connections for my actual interrupter, and the breakout shield made it a LOT easier to do debugging and testing.

I think I'll use a full blown UNO/DUE for my 1MHz DRSSTC interrupter though. I can't afford to be blowing bridges because the internal clock on the ATTiny is 20% out.

It just sucks because at $8 for a $2MCU + $2VREG + built in dev board + basic breakout was an awesome deal. I guess the arduino based ISP saves money in the long run, but it is a lot harder pill to swallow.

 

[The Lightning Stalker]

I was using the Arduino ISP the other day to program, guess what? An Attiny85! :wtf:

It does work very well once I figured out to power the target chip and all of the gotchas to disable the
auto reset.

I due recommend the UNO simply because it is one of the better supported newer ones. The others
tend to have their own idiotsyncracies. The only reason to go up to the higher boards such as the DUE
would be if you seriously need the computing horsepower or more I/O pins. I would also avoid the
Leonardo, at least right now because the single chip USB can complicate things and cause
incompatibility with shield boards, etc. The UNO is the most compatible and you can pick it up at
almost any local Radio Shack.

 

[Fiddy]

gave it a test run with the pancake coil and tuned it a bit, here's some results, its resonating at ~520kHz.

 

[Sigurthr]

Sweet. Is that running off your lil trafo, Fiddy?

 

[Fiddy]

Yeah my 180VA Beast! Would putting a 10uF power factor correction capacitor on the primary of my tranny do it some good?

 

[Sigurthr]

Doesn't hurt, prob won't see any secondary side performance improvement though. It looks like your tank cap is too small, judging by the output.

 

[Fiddy]

what output would you expect for 500kHz and 180VA?