TEA Laser Build

Hello all, I wanted to share my TEA laser build so far.

After doing a lot of reading I think I have the build just about correct.
Here are some of the pages I used for ideas.

http://www.sparkbangbuzz.com/tealaser/tealaser7.htm

http://192.197.62.35/staff/mcsele/lasers/LasersTEA.htm

Here are some photo's of my build....anyone that has done this before is more than welcome to input anything they see will help.
Also I got my neon sign transformer today in the mail and NEED HELP hooking it up. I have a VERY healthy respect and fear for high voltage(coming from an experience when I was a kid)
Frankly I'm scared to death of the thing and want some input on how to wire it up for use and what to look for so I don't get thrown against a wall(again:undecided

First showing the thin copper base, then dialectic(overhead sheet), then the tin foil top.
[/IMG]

[/IMG]

The mostly completed unit, ready for the NST to be hooked up.
[/IMG]

[/IMG]

Now for the NST....This is a France NST 7.5kV, 30mA with an on/off switch. No GFI
[/IMG]

[/IMG]

[/IMG]

There is a white wire and black wire....from what I understand one is positive, one negative and i'll have to add the ground wire to the chassy......This should be where I wire up for the plug that goes to the wall?
[/IMG]

Here there are two holes, I might think for the connections coming off the NST? Here is where i'm really not sure what to do. Is there a positive and negative side to this? The NST did come with some extra HV wire but in many photo's of the TEA laser it really doesn't show the power supply set-up that closely.
[/IMG]

Thanks for looking and hopefully someone can elate some of my fears of that NST and let me know how to SAFELY hook it up and use it.

I don't have a Variac, it's next on my to buy list....and i'm hoping that for now I can just directly hook up the NST...if even just for a bit to see if I got it all correct.

It's AC - there is no +/-. If you're familiar with residential 120 and 240V, this is similar. Each of the poles will be 15kV with respect to ground, but you will see 30kV on one pole with respect to the other.

As far as safety, don't touch anything while it is energized, and short all capacitors before working them.

Cyparagon said:

It's AC - there is no +/-. If you're familiar with residential 120 and 240V, this is similar. Each of the poles will be 15kV with respect to ground, but you will see 30kV on one pole with respect to the other.

As far as safety, don't touch anything while it is energized, and short all capacitors before working them.

Click to expand...

Thanks for the input. So am I to understand that I wire both of the poles up and hook both sides up to the TEA laser? Or One side from the NST to the TEA and another wire from the TEA to a ground?
Sorry for the questions, but this is really where i'm lacking information. I'v looked for how the wiring should go but not found enough to progress.

As for shorting my capacitors, in this case I think that the plates of the laser itself is the capacitor?:thanks:

The plates of the laser are the capacitors. Normal household voltage has a phase and zero connection (at least here it's that way), neon sign transformers have two phases (in opposite phase) and the zero is probably internally connected. You'll probably need to rectifiy the voltage with some HV diodes to get DC with both + and - far from ground potential. Running your laser at 100/120Hz won't be very efficient if it would work at all.

Thanks Bluefan....I'm almost there, may still need to pick up a couple of parts though.

Perhaps you could be more clear on How to hook it up. This is the only part that is not very clear in the different instructions I have read. In the pictures you see I have two connections there inside the NST. Do I connect a wire to both sides and then both wires to the laser? I think I have 'where' the wires go but not sure if one is just a simple ground wire not coming from the NST or both wires are coming from the NST.
Also i have read about the HV diodes in line with the NST, but not sure what kind...12kV HV diode?
Thanks yall for the end help, I try to do all the reading and put these things together myself, I just don't know enough about the HV yet though....did a whole bunch more reading last night, but not there yet.

Okay then.....wired up the NST, pluged it in, hooked up both sides to the TEA.....unfortunately had an arch from the bottom layer through the dialectic and to the top layer....I guess I'm in for a bit of rebuild.:tinfoil:

On the positive note...the NST does seem to work.........and i'm still alive!


EDIT: Keepin' up the work......Welp as said I need to get some HV diodes, just need to figure out what value they need to be....
What i'v been running into without the diodes, for those who might be interested, is hot spots that burn through the dialectic. Lucky that these are pretty easy to re-build.
This is a lot of fun, and now that I know how not to get killed by my NST its a bit easier to work with.....still VERY hesitant with the thing though, there's just nothing like being thrown across the room by electricity.

Bluefan said:

The plates of the laser are the capacitors. Normal household voltage has a phase and zero connection (at least here it's that way), neon sign transformers have two phases (in opposite phase) and the zero is probably internally connected. You'll probably need to rectifiy the voltage with some HV diodes to get DC with both + and - far from ground potential. Running your laser at 100/120Hz won't be very efficient if it would work at all.

Click to expand...

Still trying to figure out everything that you said....learning about phases of electricity.....Thanks for your help.

On a side note....Pretty neat web site you have building up there. Some interesting reading. Your Coherent DPY 315M is very interesting, even though quite a bit beyond my electronics understanding.(i'm getting there though)

yours is much neater than mine turned out. Mine used those L-channels too, had bigger capacitor, though. it was all thrown together without much care, but I still managed to coerce some UV photons to march together ;-)

I have no doubt that yours will be much more successful and I can't wait to see it lasing!

I'm working on it, I have to order some HV diodes and would love to get a variac as well just to make things easier.....perhaps down the road making a real for real Nitrogen Laser.


I'll get this one to lase first though.....

My first try wasn't very succesful, I have a -20kV 300uA power supply, but somewhere around 8kV it stopped and probably shorted somewhere, but I ahve no idea why. All I got was sparks acros the electrodes instead of an even discharge and I abandoned the project, I'll pick it up later. It isn't even on my website, I'm currently expanding/improving it, the newer projects aren't on there yet.

Welp I must say I am VERY excited!

I got my homebuilt TEA laser to work!!!!

At first I was running it directly off the NST without any resistors. I kept burning up my dialectic, perhaps because of design flaws or more likely because I was missing that resistor.
I ordered two kinds.....(this is very unscientific for me...really don't know what i'm doing). 2 30mA 30kV diodes and
10 10mA 12kV diode.....
I didn't know which I may need for my NST or even if they would do the job. I put in the order, from what I though was going to be a state side shipping, ONE MONTH LATER...shipped from China, it showed up today.

I just couldn't wait to give it a try again. I decided to try the higher voltage one first...who knows, seems better.....30mA 30kV diode. Soldered it on, hooked up the NST and fired it up...fully expecting to destroy one of my few dialectics left.

But to my surprise....IT LASED on the first try. I just got lucky with the alignment for the spark gap and rails I guess.
This this is just as loud as the videos i'v seen!

This is my first video post ever, so sorry if it's not what you are used to...i'll try to make it nice.

That looks awesome what does it look like in person? Is it really that blue?

midias said:

That looks awesome what does it look like in person? Is it really that blue?

Click to expand...

It is awesome!....thank you, i'm kind of proud of myself for getting this to actually work.

You shine it on the white printer paper because, from my understanding, there is a small amount of Fluorescence made into the paper that allow the UV to show up. So it does look pretty blue on the paper.

Another Run video....of it working okay.
At one time one of the leads burned through my anti-static mat, so I put it on the plexi. Also it seems like the diode is starting to fry...starts smoking and I turn it off...if anyone has a fix for this I would appreciate it.(perhaps if I put a few diodes in a row?)

Anyways...another video for those who might be interested....I'm still excited that it works!

That is very nice alignment! Mine was discharging more towards one end of the cavity, but it still managed to put a dot downrange.

Nicely done! I'm glad you figured out why it kept frying itself :eg:

Thanks much....I read that the best gap is 1mm. I used a paper clip to get the distance set...same with the spark gap(although that is more like 1.5mm) and to my SURPRISE it all fired up!
I cooked another dialectic messing around with it a few days ago, so I have to put it back together, but that's the great thing about these TEA lasers in how easy they are to make and remake when you make a mistake or two or three or four.....=)