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ArcticMyst Security by Avery

Homemade CO2 laser power supply






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Mar 7, 2011
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Have you considered a good old fashioned neon sign transformer being fed A/C by a variac, from the neon sign transformer output go into a voltage doubler of HV diodes and caps. A 15kv 30ma transformer into a voltage doubler would net you up to 30kv @ ~ 15ma.

Just an idea.
 
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Feb 1, 2008
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18mA at 20kV is 360 Watts, that's quite a lot of power. Consider that the max beam current in a CRT display is typically 1-2mA and consumer goods are rarely made with much of a margin. Some flybacks are more robust than others but I have burned out several of them. Some suffered insulation breakdown from pushing them too hard, others overheated and burned out in plasma speaker experiments and Jacobs ladders. I've only ever cut open one flyback and the wire was about the smallest I've ever seen, it looks like a strand of hair.

I regularly pump ~500W into my flyback without a problem while using the ZVS.

Use a smaller inductor for more current and less voltage, and use a larger inductor for less current and more voltage.
 
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Feb 28, 2011
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How much was the total price to build it all?
For the power supply, about 20-£30 (~$50), but i did have most of the parts kicking about the place anyway, such as the transformer.

Have you considered a good old fashioned neon sign transformer being fed A/C by a variac, from the neon sign transformer output go into a voltage doubler of HV diodes and caps. A 15kv 30ma transformer into a voltage doubler would net you up to 30kv @ ~ 15ma.
I've seen neon sign transformers used to power these types of lasers many times before. Getting hold of a decent NST proved fairly hard for me, that and i wanted somthing i could power from batteries if needed :evil:

Use a smaller inductor for more current and less voltage, and use a larger inductor for less current and more voltage.
Yeah, I went through pretty much every inductor i could find and wound several of my own before i got just the right output...
 
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Oct 28, 2007
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Correct me if I am wrong but if you're going to hook up an NST to your CO2 laser make sure you achieve full wave rectification first

Regards,

amk
 
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Feb 28, 2011
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amkdeath said:
Correct me if I am wrong but if you're going to hook up an NST to your CO2 laser make sure you achieve full wave rectification first

Yep, thats right. You could probably get away with half-wave and a capacitor, but full-wave with a capacitor would be the best to avoid the laser pulsing on and off 50 or 25 times a second. (depending on which country you live in)
 
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Jun 24, 2010
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The laser tube won't mind half wave rectification, but it will cause a DC current in the transformer core and risks saturation. Transformers don't like this and will run very hot. As with most things, your mileage may vary, but HV diodes aren't terribly expensive. Last I checked All Electronics had 6kV rectifier diodes for around 50 cents each. Build a bridge out of four strings of 3-4 of those in series and you can rectify any ordinary 50/60Hz NST.
 
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:beer:
Can't help but spread a little rep to Pieznice29 & james1095. :san:
 

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I've run my CO2 from a NST fine, however it's not recommended to run them from AC as the direct current is used to push the gas around the tube, and out into the catalyst tube where it can recombine into CO2. Without this push, the CO2 in the bore will split up and it'll probably stop lasing.
 
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It won't stop, the power will just drop. They have extraordinary gain. Mine still lases at 2mA
The laser tube won't mind half wave rectification, but it will cause a DC current in the transformer core and risks saturation. Transformers don't like this and will run very hot.

From what I've read, NSTs take the abuse better than most. "these transformers are designed to run for years in near short circuit conditions"
 
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May 30, 2014
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Stunning work I want to know what the circuit diagram you work on it please reply quickly
 
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Feb 18, 2013
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Stunning work I want to know what the circuit diagram you work on it please reply quickly

Umm, this thread is almost 3 years old. I highly doubt they will get back to quickly.
You should post in the welcome thread, and next time look at the date of the posts.
Some people will get you for necroposting...
 




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