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ArcticMyst Security by Avery

TEA Co2 laser build

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Nov 12, 2010
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well i plan to build a tea co2 laser with the intent on creating an ionized air pathway to run high voltage through

any suggestions

currently i have built a cap bank made out of 300 photo-flash capacitors
its about 5KJ and 800v but can be modified to 1600v if needed

im aware that the inductance may be to high even with pre-ionization via UV spark gap

basically i would love some input on how i would go about building a tea co2
laser that has such a small pulse width that it will be able to ionize the air enough to make a conductive path im aware UV is better at this but HeNe lasers have such horrible efficiency

i can also conclude that i will need to implement a q-switch into the laser to achieve the pulse width required to ionize the air


as for the tea laser im wondering if i should go for an old skool Jacques Beaulieu design IE using multiple electrodes under resistors to force the "glow discharge" or Rogowski-profiled electrodes using a pre-ionizing discharge


i would love to keep it simple IE slab laser type construction

i already have X2 slabs of tempered glass im just hesitant to attempt to construct anything without more knowledge on the subject
 

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You could PM a member here.... jarrod694 . He is very experienced building N2/Tea lasers. :)
Oh and welcome to LPF.
 

HIMNL9

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I justy hope you pay attention to not touch or short that cap bank, once charged ..... (KABOOM)

Anyway, as far as i know, those lasers don't need so high currents, they need high voltages ..... and it's not a TEA CO2 laser, or is a CO2 laser, or is a TEA laser (totally different things ;))

;)
 
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This is what i mean by TEA laser

Transversely Excited Atmospheric Pressure CO2 Laser

consists of parallel electrodes at or above atmospheric pressure

problems are that without a vacuum the HV dose not like to spread out evenly over the electrode it tends to form high current arcs so even tho you can get 10X the power or more from this type of laser apposed to the common vacuum tube co2 laser everyone makes getting the cap bank to discharge evenly can be a problem

im more worryed the cap banks inductance then i am the voltage cuz i can always just string more in series =P

and ya i tested it and Kaboom like a pipe bomb in the form of electricity

also thanks for welcoming me this will be my first laser build but i made a few tesla coils and coilguns before
 

HIMNL9

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Oh, ok, understood ..... was convinced that you mixed TEA nitrogen and CO2 lasers, sorry ;)

But, still these units needs 5 to 10 Kv PSU, right ? ..... maybe your problem is right this ? ..... i mean, once ionized, the arc zone is conductive enough to short your cap bank ..... maybe with much lower capacitance (at higher voltage) you may get better results ?

I mean, with 20 of these caps in serie (they are usually 220uF 385VDC), you can get a 10uF 7,5KV unit .....

Again, careful with these energies, they can kill, and not as joke .....
 
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"I mean, with 20 of these caps in serie (they are usually 220uF 385VDC), you can get a 10uF 7,5KV unit"

there 420uF 385v units but i overcharge them to 400v
wow it would be cool to see if 20 of those in series would stand up to there own discharge
but a 7,5kv 20uF unit half the size of a cinder block would be awesome now all i need to do is figure out how to turn that all into a inferred beam and Q-switch it

and i practice the one hand rule so worst case scenario i blow a finger off

and ur probably right i don't think 800v is enough voltage so odds are in going to end up stringing them into a 5kv bank
right now im unsure whether or not a photo flash capacitor even has the inductance required to allow for a glow discharge in a pre-ionizing TEA co2 laser even tho there designed for fast discharge
 
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HIMNL9

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As suggestion, when multiple capacitors banks are runned in serie, each one must have his own "balance / discharge" resistor in parallel ..... usually a 180Kohm to 220Kohm 1/4W resistors on each capacitor are enough, when they are all identical ..... also, always use identical capacitors, for this, cause it's a bit more "critic" than for parallel use ..... i mean, if possible, always from the same production lot (but i know that is really difficult to find them harvesting from photoflash machines), anyway always from the same identical brand and model of photocam, so the type of capacitors are the same .....
 
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something more along the lines of this would be more in my category but thx right now im looking for input on how i should go about assembling a TEA Co2 laser that can achieve a uniform glow discharge
 

LSRFAQ

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something more along the lines of this would be more in my category but thx right now im looking for input on how i should go about assembling a TEA Co2 laser that can achieve a uniform glow discharge

Your ESR on those caps is way too high for a pulsed C02.
 
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You overcharge caps, but I'd recommend to stay under their ratings. Imagine one shorting out after a while, the whole cap bank will discharge into that cap.
 
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5kJ...dude....you need doorknob capacitors and not even nearly that much energy.
Get some good doorknobs...flat wide terminals.

Optics might become a problem as well. Ocs are made of coated ZnSe, the HR mirror....Gold, Germanium...no Al or Ag...wouldnt risk it...might work, but aim for gold ^^
 
Joined
Oct 11, 2010
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Search in Google for the following article:

"Simple Inexpensive Laboratory‐Quality Rogowski TEA Laser"

Has very detailed instructions on how to build such a laser.

Willie
 
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There are a few very simple rules you just cant break.

Inexpensive and "simple"...the more loose the set-up is, the more luck OR skill you need ^^
I would buy 3 plates of plexi and aluminum L-profiles...blank...not anodized.

Its so easy you dont even need instructions....most of them are just confusing.
 
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Could you not use diodes on the capacitors to prevent them from discharging into a faulty capacitor?
 




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