expertise needed identifying a large frame Ak/Kr coherent tube

**Mr.Coffee** · 10-07-2009, 20:04

Originally Posted by Laser Ben

LOL!

Coherent says you need a total of 5 people to lift a laser system which weighs ~120 lbs, 4 to lift the 90lb power supply, and one to lift the 30lb laser head! By their standards, you'd probably need the whole dam company to lift a large frame Ion laser!

There's a big difference between "lift" and "lift properly" or "Lift safely"

**shrad** · 10-08-2009, 01:04

hehe yeah I should put photos, but the problem is that I currently don't have internet at home, I only have a mobile phone with a crap camera, I still haven't found back my memory car reader, so I'm currently unable to have the pics I took online

what you are saying about the weight of the unit is true, it's really heavy, but we have a forklift here and a bit elevator to get it down the building

I think big blocks of foam under the unit would keep it safe from shocks, no?

for the beamlock part, I need to have a deeper look, and have no time currently (working on a quite complex research task, and being a non-research team member >_<) but I can say it has a built-in powermeter head, an adjustment assembly for the rear mirror, and something that looks like a rotating wavelength selector at the OC side, perhaps something based on a prism, before a shutter and an assembly with a small white pushbutton, don't recall if the word printed next to it was "beamlock" or "beamblock"...

anyway, if I can test it and even make it lase low power with my 220VAC single phase 38A line, I'll do what I can to get it to work

**shrad** · 10-08-2009, 05:08

up to the news

I have a 15kV NST transformer, access to many different variacs, and also have several high current low voltage secondary 230VAC transformers

has someone an idea of the filament voltage and current, discharge voltage and minimum current for it to lase?

I might have a chance to hook up a small (sic) test power supply, after having read a part of sams laser faq related to Ar/Kr and Ar ion laser psus

I also have access to large toroid cores to make an igniter coil, and the accorded capacitors... I might also be able to find a pulse transformer used for flashlamp triggering @ 25kV and accorded capacitors, too

well, basically what I want to be able to do now is calculate the total amount of power needed to run that beast at minimum idle power... I bet this is possible...

I'll have a look for that power supply for resell purposes afterwards, as I have no use of and no means to use that laser

I just have an opportunity to get it to lase I think, an rare opportunity in fact for someone who is looking to have a small ion laser and has never really manipulated such things

(be sure I know how to manipulate HV stuff, HV capacitors, live parts and the like

)

**shrad** · 10-08-2009, 05:36

this is exactly the same unit as here at sams laser faq: http://www.repairfaq.org/sam/laserpi...s.htm#spha2030

if you have suggestions about what to be done for it, please tell me

EDIT: small update, the power supply is there too, and it will be useless if they throw the tube away

might also pick up a bruker IFS-25 fourier transform spectrometer (fingers crossed fingers crossed fingers crossed)

**mixedgas** · 10-08-2009, 12:36

That has a 3.2V ac cathode. The DC for the tube goes down a center tap on the cathode transformer to balance the arc so one side of the cathode does not get eaten away/ Some place between 30 and 50 amps of cathode AC current.

Magnet is usually rectified 220V line to dc, and anywhere from 4 to 8 amps in SP products. Often SP products need a magnet regulator, so measure the cold magnet coil and get back to us, between Pat and I we can take a guess at what u need.

Anode of the tube is usually the north pole of the magent.

Smaller tube then yours, but...... I do not reccomend resistors or series inductors as power supply elements, it has been done,but is dicey at best unless you really know your stuff.
Note variac plus air cooled tube = dead tube, dont try this at home folks, Mike had his magnet in series with the tube, as some medical coherents used to, and this acted as a inductive ballast. Longer tubes tend to have a more positive I-V characteristic, small tubes have a negitive slope I-V characteristic and will BLOW UP without a series constant current source.

Mike's power supply had the famous 30-30 warrenty, 30 foot or 30 seconds, whichever comes first.

http://www.electricstuff.co.uk/biglaserfun.html

Steve

**shrad** · 10-09-2009, 01:23

thanks Steve, thats really valuable and makes me think it would be doable with my poor 38 amps of line current

now I have to gather the parts to make something a bit more complex, in order to avoid killing the tube, and to avoid the ripple I'll have running it from single phase... maybe some kind of giant ripple supressor based on differential windings? I'll keep thinking and keep you up to the info

**shrad** · 10-20-2009, 01:38

hmm the laser is not any more available to me...

people here realized they had a complete cavity design for free and they needed one, so....

I'd get the bare tube if I wanted, but that's too much a hassle for nothing

poor me, too confident... I was just stupid and will keep off ebay for a little time, as I'm at a high risk of appeasing my frustration with fast-bought goodies

**LesioQ** · 10-20-2009, 01:48

Don't be so down. If You had means to transport it, I have an argon SP-2025 gas intact with factory 208V PS in my garage, I 'd let go for 300EUR with any optics You like.
Last time I ran it it (2007?)was high pressure but not far from lasing.
I know it's not as long as Your dream-equipment, still it's a significant piece of equipment

Piotr.K

**shrad** · 10-20-2009, 02:21

wow, that's really an offer!

sadly, driving to poland is not really an option

(and I don't even have my driving license... yet)

the most appealing part of the deal was to get it for free, as I don't have any use for it... what I was planning was getting it to work a bit to proof it was gas intact and could lase, and resell it to get some money and help other projects grow a bit

what I have to do now, as I have the house, is getting my workshop built slowly... and I was looking to buy some good grade materials with that help ^^

I'll have to buy concrete and cement blocks now, and get to work to renovate that old annex of my house... the wife will still be angry about lasers invading the place for some years ^^

**Laserman532** · 10-20-2009, 08:15

you have a house and a wife but no drivers license

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