a dream has become true - my first argon laser (ALC60x)

[MarioMaster]

Wow. That's a helluva deal! It's even more amazing you get that many lines on a tube that old. My JDSU tube will only do 6 lines although I swear before the first PSU blew up it produced 7.

AFAIK the JDSU argons (maybe only the cylinder heads) have mirrors which only allow 6 lines to lase although I had one that had a weak 7th line as well.

The other heads like the Omnichrome, ILT and ALC heads tend to do more lines from what I've seen.

To the OP: Great score for all the stuff you got As you can tell from my avatar, I'm a fan of ions.

 

[diachi]

thx, this time i've been a luck fellow! The argon is doing a good job :evil:

But so far no time to measure the anode-cathode voltage and full current.

Regarding the number of line I guess the "green" one should be higher. It starts to lase at high current only... don't know if this is a good sign or not...

Anyone with more expierence here?

May be some pictures of lasing lines?

I've heard that the spectrum will move more into the "blueish" if the tube comes near its end... (hopefully not).

The green coming out more at higher currents is normal. Green lines have a higher gain at high currents.

 

[mojo_1234]

today I'd some time to measure the anode/cathode voltage at different tube currents... and yes! the tube seems to be in good condition :eg::eg::eg:

around 112V at 10A tube current!!! regarding to SAM's this a good value for a 30 years old ALC!

If anyone else has some similar measurements - post it :wave:

During last weekend I did some alignment and the green line now comes at around 7A... *happy happy joy joy*

bright - brighter - brightest

 

[mojo_1234]

something I want to share...

during yesterday's measurements of the tube current and voltage the filament transformer voltage (this is the one to head the cathode) was much too low. Around 2.6V AC but it should be exactly 3.0V AC.

After doing some research and checking the "golden box" PSU I found that the filament transformer has five taps on primary side (marked with 1 to 5) which allows you to roughly adjust the voltage.

With exact 110V AC line voltage I did the following measurements (at 10A tube current):

pin 1 / pin 5 = 2,6V
pin 1 / pin 4 = 2,9V
pin 1 / pin 3 = 3,2V
pin 1 / pin 2 = 3,4V

And the correct filament voltage has a measurable and visible impact on the output...

To allow a faster setup later on I attached some wires to the pins 3, 4 and 5 (the three brown wires at the white terminal strip).

And again: I can't get enough of this wonderful stuff

 

[MarioMaster]

It's possible your line voltage is sagging under the heavy load of the argon laser. I should check the filament voltages on my lasers as well, but the uniphase filament transformers only have one extra tap (208/240v) and (100/120v) depending on if you have a 120/240 only psu or the gold box ones which have windings for all four settings.

 

[vk2fro]

My argon exposed one circuit in the house that wasnt up to the task. It would just click. I went around the house getting some exercise with a 750W microwave, a cup of water and a table lamp with an incandescent globe. Plug the 2 appliances into a power strip or double power point, put the water in the oven, turn on the lamp and then start the microwave on medium power. The water acts as a load for the magnetron.

The circuit in the house has healthy wiring and is at least up to the task of a 750W microwave if the table lamp doesnt dim when the magnetron in the oven kicks in. It may flicker at the magenetron transformers initial inrush, but should stay same brightness.

A 1200W fogger would do the same job, and be a tonne easier (pun intended) to carry around the house than a microwave (or an argon).

If the wiring isnt up to the task, the light will dim, with a shimmering flicker which is cause by being in such close proximity to a large inductive load.

 

[mojo_1234]

thanks for your replies...

the filament voltage is exactly between 2.9 and 3.0 volts if the transformer is connected to tap 1 and 4. The line voltage doesn't drop significantly between 4 and 10 amps tube current and stays at around 110V (109 - 111V).

GUESS THE PSU JOB IS DONE...

But there's one more thing someone might know: Even the laser beam has wonderful specs (mode, divergence) there's some strange pattern/beam waist around the laser beam itself.

It has some "chessboard" like structure and never saw something similar on other photos of other ALC beamshots. Just take a look on this beamshot (the "square" around comes from the bouncing mirror).


Does anyone of you has an explanation for this? Is this normal?

The intensity of the waist compared to the beam is very low (not as bright as shown on the photo)...

Thx!

@vk2fro: you're waiting for an argon? is it your first one? If yes, you will love it :beer:

 

[Cyparagon]

That looks like an interference pattern.

 

[LaserCo]

.........
Thats a really unique fan setup on that argon - like how you called it "Tarzan". Are you sure you didnt mean "Turbine"

@vk2fro The Tarzan fans are some of the very best fans you can get
for an aircooled argon, typically priced at around what this lucky
fellow got his whole setup described here for (~$120USD) and they
say Tarzan on them and have blades with teeth.

@mojo_1234 It surprises me that you are beginning to see another
line showing up at only 7 amps, wow, very nice and efficient! - and
it has sat for 10 years! so nice!

I would not run your filament above 3 Volts, I have experience in
rejuvenation of the NEC GLG3030 air cooled argon and learned that
running one with a higher filament voltage would lead to them
becoming hard to start - and it could happen very quickly.

I would not let the filament go beyond a nice dark orange, going
into the white was not good. I found a good initial startup point on
the pot would be a little bit past the idle point, hard to define
exactly.

As far as your corruption in the beam I have no answer for you, with
the checkerboard pattern.

Out of curiosity, what type of galvos did you score along with this
great deal?


That cooling shroud you have there is a nice one and I have never
seen anyone else with one but myself. Years ago I purchased thru
MWK and Omnichrome 532 (With that shroud), umbillical cord,
LaserMax (an ISA card) and BeamFX (DOS software) for....

.
.
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$4500 thats right!

 

[MarioMaster]

The strange beam light may be from a dirty pickoff sensor for the optical feedback system.

 

[mojo_1234]

jsut read the recent replies:

@MarioMaster
Unfortunately the beam sampler has already been removed

@LaserCo
the filament voltage is exactly between 2.9 and 3.0V. refering to SAM this is optimal. And I'm not going to "touch" it again

the scanner is a Catweazle LCII (at least 15 years old) including the required driver board and power supply. The manual mentions that the scanner is capable to handle 20k or 30k in case of °4

There's also some old fashioned ISA controller card. But if I go it right we have the year 2012 and who's still using a 15+ old hardware? Also the scanner software seems to be some kind of crap...

Here's a picture of the scanner I found in the web (Google):

I will add some pictures of mine today or tomorrow (or start another thread). Already ordered an external audio controller and let's see if I'm able to revive the scanner...

 

[diachi]

I would not run your filament above 3 amps, I have experience in
rejuvenation of the NEC GLG3030 air cooled argon and learned that
running one with a higher filament voltage would lead to them
becoming hard to start - and it could happen very quickly.


.
.
$4500 thats right!

I think you mean volts

 

[LaserCo]

I think you mean volts

Whoops! Yes I did!
I will edit it, thanks