Argon Ions - oh how I have learnt so much about those.
Lets see now.
First of all if your going to get an argon ion laser, you'll usually come across two different types - single line and multiline. Single line argons emit one wavelength, and multiline several. You can test if your laser is multiline or singleline (ML/SL from here on in) by shining it through a diffraction grating, diffraction mirror, a prism, or in a pinch at a compact disc. Multiline lasers will reflect their multiple wavelengths as a row of dots. I still haven't caught up on the numbers for the nm's they emit. 488nm however is the most common SL and most dominant argon line.
When your out shopping for an argon, theres two things you HAVE to check with regards to the power supply.
1. Can I power it?
2. Is it in the same range as my outlets?
3. Do I need a spare space heater in the house...
For #1, don't grab that cheap monster 5 watter if its 3 phase, if you don't have the utility to power it.
For #2, check to see the lasers power supply will run of your line voltage - its no good getting the laser home and finding the psu is a 220v model and your line voltage is 110 - the other way around can be sorted with a beefy step-down transformer (don't worry, I've done it!)
The most common lasers you'll find in surplus argons are the JDS uniphase units, and the ALC 60X. NEC's are popping up often enough too. On rare occasions, so do ILT's (including their whitelight models *drool*)
Small argons that the hobbyist is likely to come across need forced air cooling. Lots of it. Thats why theres at least one honking big fan in just about every small ion laser pic - they generate a tremendous amount of waste heat, and the tubes will melt down quickly without it (assuming the thermal protection isn't working LOL). I used to use mine to heat my room in winter before I sold it! A good ML tube can do over 150mw, and up into the low 100's for a SL unit. They have a heated cathode, and the tubes can take up to a minute or two to click into life - they're not like HeNe's that wink on as soon as you hook up power (provided the HeNe has no CDRH saftey delay).
During this warmup time the filament is coming up to temperature and; in a linear design supply, the filter capacitors are precharging to ~100 volts; for larger lasers this can be up to 300 volts. Both large and small frame ion laser power supplies will kill you if you tinker around inside them. Capacitors can dump thousands of amps in a short period, and blow off digits if you survive. Best leave the lid on the supply
Lasers like these like to be run once a month for 20 minutes to an hour to keep them happy otherwise argon gas migrates into the tube walls, the pressure goes up and they become hard to start. Called a maintenance burn, its a monthly procedure that most argon owners remember to carry out - hence we often post reminders in the gas forum to fire up those argons.
A burn is a justifiable term as the plasma in the tube burns hotter than the sun hence the need for the 150+cfm fans on some models. If your REALLY lucky you'll come across an Ar/Kr (argon/krypton) unit that is called a white light laser. Different mixes of the two gases give different ratios - some tend to favour the red/yellow krypton line over the blue/green argon lines.
If you end up with a JDS Uniphase Argon or an ALC 60X, the remote controllers are easy to build. You can then use this to vary the tube current up from idle around 4A to 8.5A (thats the safe range) or boost it to 10.5A if you dare, but this shortens tube life dramatically so keep those 10.5A burns short.
*phew*
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