Yet another non-functional SP-161 argon...

[buffo]

Ugh... I need to vent my frustration.

Backstory: I blew up a power supply (261B) for one of my small single-line argons about 4 months ago while doing something stupid. I was testing out a new Spectra Physics S-093 tube that supposedly had multi-line optics installed. (The mirrors are hard-sealed to the tubes on these Spectra Physics units.) So anyway, I rip the head open on one of my 161's and install the new tube. Only problem is that the tube mounting sled is slightly different, and it won't fit in the head just right. No problem, I'll just leave the cover loose and set the sled in there really carefully.

Powered the thing up, and it would only flash. Ok, probably a high pressure tube. (Though it could also be low pressure, near end of life...) I'm cranking up the current control hoping that I can get the sucker to light up and run. (That way I can bury some gas and bring down the tube pressure.) But I'm forgetting about the half-ass way I've set the tube in the head...

Sure enough - Snap! Pow! The anode arcs to the baseplate of the head (ground). I shut everything off, re-install the original tube, and close everything up like I should have done before. Power it up, and now the original single line tube will only flash! (It was working just fine before.)

Crap... So I figure I've blown something in the main part of the PSU. (Clearly the ignitor is still working, but it can't maintain the discharge.) After poking around inside for a while, I can't see any obvious signs of failure, so I decide that I'm never going to find the problem myself and I shelve the whole thing.

Fast forward to about 3 weeks ago, when I purchased a used 261B PSU off E-bay. Great! Now I can get this laser working again, or so I thought.

So tonight, I decide to make it happen. But after about 3 hours work to repair the jones plug connector on the PSU (had to swap it out with the one from the dead PSU), I learn that this E-bay PSU doesn't work either! SHIT!

It powers up just fine, but when I flip the emission switch, the standby and interlock lights come on for a second and then dim back to nothing in about 2 seconds. I can hear the PSU click after aboput 30 seconds, which normally would fire the ignitor, but nothing actually happens. I'm afraid that something is fried on the board behind the LED's on the left side of the PSU (which is why the LED's are dimming out). But the last thing I want to do is dive back into that thing and start swapping more parts from one PSU to the other. (I already tried swapping the two main riser cards in the middle - no luck.)

So now I have 4 Spectra Physics PSU's, 3 heads (plus one spare tube), and only 1 fully working laser! (Not to mention my non-functional HGM 5) SHIT SHIT SHIT!

It's times like these that make me really appreciate solid state lasers.

Adam

[dave]

I assume the power supplies are linear? Linear supplies shouldn't be too hard to repair

You need to try your hand at some fault finding Adam

[buffo]

Yeah... I just don't relish the thought of diving into the guts of these PSU's.

But I'm going to fool around with it some more this afternoon. I'm going to swap the control boards on the far right side that house the LEDs, the current control, and the mode switches. We'll see if that helps.

I think the problem with the one that arced to ground is in the final passbank. Unfortunately, in order to test that theory I've got to desolder a bunch of components. Sigh...

Adam

[Zoof]

Hi Buffo,

I once bought a SP-161B with 261 PSU. Nice little argon at 488nm or so I thought. The guy who sold it to me put a sticker on the case labeled (220V, 16A) but the darn thing was configured for 115V inside and I found out by blowing it up (all lights went out etc.) The seller could only reply in German "You don't have a clue about lasers" capitalized in German :? I guess I should never have trusted the label. So this seller sold more of these units on ebay and I contacted a Danish buyer who had the same problem only he had opened the PSU and configured it for 220V before powering it and the laser appeared completely dead. His next thought was well, they might have changed something else so lets go back to the original 115V config and try. BANG only his was bigger than mine and his whole passbank was black!
When I started digging in my PSU and found that some PCB copper was burnt and one of the MOSFETS was blown and there was a TRIAC where there should have been the forth MOSFET. I figured I give replacing all MOSFETS and a couple of zeners a try and it worked partially. The laser has its ignition pulse but rarely starts. I got it to lase twice with a very weak multimode beam. The tube voltage was 97V but I never got to measure the current. Also the LEDS are not functioning as expected. Mine don't go out but simply stay the same all the time, even during lasing.
Anyway my suspcion had grown that the seller had sold a dead laser to begin with and as soon as I started to take steps against him through Ebay he dissapeared (don't know whether voluntaraly or forced). Lucky for me Ebay justified my claim and have some of the money back. Still stuck with a dead argon awaiting repair once I get my hands on the manual and have some time. A great learning experience though!

Matthijs

[cruch]

I got an SP 261B PS that is 115V. Have never tested my laser since we have 220 here.
Was thinking of buing a 2000watt stepdown on ebay.
I guess that will works. Cant find a 261B PS 220v on ebay

Also got an SP 163 head without powersupply..but I will receive one shortly.
Someone mentioned that I need a remote or something to get it to work?
Have no clues what that is for..
Anyone knows?

[Zoof]

I got an SP 261B PS that is 115V. Have never tested my laser since we have 220 here.
Was thinking of buing a 2000watt stepdown on ebay.
I guess that will works. Cant find a 261B PS 220v on ebay

Those 220V PSU are wanted, will be hard to find one cheap on ebay.

Also got an SP 163 head without powersupply..but I will receive one shortly.
Someone mentioned that I need a remote or something to get it to work?
Have no clues what that is for..
Anyone knows?

The remote is needed on the 261B for the interlock which prevents the laser to start without the remote. Most people don't have a remote and just short the appropriate pins in the connector since all other setting can be done on the PSU directly. For the 163's PSU it may be similar.

[cruch]

maby someone what pin to short?
Thanks for the info Zoof..

[buffo]

Cruch:

Sam's laser faq has some good information on the pinouts for these small spectra physics lasers and PSU's. I've sucessfully built my own cable to connect a 163 head to a 261 B PSU. (However, it took me three tries to get it right!)

You're right in that you can bypass the interlock by shorting a couple pins on the remote connector. The pins are different depending on which PSU you have. (The smaller 263 or the larger 261 B) I'll need to poke around with a multi-meter a bit this afternoon, but I should be able to figure out which pins you need to short on the 261B. (I actually have the remote pannel for mine.) On the 263 it's easy, because my unit already has the jumpers installed. (I just need to look at it.)

Zoof: Sorry to hear about your unfortunate experience on E-bay. I just bought a spare 261 B crom CompuSVC on E-bay, and it looks like it's dead. (Took a chance with an "as is" auction...oops!) I'm hoping to scavenge parts from it so I can at least get my other one working. (The one that died after the Anode arced to ground.)

Also, I found someone here on the forums (Weak Station) that is pretty familiar with smaller-frame air cooled argon units, and I hope that with his help I'll be able to resurrect at least one of these units. Perhaps we could all learn a little from him - unless you think your unit is completely fried, Zoof...

Adam

[cruch]

I won this powersupply for the 163 head http://cgi.ebay.com/ws/eBayISAPI.dll...5335&rd=1&rd=1
Hope this works

Buffo: same ebayer?

[buffo]

Yeah, that's the same guy... Here's the link to my auction:

http://cgi.ebay.com/ws/eBayISAPI.dll...m=180048977859

I just noticed that he actually offers a 30 day DOA warranty. oops. Guess I should have checked out the unit a little quicker! (Though it really wasn't possible to do so, since the 15-pin jones plug was missing some pins. I had to swap connectors with another power supply before I could connect my head to it.)

Let me know how it goes with your unit Cruch! I'll get you the pinouts when I get home...

Adam