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FrozenGate by Avery

HeNe PS woes..[solved] photo update:JDSU 1135P dissection/decanned

icecruncher said:
My guess is that the tube is fine, but the power supply shorted and ended up not being very happy..

The arcing probably caused some issue. What? I don't know.

With it arcing, it may have stayed in the initial start voltage for a long time or shorted, thats my best guess.
Click to expand...

Yeah, that's a likely possibility. It might not be even fixable if that's the case because in the lab PS contains a brick and if I'm not mistaken they are sealed...
 
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The Voltex supplies are pretty tolerant of shorts, but if it was whining it might be a HV leak, check your wiring. use solder clips, dont just wrap the wires around the mirror mounts, the bad connection will stress the supply if it doesnt have good contact. its also possible the HV module is defective. DO NOT run it on a Variac. its is a switchmode supply, the variac would only help with a linear supply.
 
Try to also replace that anode wire with HV cable e.g. from a TV CRT LOPT transformer output (EHT/Flyback transformer). That stuff is rated to some 50,000 volts and nice and flexible. Its the fat red wire leading to the cup on the back of the TV tube. House mains flex isn't that suitable as any tiny defect in the insulation may lead to corona discharge. Silicone (non conductive) goop on any exposed connections in that lead (except the mirrors) should be able to prevent corona discharge.

The air forms a large capacitor which is an easier path for the high voltage to go (within reason) and we don't want this.

remember electricity always seeks the path of least resistance to the other electrode / ground.
 
ultimatekaiser said:
The Voltex supplies are pretty tolerant of shorts, but if it was whining it might be a HV leak, check your wiring. use solder clips, dont just wrap the wires around the mirror mounts, the bad connection will stress the supply if it doesnt have good contact.
Click to expand...
I meticulously cleaned the rings on each end and resoldered the wires to those contact rings. I'm sure there is a good connection now.
The connection from the Alden pug is fairly decently spread apart now, no arcing.


vk2fro said:
Try to also replace that anode wire with HV cable e.g. from a TV CRT LOPT transformer output (EHT/Flyback transformer). That stuff is rated to some 50,000 volts and nice and flexible. Its the fat red wire leading to the cup on the back of the TV tube. House mains flex isn't that suitable as any tiny defect in the insulation may lead to corona discharge. Silicone (non conductive) goop on any exposed connections in that lead (except the mirrors) should be able to prevent corona discharge.

The air forms a large capacitor which is an easier path for the high voltage to go (within reason) and we don't want this.

remember electricity always seeks the path of least resistance to the other electrode / ground.
Click to expand...
I can try some better insulated wire, great tips on where to source some.

However, now guys my attention has shifted from the tube to the high dollar lab supply. Tubes are cheap on eBay, that vortex PS wasn't:/

The supply came as a package deal with a uniphase greenie. Before the pair worked perfect. Now Ps makes a screeching sound then shuts down. Tomorrow I might give chad a call at MI to see if we can trouble shoot it or he could repair it.

It might have been taking some abuse. Cycling on and off trying to get the tube(decanned red) to start up. Shorting out multiple times when I was splicing wires...
I really enjoy gas lasers, but it's daunting to see them fail.
 
Generally when you shut it down it should be quiet. The whine is from the rapid HV bleed-down. it generally shouldn't do it with the tube, but if I run mine without an Alden connected by accident, it'll sing when I shut it down as it bleeds off the larger than normal start pulse. I have a high-voltage 4.1KV MG supply that does the same thing when I turn it off.
 
Oh no let me clarify, it's not the bleed down. It whines when it runs than it powers down on its own. I only did it once I don't want to make anything worse. it only started this after the shanagains with the decanned tube.
 
Yes if it's doing it regularly even with the lower powered tube the The internal high-voltage module is probably arcing over and needs replacement from stress. Call voltex it's pretty easy to replace. If you just bought it it's probably still under warranty, I had to call them to replace the noise filter in mine when I accidentally blew it out, out of warranty. They fixed it for cheap (about $52 iirc which is typical of one at several amps), were very helpful and had a very fast turnaround.
 
****update*****
There was damage to the power supply most likely due to arcing where I spliced in my wires. I separated them and taped them back. I also have some HV leads from a dead brick that should provide substantial insulation.

Fast forward to now-I had my module in the Voltex fixed and I decided to hook up this laser! This hopeless hard to start tube fired right up and stabilized after a flicker. Now it starts every time! Photos with a glass stirring tube.

I appreciate everyone's input and feedback





 
Congrats.

Glad its finally working.

happy you got all the pieces together.

Next one should be much easier :)
 
Glad its working now :) it looks a bit overly white in the pics though. certainly hope it doesn't look that way in real life! (probably the camera) wonder what power its giving you.
 
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Yes, the true bore color has a pinkish glow that looks similar to my other decanned tubes. Now I just need to get more bricks. I have 3 tubes and one voltex.
 
I think I have a few spares. they wouldn't be cheap, but I can dig em out if you're interested. I'll PM you what I find.
 
Glad you got it working. Bare HeNe tubes while a bit dangerous are a thing of beauty when running.
 
I'm a big fan of bare tubes. I'm sure if I wanted to spend the time I could engineer a plexiglass and wood frame that would insulate the anode and cathode while still providing a rigid support.
Hmm what gas laser to move onto next....
 
Ar-Kr is next on my bucket list of gas lasers but unfortunately small frame single phase ones aren't cheap.
 
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