Anybody Near San Jose, Calif ?

You cannot remove that mirror.

If the GITD stuff doesn't light up, then we may have to try adjusting the rear mirror.

I'm off to bed. I've got a class in the morning

Peace,
dave

The GITD stuff doesn't light up. When I power the unit up it appears to "try" to come out red, but then quickly turns blue.
How would I adjust the the rear mirror? I'm going to tear into another unit (i bought more than one ) and do a comparison. If it isn't fixable I guess I could make into a cool lamp. I saw a pic of one on here somewhere.


Thanks again Dave, for all your help and patience. I'm sorry for having to ask all these questions. :-/

Angel.

ColdStl said:

The GITD stuff doesn't light up. When I power the unit up it appears to "try" to come out red, but then quickly turns blue.
How would I adjust the the rear mirror? I'm going to tear into another unit (i bought more than one ) and do a comparison. If it isn't fixable I guess I could make into a cool lamp. I saw a pic of one on here somewhere.
Thanks again Dave, for all your help and patience. I'm sorry for having to ask all these questions. :-/
Angel.

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You "adjust" the rear mirror by simply "tweaking" it in a direction.  Be careful if you try this.  The metal part of the "tube" is negative and the rear mirror is positive  

I use a pair of plastic, HV pliers to tweak the rear mirror.  Don't twist hard.  Sometimes it is only a very small fraction of a tweak to get the mirrors aligned again.  PLUS, it is possible to snap off the glass "neck" of the tube.  Try all the directions and watch the output.  If you get a "beam" anywhere, concentrate on moving the rear mirror that direction.

With the type of tube you have there, you cannot remove the metal.  You could still make a "lamp" out of it, but only the small glass part will be exposed.

Let's hope the next one is better.

Peace,
dave

[highlight]**EDIT**[/highlight] I just thought of something else. It is also possible that the power supply has started to fade/fail. Since it "tries" to turn red and then fails, it may be that it will lase at the higher "start-up" current, but not at "run" current. Unfortunately about the only way to test that idea is to cut this one off and wire the tube to a different PSU or to have an HV probe to be able to measure the output.

I tweeked the rear mirror and the beam is red now! It's a weak beam, but it's red and works for me.  

There are two other power supplies; 115VAC 400VDC, and a power conversion custom rectifier- Input 115VAC 50/60 HZ 240 mA, Output +- 15V 150mA  5V 1000mA.

Dave, if these are something you could use, or want, they're yours. Just let me know.


Angel.

ColdStl said:

I tweeked the rear mirror and the beam is red now! It's a weak beam, but it's red and works for me.  
There are two other power supplies; 115VAC 400VDC, and a power conversion custom rectifier- Input 115VAC 50/60 HZ 240 mA, Output +- 15V 150mA  5V 1000mA.
Dave, if these are something you could use, or want, they're yours. Just let me know.
Angel.

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Sweet! At least we have a beam, eh? With some of my bare tubes it seems all I have to do is "touch" the rear to change the TEM mode.

If you don't have a use for the power supplies, we can find a home for them. I'll PM you my address.

Peace,
dave

hey so i got 3 of them also. one the beam works nice and bright red. the other 2 are doing the same thing that coldstl posted. i dont realy see a way to tweak the rear mirror. it doesnt move at all and no way to make it move. one of the units has a metal ring holding the front optics in place but they are still glued to the tube so dont know why its there.

Hi thecrazzyman,

(with the power off) I removed the black plastic cap that says DANGER HIGH VOLTAGE and pushed, not twist,(carefully) the exposed mirror and the tube it is attached to, in a direction. Then I replaced the plastic cap, powered the laser up and observed. I repeated this several times. Each time I pushed in a different direction, and eventually I got a red beam. It didn't take much of a push to tweak the result.
The beam wasn't as bright as it should have been and I believe daguin's suggestion of an old power supply may be the cause.

You might wanna try using the good power supply from your "working" HeNe and connect it to one of the others to see if it makes a difference.

Hope this helps,

Angel

thecrazzyman said:

hey so i got 3 of them also. one the beam works nice and bright red. the other 2 are doing the same thing that coldstl posted. i dont realy see a way to tweak the rear mirror. it doesnt move at all and no way to make it move. one of the units has a metal ring holding the front optics in place but they are still glued to the tube so dont know why its there.

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You just GENTLY move the whole metal end (that sticks out the "back" up, down, and/or side to side. It is NOT going to "move." It is only going to "tweak" slightly. You may not even "see" the movement, but it can affect whether it will lase or not.

Peace,
dave

thanks. from the posts i assumed you were doing that to adjust them. just doesnt seem like it would move much. but i guess you dont want it moving too much. i got 4 of them total and one had a broken tube. so been playing with the parts from the broken tube to see and understand how it works. also you noticed the thing at the laser end of the black alum block right? looks like a big diode? is it or is it a photo sensor. also the photo sensor detector inside the black alum block is preaty amazing too.
i plan to use the one working laser with optics as a laser microscope. just got to find the right optics to get the right beam. then i can look closely at the dector in the block and see what its all about.
thanks for the help and i will try it tonight.

thanks. from the posts i assumed you were doing that to adjust them. just doesnt seem like it would move much. but i guess you dont want it moving too much. i got 4 of them total and one had a broken tube. so been playing with the parts from the broken tube to see and understand how it works. also you noticed the thing at the laser end of the black alum block right? looks like a big diode? is it or is it a photo sensor. also the photo sensor detector inside the black alum block is preaty amazing too.
i plan to use the one working laser with optics as a laser microscope. just got to find the right optics to get the right beam. then i can look closely at the dector in the block and see what its all about.
thanks for the help and i will try it tonight.

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I was wondering if that was a diode as well :-?
Also..Does the unit with the broken glass have stains on the outer top (the cover)? I had to return a unit for having a broken HeNe (the glass). I hope they didn't sell that one to you. They will refund you for that unit but you will have to drive back and return it.

yea i thnk it does. thers alot of dust on them. i do like that thers a calibration chart on the inside. the working one i have is 5.1mw lol.
i dont realy care cuz i got the last ones. the people at svc were asking what they do and why is everyone buying them.
where do you live? im just north of san francisco in marin. so it was a nice drive down there. i just wanted to wander there warehouse and buy everything. i need a spectrum analyzer and they had them.

I live in Merced, so it was just under a 2 hour drive for me.

I don't think the people at svc even looked inside any of these units because each unit had different items missing from them. Some had mirrors and screws missing, others looked to have wires replaced/fixed. On top of that, they tried to charge me $13 handling charge when they originally quoted me $5.

I was wondering who bought the last 4, now I know (I must've beat you there on Friday. That's when I exchanged the dusty, stained, broken unit.) They said someone was on the way to pick up the last four units, otherwise I would've bought them too! ;D

BTW..I saw similar units on Ebay listing at $700...as is and untested.

hah yea i got down there friday at like 530. i paid 13 for each. ugg. but still fun drive and cool stuff. everything is inside thiese ones i think. i did notice striped screws and other messed up things but figured it was the techs who did it in 94. the paperwork inside them sais who had them too. svc has 2 other kinds of laser particle analyzer/counters for like 30 and like 70 bux i think.