Broken Burleigh WA20-VIS (I know Sam has used these before)

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Hello all,

We just got this retired WA20 wavemeter donated to our lab from Los
Alamos.
I haven't cracked the case open yet but when I plug it in I hear a
revving noise which I'm guessing is a bad belt.
Considering the cost of these machines as well as their sensitivity I
was hoping to find somebody with a tech manual I can go over before I
start this project.
EXFO, the company that acquired Burleigh doesn't have any
documentation on their site available. I'm going to phone them but I'm
guessing I'll come up empty handed... this has been discontinued for
too long I guess.

So... before I bite the bullet and open this up I wanted to gather as
much info as I could.... has anybody here ever repaired the belt in
these things? Any tips? Alternatively, does anybody have or have
access to a tech manual?

Thanks for reading,
-Matthew

 

[Sam Goldwasser]

We just got this retired WA20 wavemeter donated to our lab from Los
Alamos.

I haven't cracked the case open yet but when I plug it in I hear a
revving noise which I'm guessing is a bad belt.
Considering the cost of these machines as well as their sensitivity I
was hoping to find somebody with a tech manual I can go over before I
start this project.

Open the bottom. Most likely, you'll find the belt stretched out and
sitting on the bottom cover. Replace it with anything that fits and
you'll be good to go. An elastic band will work well enough to test it.

EXFO, the company that acquired Burleigh doesn't have any
documentation on their site available. I'm going to phone them but I'm
guessing I'll come up empty handed... this has been discontinued for
too long I guess.

So... before I bite the bullet and open this up I wanted to gather as
much info as I could.... has anybody here ever repaired the belt in
these things? Any tips? Alternatively, does anybody have or have
access to a tech manual?

http://repairfaq.cis.upenn.edu/Misc/Lasers/burleigh/WA-10_20.pdf

It's a wonderful machine. I just wish it was about 1/10th the size!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Matthew Karam]

Open the bottom. Most likely, you'll find the belt stretched out and
sitting on the bottom cover. Replace it with anything that fits and
you'll be good to go. An elastic band will work well enough to test it.



http://repairfaq.cis.upenn.edu/Misc/Lasers/burleigh/WA-10_20.pdf

It's a wonderful machine. I just wish it was about 1/10th the size!

--- sam | Sci.Electronics.Repair FAQ:http://www.repairfaq.org/
Repair | Main Table of Contents:http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ:http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites:http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

Thanks Sam,

Opened it up and, just as your suggested, the belt was lying there.
The noise is caused by the motor running without tension.
Next problem: somebody got pump oil all over the vacuum chamber... but
I know how to correct that.

Cheers,
-Matthew

 

[Sam Goldwasser]

Thanks Sam,

Opened it up and, just as your suggested, the belt was lying there.
The noise is caused by the motor running without tension.
Next problem: somebody got pump oil all over the vacuum chamber... but
I know how to correct that.

Yeah, probably left it connected to the pump with power off and forgot
to close the valve.

Take care cleaning the optical components (if they got oiled as well).

While it's open, you might as well do the alignment described in the
manual.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Matthew Karam]

Alright... I got the new belts thanks to McMaster's fast shipping
(hats off to those guys, always so quick).
Now my next big problem: the motor is broken.

It should be easy enough to replace. Judging from how this machine
works, I don't suppose that it's dependant on the speed on the motor.
It's just counting and comparing fringes...
I'm thinking I'll try to put a little graphite into the existing motor
but my guess is that I'm going to need to replace it.
I'll take it out, plug in a volt meter and see if I can find another
motor hat runs about the same speed on the same juice.
Ugh, what a pain.

Any ideas?

 

[Matthew Karam]

And to top things off.... it's a 120 volt motor sync motor. Gonna be
fun to find a replacement for this.

 

[Matthew Karam]

I spoke too soon. I took apart the motor, cleaned out all the bits of
broken magnet dust and gave it a little oil. It's spinning like a
champ now.

 

[Sam Goldwasser]

What do you mean: "broken". Doesn't run or makes a lot of noise or what?

Cleaning and lubing the bearings might cure the latter.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Sam Goldwasser]

See?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Matthew Karam]

Yup, the reference is working now. All the optics are aligned...
adequately.
The output doesn't give me anything that looks like a nice sine wave,
but that's all in the screws

 

[Sam Goldwasser]

Yup, the reference is working now. All the optics are aligned...
adequately.
The output doesn't give me anything that looks like a nice sine wave,
but that's all in the screws

And the pump oil residue?.....

What do you mean by "the reference is working now" beyond the HeNe laser
being on?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Matthew Karam]

The vac chamber is clean with the help of kim wipes and ethanol (the
manual explicitly says not to use acetone).
I mean the REF ERROR light is off, so the HeNe is working *and* the
alignment is ok.

 

[Sam Goldwasser]

The vac chamber is clean with the help of kim wipes and ethanol (the
manual explicitly says not to use acetone).

Yeah, because I guess the optics will fall apart.

I mean the REF ERROR light is off, so the HeNe is working *and* the
alignment is ok.

There's not much else to go wrong.

If you push the test button, do you get the HeNe wavelength?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Matthew Karam]

I do get the HeNe wavelength with the test button. My task for today
is to shoot in another reference laser and verify that the wavelength
is reported properly.


Thanks again for all your help, Sam. This would have been a major pain
without your help and your manual.... do you just keep archives of
these things?

 

[Sam Goldwasser]

I do get the HeNe wavelength with the test button. My task for today
is to shoot in another reference laser and verify that the wavelength
is reported properly.

The beauty of this thing is that once you get that to work, almost everything
else *has* to work. It may not be optimally aligned but should be close.

Thanks again for all your help, Sam. This would have been a major pain
without your help and your manual.... do you just keep archives of
these things?

Yeah, somewhat randomly archived across various Web sites.

Thanks!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.