dave writes:

On 09/10/2013 07:15 AM, wrote:
Hi Folks,

I'm a high school physics teacher, and just found an ML855 HeNe Laser from 1989 in a storage closet at my school that I'm trying to get to energize. My degree is in electrical engineering, so I'm not unfamiliar with troubleshooting electronics, but I've never worked with laser electronics, especially not from the 80s. The device requires a key to activate a switch, which I cannot find, but I was able to use a paperclip, while the device was unplugged, to attempt to rotate the lock mechanism into the "on" position. Now, I'm not sure if this rotated the actual switch or just some part of the lock, so the source of this entire problem could be that I am missing that key. If this is so, how could I obtain a replacement key for this unit?

If this is not the case, and you think my "jimmy the lock with a paperclip" method should have turned it on, does anyone know of any common failures with this model laser? The power light on the back does not even turn on, so if it is a failure, I imagine it's with the power supply.

Any and all suggestions would be appreciated.

Thanks


They go soft if you don't use them. The gases get unmixed. You may get
it to come back but probably not.

IF they are soft-seal. If newer than around 30 years of age, they will be
hard-seal with an essentially infinite shelf life.

Running a soft seal tube that has a decently bright discharge may get it
to come back to life after anywhere from a few hours to months.

--
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