HeNe advise

[dnar]

Does any one know what the voltage and current for this tube should be? I suspect the tube has been replaced at some stage and the invertor may not be ideal for the tube. Output is over spec and the tube runs hot to the touch after an hour or so. Is this normal for a HeNe tube?

Cheers.

[Displaser]

Output is over spec and the tube runs hot to the touch after an hour or so. Is this normal for a HeNe tube?

Cheers.

What are you using for a power meter? Is it calibrated?
I've had HeNe tubes that were fairly warm after use, so I'm not sure that's a problem.

[kitatit]

Hi Wayne,
I'm not sure about this model and my memory if a bit foggy but on the 12" long tube I was playing with that was around 5mW (I never measured it) I think it was around 1600v and 5mA.

Hope that at least gives you a point of reference. Hopefully our mixed gas friend can dial you in a bit closer when he spots this.

Good luck
Kit

[absolom7691]

19mW, I would think the voltage/current is a bit higher. I had a 17mW HeNe running on a 3200VDC 7mA Laser Drive brick. If I remember correctly, it is difficult to overdrive a HeNe. If the current goes too high, the output drops. Also, HeNe's do run fairly hot. Not too hot to touch, but warm enough to be uncomfortable.

[dnar]

Thanks guys. So, if they normally run hot can they run long term CW? Or do they time off ocassionally to cool?

[Jem]

I've run my 35mW HeNe's for days at a time. Come to think of it I once left an 8mW HeNe on for a couple of weeks (forgot to switch it off before I locked my shed ). All still work absolutely fine

The 35mW HeNe's need to be left on in order to reach a stable temperature for my holography setup. If they're not warm it throws the alignment out on my optical table, I always allowed at least three hours for everything to stabilise when I was using HeNe. I've now moved on to working with a 532 Coherent ring laser

[dnar]

So, being a magnet for laser parts, someone found a Laser Drive inc model 111-1600-4.5-TTL-1 HeNe PSU. It takes 12VDC, puts out 1600VDC @ 4.5mA.

Does anyone know of these? I am wondering if this would be a better supply for my Melles Griot tube?

[polishedball]

Thanks for sharing. That's a neat setup!

[dnar]

Here is a pic of the Laser Drive PSU I scored. 1600v 4.5mA. Do you think this is suitable for the MG tube above?

https://www.dropbox.com/sc/v1vcutgwoqww6e5/30o_SUbCxH

[buffo]

That might be a little weak. Looks like you've got a ~ 15 inch long hene tube there. My guess is that it's going to want more than 1600 volts. The current is fine, but the voltage sounds a tad low. I've got several tubes similar to yours, and I normally run them on either 1900 or 2200 volt PSU's.

That being said - hook it up and try it. If it won't light, or if it just flashes, then you know you need more voltage. But you might get lucky.

Adam