MELLES GRIOT 05-LLR-831 10mW max HeNe Laser - eekBay

[Sigurthr]

4mA may not be enough for an old tube, just fyi. Most high mileage 5mW tubes like >5.5mA, sometimes up to 7mA when they are closer to death. Also, if they really are 10mW tubes they would definitely need more than 6.5mA. All this info is in sam's laserFAQ.

 

[mattco2]

that was to be spliced with his current psu and the ballast set accordingly

 

[Sigurthr]

that was to be spliced with his current psu and the ballast set accordingly

Ah, I misunderstood your comment. Yes, adding 4mA in parallel would probably work out fine.

 

[mattco2]

but that tube is near-death a replacement might be cheaper