Rick I would suggest getting the laser refurbed. As long as the plasma tube is not cracked it is easy for them to do. I would suggest contacting Phil at Evergreen Laser (www.evergreenlaser.com). He has done several I-90 rebuilds for me. When operating an I-90 in UV you have to be careful not to let the tube overfill which is what the over pressure means. If it overfills beyond a certain point it does away with the UV but may still operate in visible. Try switching it over to visible and see. To prevent overfilling disconnect the fill circuit and move it to the "spare" position on the main terminal strip on the side of the magnet on the tube (have to remove the cover to get to it). If the laser will operate it may burn off enough to get the UV back. Call Phil and talk this over with him to confirm what I say is correct. If you get it back leave the fill circuit disconnected. Ever once in a while you will have to reconnect it for a day to let it refill. If operating the I-90 in visible you don't need to keep the fill circuit disconnected. Good luck. Larry At 02:51 PM 2/1/2002, you wrote: >Hi, everyone: > >I'm running an EPICS Elite with a gated amplifier and 5 PMTs. We have 3 >lasers, one of which is an old Coherent Innova 90 which we have been using >for its UV wavelengths. Unfortunately, it has been running "over pressure" >for some time, and now gives me an "under voltage" error message. It now >will not operate in "light regulation" mode, so I think that it's >usefullness as a UV source is at an end. So, what to do now (with a >limited budget)? > >I've heard that there are air-cooled UV lasers now available. Do any of >you have experience using one of these for flow? Are they adequate for >doing calcium studies with indo-1 or DNA with Hoechst 33342? What >manufacture/model do you recommend? > >Or, are water-cooled lasers still preferred for flow work? If so, please >give me your recommendation for getting the plasma tube replaced in our old >Innova 90. (Or is there some reason not to try to repair the Innova 90?) > >Thanks in advance for your advice. > >Rick Meister >* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * >* Richard K. Meister Email: meister.1@osu.edu * >* The Ohio State University Voice: (614) 292-9716 * >* Dept. of Veterinary Biosciences FAX: (614) 292-6473 * >* Cytometry Instrumentation Lab * >* 1925 Coffey Road * >* Columbus, OH 43210 U.S.A. * >* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Larry W. Arnold, Ph.D. Associate Professor Director, Flow Cytometry Facility Department of Microbiology and Immunology Lineberger Comprehensive Cancer Center CB# 7290 University of North Carolina at Chapel Hill Chapel Hill, NC 27599 Phone: 919-966-1530 FAX: 919-962-8103
This archive was generated by hypermail 2b29 : Sun Jan 05 2003 - 19:25:59 EST