jvb7u@astsun.astro.Virginia.EDU (Jon Brinkmann) (12/14/90)
I've often wondered what the failure mode is for fluorescent light bulbs. It all came back yesterday when one or both of the U-shaped bulbs failed in the fixture in our kitchen. BTW, they are $10 each (I'm tempted to trash the fixture and buy one that uses straight tubes)! It had been running fine for a couple of hours when it flickered and made a ticking sound and started flickering dimly. I measured the continuity between the pins at each end of the tube thinking that it might be a broken pre-heater filament, but the continuity was good. Can anyone out there help? Jon --- -- Jon Brinkmann Astronomy Department Internet: jvb7u@Virginia.EDU University of Virginia UUCP: ...!uunet!virginia!jvb7u P.O. Box 3818 SPAN/HEPnet: 6654::jvb7u Charlottesville, VA 22903-0818
news@pasteur.Berkeley.EDU (Six o'clock News) (12/17/90)
>I've often wondered what the failure mode is for fluorescent light >bulbs. From: e221a-bx@crux.Berkeley.EDU (Charlie Sullivan) Path: crux.Berkeley.EDU!e221a-bx The usual failure mode is for the emission material on the cathodes to get 'used up.' It gets bombarded by ions during normal operation and especially during startup, and gets chemically degraded and/or evaporated. The tungsten filament often stays intact, but tungsten doesn't emit electrons near as well as the special goop they use. >[...] It had been running fine for a couple of hours when it >flickered and made a ticking sound and started flickering dimly. Ticking sound could be the starter. A bad starter might do this itself, or a good starter could do it when the lamp (lighting jargon for light bulb-- they call the whole fixture a 'luminaire') dies. I can only recommend swapping out the bulb, and if that doesn't do it, try the starter. Charlie Sullivan charless@cory.Berkeley.EDU