I've got two warm white MainLighter lamps of different ages that just glow dimly on the ends, regardless of HPF or NPF ballast. Each has a slightly browned end (one end only, opposite the etch). Is this just typical of Mainligher EOL? Or do my ballasts that underdrive F40T12 lamps simply not have enough OCV to fire up old lamps that have quite possibly sat without being powered up for decades?
They were tested on an old shoplight with one of those old BenchLite NPF ballasts and in a wraparound with a MagneTek (I think HPF judging by the slow, smooth, entertaining startup flicker.) I'm sure it's not full power .8 amp though.
Any ideas guys? Would running them on an F32T8 electronic IS ballast briefly "shock" the lamps into life? I would think if they had no vacuum nothing would happen, but if it was a slow air leak (possibly for years) and since they were only powered up momentarily the filaments might not have vaporized, but I doubt that's the case.
Luckily I'm getting like fifty of these, so some should work!
Any ideas florescent experts?