A box of new Sylvania F20T12 Warm White bulbs, from the early to mid 80s?.  All new bulbs!  




This 32 Watt T-12 bulb had a very intense End of Life!  It was doing it's death dance for a good 30 minutes before it finally went out completely.  What made it interesting is that after awhile of one end spiraling and doing the red phase, the other end started doing it as well!  Was on a single bulb fixture with a 30+ year old Universal ballast.  (To be replaced with T8 fixtures within the next year or so) Notice how dark it got on the end without the stamped logo.  





Here is a late 80s/early 90s vintage Philips "Colortone" F40T12/C50.  I have 2 of these in a church building to offer a unique shade of blueish white.  Got these off of E-Bay a few years back.  The other 2 already reached EoL rather quickly and have been disposed of.  

I seen Sylvania 40W lifelines on switch start at my school (lamps >20 years old and been in use every day) begin rectifying and flickering, then come back to life for several days up to several weeks (with the black end from the bad cathode) before finally beginning to rectify again

Great quality tubes

Philips one = A9 = 01/89

I like those GTE Sylvania WW lamps! 

Time for some more!

Name the maker of this one.  I have 4 of these bulbs installed in "always on" fixtures.  





The above bulb installed in the "always on" fixture, which also has an emergency battery back installed in it  Think the pink end is a failing tube?  

Nope.  It's actually incorrect or incomplete wiring or a faulty ballast.  It's been like this since another electrician changed out the ballast about a year ago.  I'll be addressing this as soon as some new ballasts arrive.  When I place a new tube into the fixture, it will start off fully lit, then over about 10 minutes, the end will go pink.  Me thinks not enough juice getting to that end.  Already checked the wires going into the tombstone/socket.    


Crappy Magnatek Ballasts.  I have a bucket full of these that failed with less than 5 years on them.



Here is another brand that I have a bucket full of dead ballasts with less than 5 years on them.  With this brand, either the tubes will strobe rapidly, or will instantly die, or will kill off one side of a fixture.  Name is Howard Industries.  I have 6 more fixtures with these ballasts in them that have failed or one side has failed.  Waiting for a new shipment of Sylvania ballasts to arrive to replace them with. These fixtures are not on all the time and average about 10-20 hours of use a week.  




Combination of faulty Magnatek and Howard Industries that I ran out of bucket space for.


Me having some fun with a late 80s vintage GE G40T12 tube that reached EOL in a standard T12 ballast fixture, however I took it to the next extreme in a T8 equipped fixture <grin> Death by gas burn off and end cap failure!  


Here are some cell phone quality videos I took tonight of me having fun with the EOL GE F40s as well as some shots of that building's closet where I have new and EOL tubes stored.  Click on the photos.

I remember seeing this effect in vintage F40's on vintage fixtures as kid : brightness gradient across the lamp, from full-power end to dim or unlit end

The fixturew were very old and derelict (but still powered), so all lamps and gear were failing originals, so definitely not HF

How is such appearance possible on rapid start ? It is not HF so i dobt it has anything to do with current flowing from 1 end of the lmp to the earthed fixture through capacity between the lamp and the fixture ?

The one end seems to be mercury deficient (it isn't dark, but glow pink, what mean the discharge is missing the green part). It seems the amalgam didn't reach required temperature during the operation, so consume the mercury back after the few months. It may be missing filament supply on RS ballast combined with too low power delivered to the lamp (bad/missing contact)

I wonder if it possible that a HF ballast could be defective and run "half cycle"...basically putting DC to the lamp causing the pink glowing end. My older Sylvania ballasts (they are the old Motorola design) will do this when a lamp electrode fails. The frequency is so high that lamp appears normal brightness while it is actually rectifying.

I wonder if it possible that a HF ballast could be defective and run "half cycle"...basically putting DC to the lamp causing the pink glowing end. My older Sylvania ballasts (they are the old Motorola design) will do this when a lamp electrode fails. The frequency is so high that lamp appears normal brightness while it is actually rectifying.

That would be the case only for NPF ballast with the doubler on the input.

With power factor corrected ballasts the ballast would do it either to both lamps, as for DC they are in fact in series (directly connected on one end, via ballasting coils on the second end), or fore none of them, if it uses separate DC blocking capacitor for each lamp.

Nice pictures Ryan.  In the future, I'd recommend putting the photos in the Gallery.  It's fine use pictures sparingly in forum posts, but when you have a lot of them it tends to become cluttered.  Plus, it is easier to locate specific pictures using the Gallery search than it is to try to find them in the middle of a message board topic.  Thanks.