I have some of those myself...they are actually made in China!!!!! Early days made in China stuff...but nerveless they were pretty good! I have one of those ballast and it dated to 1992!
Cool. Both were laying in the "light bulb cabinet" in my great-grandparents' house. My great aunt Kathy now lives there and she let me have those and she said I can have the F90T17 fixture in the garage any time i want to take it. That won't be for a while though... She was going to let me have some F20T12 blackenders too (I forget the brand, but it wasn't GE, Phillips, Westinghouse, or Sylvania) but i said she better keep them for the F20T12 preheaters in the basement since the older fixtures don't work well with the newer junkier lamps. There are I think more than 4 blackender F20T12 lamps, all cool white. I've considered trading my electronic fluorescents for the preheaters, but I'm not sure yet...
Ummm Ian, I am pretty surprised you didn't know, those were the CFL before spirals came out! Those were found in any fixtures like table lamps, any fixtures that actually allowed this to fit, its like those spirals except in magnetic ballast. In the old days they didn't have technology to make small electronic ballasts and make spirals easily, so those were the stuff we used back in the 80s and early 90s. The spirals did not come out until 1997. Before the spirals, those were the shapes of the CFL! Some were too big to fit in a smaller fixture. Some were way too heavy to go in a tall floor lamp....but they were DARN more reliable than the today's junk spirals! Those ACTUALLY lasted 7 years, and some even MORE over lasting the rated hours! Good ol' CFL back in the old days before SPIRALS!!!
There were more lamps that had replaceable fluorescent bulb from the ballast bases...but the companies started making built in unremoveable ones more, probably just to make more money or something. I really wish they would continue to make removable tubes from the ballast base...
Suggestion, start looking at bulbs and stuff and not only focus on streetlights, you will learn a LOT more and they will be very interesting!
SYLVANIA GTE
F13DTT/27K
06 MADE IN USA
I also have a GTE Sylvania adapter too, not sure on date though.
There were more lamps that had replaceable fluorescent bulb from the ballast bases...but the companies started making built in unremoveable ones more, probably just to make more money or something. I really wish they would continue to make removable tubes from the ballast base...
Suggestion, start looking at bulbs and stuff and not only focus on streetlights, you will learn a LOT more and they will be very interesting!