Guess what light this is...

[joe_347V]

Westinghouse OV-25 IB "Silverliner" aka Flat Bottom

Ballasts and starters for this type of lamp haven't been made for a couple decades but replacement lamps are still made but by only one company.

[GEsoftwhite100watts]

I meant 34w energy saver florescent tubes
I'm guessing F90T17?
Used to light stores a lot and sometimes even homewowners use these 8 foot fixtures but now the're becoming less common because T8 is taking over.

[joe_347V]

Yep F90T17, I guess F96T12?

Most common fluorescent lamp before the 1990s.

[GEsoftwhite100watts]

F40T12
Underdrives lamps

[A_lights]

Low power factor ballast

Company bought out by Philips

[Mike]

Advance Transformer Co.

BTW, i think F90T17 starters are still made, though they're very hard to find. I've seen a site online that sells them...

Lamps typically rectify at EOL with this type of fluorescent ballast...

[GEsoftwhite100watts]

Either slimlines or NPF shoplights

[Mike]

Nope i was referring to preheat chokes. With rapid start, the circut opens up with a rectifying lamp to save the ballast from overheating and spilling tar, etc. I'm not sure about F40T12 preheaters or potted F20T12 ballasts, but the bare chokes don't have any mechanism to open the circut.

Is thic light is working properly, it SHOULD cycle. You can find them all over the city.

[GEsoftwhite100watts]

high pressure sodium
Start dim in the middle in freezing temperatures

[joe_347V]

Alto or other low mercury fluorescent lamps.

Lasts a long time but can only be used base down or sideways.

[GEsoftwhite100watts]

3 way bulbs?
You should always remove bad tubes from these lights if you can to save the ballast and insane flashing/strobing/flickering/buzzing

[Mike]

high pressure sodium
Start dim in the middle in freezing temperatures

No, a traffic light. HPS lamps should not cycle if they work properly. If it's cycling, it's malfunctioning.

. . .

preheat fluorescent.

. . .

This style ballast provides the "cleanest" energy (meaning keeps voltag consistant, therefore ideal for areas with inconsistant line voltage) to the lamp but suffers from high ballast losses in return.

[A_lights]

Nope i was referring to preheat chokes. With rapid start, the circuit opens up with a rectifying lamp to save the ballast from overheating and spilling tar, etc. I'm not sure about F40T12 preheaters or potted F20T12 ballasts, but the bare chokes don't have any mechanism to open the circuit.

that would be the capacitor blocking the DC current from "back-feeding" though the ballast coils

slimline ballasts have a problem when lamp fails on the Lag side, the capacitor is not present there and a rectifying lamp will cause DC current to backflow through the ballast and will overheat but thermal protection usually saves it a few times until it frys itself after a few EOL lamps doing this ...lead side lamp looses vacuum quick and no damage done there
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Guessing

CWA ballast

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Mercury starved lamps are almost usually this brand 

[GEsoftwhite100watts]

Philips
Starts with pink/purple flashes then shifts to a dim blue green then warms up to full brightness in about 5-7 minutes.

[A_lights]

Sounds like a coated or clear MV seen clear ones do the flashing pink near the electrodes


A light that is pure white and blinks rapidly. .some are adjustable