Light fixture

Does this fixture share a branch circuit that has anything such as an aquarium heater on the same circuit ?? Anything that would cycle on and off by itself ? refrigerator, freezer, laser printer, waterbed heater, etc

Is it on a dimmer switch ??

As far as a branch, I dont believe it is on anything that would cause a disturbance. I don't believe it is a dimmer switch either.

Not a photosensor. Just a plain old fixture.

If you have a photo cell that turns the light on they will pulse when turning on at dusk and off in the morning but this will burn out the electronics in the bulb base and it will fail in a couple of months. That's when I read the instructions on the second bulb. ;-(

Can you describe the "pulse" please? How frequently does it occur, how long do the "dim" periods last, etc.

Have you tried a regular incandescent bulb in that fixture recently? If so, does it light OK?

Jeff

As others have indicated, any kind of dimmer, photocell or other than a standard switch in the circuit could cause the flickering problem. CFLs may also flicker when cold. However, that flicker will quickly disappear as the lamp warms up especially if the lamp is in an enclosed fixture.

TKM

It is in a bottom open fixture and the incandescent lights up fine.

Correction! The incandescent does not light either. Time for a new fixture!

Or maybe just a new socket?

Jeff

My experience with CF bulbs is they do not always screw in as tightly or completely as regular bulbs for whatever reason. I would first assume that the bulb is not making solid contact with socket. Grab the porcelain base of the bulb and turn a bit tighter. Grabbing by bulb glass is unwise since the bulbs do break readily.