On Thu, 25 Dec 2008 19:00:50 -0500, Sam Goldwasser
put finger to keyboard and composed:

Franc Zabkar writes:

On Thu, 25 Dec 2008 14:28:43 -0000, "N_Cook" put
finger to keyboard and composed:

Sam Goldwasser wrote in message
...
This one was rather strange, at least to me.

One of two horizontally mounted spiral GE CFLs in a semi-enclosed fixture
simply winked out. It's one I had repaired cracked solder joints on a
year
or so ago so I figured time to resolder if the transistors/MOSFETs weren't
toast.

Checked all common suspects for shorts/opens as well as the lamp for
good filaments, no problesm found.

Resoldered some questionable joints - no sign of life.

Then I noticed IT - a dimple near one end of the tube and a resistor
lead could be inserted straight into the inside. A pinpoint on the
inside surface of the glass must have gotten really hot.

How often do you see that?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/

Is the keyphrase "horizontally mounted " and the hole was where the mercury
condensed into a ball ?

If this was a real problem, then wouldn't you expect to see these
kinds of failures in the long, straight, horizontally mounted
fluorescent tubes?

Don't know if it's a real problem, but it was a real failure.

The current density is lower in the fat straight ones but since I have
no idea how this happened, it's hard to even speculate on whether other
types are prone to it.

I'd return the faulty CFL to GE with a comment to the effect that a
lamp that leaks mercury into the household atmosphere is a potentially
serious health hazard. Ask them how long it will be before you will be
able to tell whether the toxins have poisoned your liver. I guarantee
you'll get a box full of free replacements in a matter of days. :-)

- Franc Zabkar
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