Meat Plow wrote:
On Mon, 1 Dec 2008 18:56:38 -0000, "ian field"
wrote:

"Meat Plow" wrote in message
...
On Mon, 1 Dec 2008 17:53:16 -0000, "ian field"
wrote:

wrote in message
...
I only two of them in my house.One in my kitchen and the other one in my
bathroom, I never turn them off.Just now I was in my kitchen getting me
a ''cold one''.That flourscent light bulb blipped a couple of times.What
does that suppose to mean?
cuhulin

Maybe a "brown-out" on the power line?

The one I leave on 24/7 usually conspires to fail when I'm out. Common
failure modes are the tube or the mains in reservoir electrolytic,
typically
they start flickering or just go "phutt".

Back in 2003 I saw a 13 watt Osram CFL end its life in bursts of
sparks and smoke through a hole melted in the side of the ballast
container. I called Sylvania/Osram and they offered a replacement free
of charge. I told them no thanks I prefer to not have my home burn
down if another one of these failed while I wasn't present to
disconnect its power source. That scared me away from CFLs for a long
time.
The only one I ever saw do that was one I'd fitted bigger transistors in an
attempt to use it as an electronic ballast in a 6' strip light - it even
worked for a few days before blowing up.


I used to love to experiment like that.

Some times it just "feels so good" to let the smoke out.

A few months ago, our shop was shipped some incorrect Bosch automotive
relays we use to honk the horn from the LMR radio (crew page).

The problem was that these had an internal "back EMF" snubber diode
across the coil. That would be no problem if plugged into a prewired
socket, but we wire them manually with spade lugs and often in poor
light where you couldn't see the diode polarity-to-lug markings on the
schematic molded into the black plastic . Get the coil wires
backwards... blow the switch transistors in the radio!

The fast fix was to hook up a 20A bench supply to the relay coil
terminals so the diode was forward biased and watch the current jump to
20amps for a second as the diode blew out... no longer a problem. Only
bad part was the smoke couldn't get out as the relay is sealed.