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ian field ian field is offline
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Default Strange shrunken capacitor(?)


wrote in message
oups.com...
On Jun 12, 10:04 am, "ian field" wrote:
"w9gb" wrote in message

. ..





"Yattaro" wrote in message
. net...
I have an old Gateway EV700 monitor which shuts down after a few
minutes
of
use. It sometimes sort of flashes the screen as if maybe it's trying
to
start
back up, but is never able to on its own. It will come back on for a
few
seconds if power cycled, but will then shut down again.


After it's been off for awhile it will come back on and last a few
more
minutes, but then exhibits the above problems again. When it shuts
down,
it
has a sort of rainbow swirl pattern in the center of the screen.


I opened it up to see if there was anything obviously wrong, and saw
what
looks like a capacitor which has been twisted and shrunken, but I'll
admit
that my knowledge is limited enough that it could be something else
entirely.


Here are some pictures. The white goo on the side is just glue, it
didn't
come from inside the object. I didn't see any obvious signs of leakage
or
damage, but this thing certainly looks unnatural.


http://tinyurl.com/2ysl3r
http://tinyurl.com/ytxby8
http://tinyurl.com/2gbe8v


Any idea what this is, if it's bad, and if replacing it might solve
the
shutdown problem?


Thanks for any info anyone can provide.


1. The "white goo" appears to be hot glue use to hold the component
(possibly during wave soldering step)


2. This circuit board has silk-screened legends, such as C102, L302,
etc.
The first character used to identify this component will tell you what
it
is:
"C" - capacitor, "L" - inductor


3. The component appears to have a polarity stripe, like electrolytic
capacitors.


4. IF this is an electrolytic capacitor -- I would replace it based
upon
it physical condition -- but you would need the correct value and
voltage
rating!
From your photos, really can not tell -- no value markings other than
the
marking of: LO5G


Its definitely an inductor - quite likely a linearity coil (polarising
stripe is an obvious clue) close examination may reveal that the ferrite
bobbin has an extra bit glued on the end opposite the leadout wires, this
will be magnetic which is easily confirmed by offering it the tip of a
screwdriver.

Mark the base of the bobbin as per the polarising stripe and peel off the
shrink wrap to inspect the winding for heat damage.

If the part is knackered it will be practically impossible to order a
replacement - go down the dump and claim a monitor of similar size & spec
to
salvage the part from, but try it first - you may get lucky.- Hide quoted
text -

- Show quoted text -


From the part number, it looks like a 0.05uH ferrite-core inductor.

(L05G).

This should be a start, if nothing else.

http://jql.manufacturer.globalsource...r-Inductor.htm

Peter Wieck
Wyncote, PA


For the value of a CRT display these days its hardly worth the effort of
what I suggested, let alone what's involved ordering a one-off part from
China!