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Posted to 24hoursupport.helpdesk,sci.electronics.repair
Jeff Liebermann Jeff Liebermann is offline
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Default motherboards power socket reapir on laptop

On Sat, 14 Jun 2008 04:00:40 -0700 (PDT), wrote:

Hi, I had a loose power socket and superglued it and that lasted just
fine for a few months. Then it went out beyond
an ability to glue it again, but still have a occasional power
connection when moving it.


Superglue doesn't work with the plastic sockets. Use 24 hr epoxy (not
the 15 minute crap), and let it harden for a while. Obviously, keep
it away from the metal contacts.

I pulled out the motherboard and the solder
on the bottom side of the board where the socket connects, the solder
was burnt away and brittle.


Ok, it's arcing. What happened is that the wiggling of the socket
created an annular ring around the solder pad. In some positions,
there was enough of a gap, and enough current, to create a miniature
arc welder. That sometimes destroys the board. See my photos at:
http://802.11junk.com/jeffl/pics/HP-laptop/slides/Fried_power_plug.html
Sorry about the lousy focus job.

The problem is that the carbonized PCB material mixes with the solder
when you try to resolder the connection. All you get is a mess. Take
a sharp pin, awl, wire brush, screwdriver, scraper, whatever, and get
as much of the carbon off as possible. Then solder.

I'm not much of a solderer, just have a cheap soldering iron with a
large tip.


You need an expensive iron with a small tip. Large tips are fine, but
you have to work fast or you'll torch the connection. There are
plenty of cheap, thermostatically controlled irons, with transmormers
in the stand, thermistors in the iron, replaceable tips, and
temperature controls. Consider it a good (lifetime) investment.

Is there a pretty much common method to repair this, I was
thinking of dropping a drop of solder where the solder failed instead
of finding somebody to repair it. Then putting the laptop back
together and see if it works and do a re-superglue of the offending
loose socket.


Glue it while it's open. Better yet, get a replacement connector.
They're all over eBay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=110224164976

Thanks for any tips or suggestions. Tools needed, over my head in my
abilities?


Find someone who can solder to do this. The practice with a decent
soldering iron and some junk electronics. When you figure out which
end of the iron to grab, you're ready to attack the laptop.

Incidentally, I'm impressed that you're able to take it apart. That's
generally not an easy thing to do.

It's a compaq presario 1692


Thanks. You should have mentioned that first.

--
Jeff Liebermann

150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558