Chuck Harris wrote:

Robert Baer wrote:

Definitely, mechanical stress seems to enhance or aggrivate the
migration of the solder.
Monitors exhibit similar problems; one or more colors get
intermittent and / or go out.
One then must re-solder the CRT socket to the PCB.
The mechanical stress comes from the sponge in the back of the case
that presses on the metal cage around that PCB.
I have fixed dozens of monitors that way, some 2 or three times.
The one i have was bought 12-15 years ago and fixed 3 times so far.
I have called it electomigration, because of the metal flow patterns
with regard to presumed current flow in each trace.


The problem is much simpler than that. The holes in the board are
too big, and as a result, the solder is required to bridge a large
gap. Solder has next to no ability to withstand repeated flexing, so
the relatively thin solder bridge flexes and cracks.

The answer is simple all joints should be good mechanical joints. The
socket will last longer if you bend its pins outward so that they are
leaning
against the pad before you apply solder.

-Chuck
I do agree that good mechanical connections make for reliable
connections.
But.
On all of the monitors i have fixed so far, the CRT socket pins were
bent over and were touching / flat against the traces.
Furthermore, the original soldering was "blobbed" on; ie very thick
(and crappy looking).
All of that does tend to reduce and spread out the mechanical stresses.
My fixes are to remove all of the solder and replace it with a "thin"
workmanship-like hot soldering job. The fixes seem to last about as
long as the original.