I'm attempting to diagnose some strange electronics behavior. And it seems
to be coming down to this question:

What types of components have failure modes that are temperature independent
and are self healing over a time period of days?

--
Paul Hovnanian
------------------------------------------------------------------
Don't anthropomorphize computers. They hate that.

"Paul Hovnanian PITA "

I'm attempting to diagnose some strange electronics behavior. And it seems
to be coming down to this question:

What types of components have failure modes that are temperature
independent
and are self healing over a time period of days?


** You are like the blind man who grabbed elephant by the tail and said:

" Ah - an elephant is just like a snake !!! "

Most intermittent faults behave like you describe if viewed over an
INSUFFICIENT time scale.

Think about it a bit harder.



..... Phil

On Friday, April 27, 2012 12:44:09 PM UTC-7, Paul Hovnanian P.E. wrote:
I'm attempting to diagnose some strange electronics behavior. And it seems
to be coming down to this question:

What types of components have failure modes that are temperature independent
and are self healing over a time period of days?

--
Paul Hovnanian
------------------------------------------------------------------
Don't anthropomorphize computers. They hate that.

Well, a common problem that is moderately temperature independent and takes hours to days to reappear is cracking solder connections. If the unit or PCB is disturbed, the cracked joint will remake contact and stay good for as long as it takes for the rubbed connection to form an insulating film at the contact point.
I am not sure that this is what you asked, though. Do you mean that the unit fails, and after a few days it works again? In that case, I would look at electrolytic capacitors.

Neil S.

The only genuinely "self-healing" components I know of are Mylar capacitors.
The dielectric can be pinhole-punctured by line transients, then gradually
recover. (There might be other dielectrics with this property.)

William Sommerwerck wrote:
The only genuinely "self-healing" components I know of are Mylar capacitors.
The dielectric can be pinhole-punctured by line transients, then gradually
recover. (There might be other dielectrics with this property.)

more specifically it would be metallized capacitors with no foil in them.
A transient will puncture the dielectric and then the metallized layer
aound it burns up and there's nothing left to conduct in that area, so the
short clears out. It's pretty cool.

You loose a bit of capacitance each time this happens as the surface are
of the places decreases each time some burns away, but for most stuff it
doesn't really matter.