[time-nuts] 5MHz ocxo- Opening Solder sealed cans

[Paul Flinders]

On 27/07/12 03:17, Tom Miller wrote:
> I agree with Ron. Clean the board up real good then do an inspection. 
> With a microscope if you can get your hands on one. Look for cracked 
> SMT parts. The high heat from the oven could very well stress the 
> parts causing a failure. Flux the board up and hit all the connections 
> with a small iron. When you melt the solder on each end of a part, if 
> one is broken, it will then show up.
Thanks for the tips.

On further reflection I think that the foam probably has disintegrated 
over time (mostly). The pattern of what is melted/stuck to components is 
wrong for an exogenous heat source. I might have to play around with 
solvents as IPA didn't have much effect on the really stuck down stuff.

I agree it's likely to be a dry joint or cracked SM part so the plan of 
a thorough clean and visual inspection is a good one - I don't have 
access to a microscope but do have a couple of decent hand lenses. I 
suspect careful use of the heat gun and freezer spray will help as well.

I'm going to be away for a week so will pick this up again when I get 
back. I'll update the list with any progress.