On Wed, 21 Jan 2004 22:21:31 -0800, "Tim Wescott"
wrote:

I wouldn't assume that just because your test equipment comes to you broken
is a result of tantalum caps -- perhaps your sample is skewed by buying at
hamfests instead of burgling active technology companies? Maybe if you only
acquired your home entertainment equipment from dumpsters you'd conclude
that aluminum electrolytics are bad?

I recently escaped from a company that does aero (but not space) systems.
They get mounted on aircraft and are expected to survive being shipped in an
unpressurized cargo hold at 50000 feet. At that altitude a wet aluminum
electrolytic will dry out, but a tantalum will be fine. There are even
wet-slug tantalums for high-altitude applications that will not dry out at
these altitudes.


Wet-slug tants are expensive (do they still have silver cases?) but
don't blow up like the dry ones. The dry slugs coat the sintered
tantalum (fuel) with MnO2 (oxidizer).


The problems with tantalum are their fragility (we've had exploding caps on
our boards, with one manufacturer's part being fine and another being
horrid), cost, and the relative scarcity of tantalum.

This is really erratic. One spool of tants will be bombs, another
can't be made to fail by deliberate abuse.

John