In article , Trevor Wilson
wrote:


**Yes and, no. IME, low power, metal can devices demonstrate superior
long term reliability to pre-1980-ish plastic devices. That said, modern
plastic devices appear to provide excellent long term reliability as
well.

The key word, though, is 'can' sorry for the pun!. I've known more than
one 'metal can' transistor that were unreliable for various reasons. So as
with types using other packaging it all comes down to how well the
individual devices were made.

In one case Oops, another pun WRT higher power devices I recall a TO3
device that exploded when powered up at low levels and the top hit part of
the wood around the bench so hard that it embossed the maker's name there.
Turned out to be a batch with water vapour inside the can. More common was,
it seems, simply poor contacts so that the device came free of the
metalwork.

Slainte,

Jim

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