Greg Mayman wrote in a message to Roy J. Tellason:

 -=> Roy J. Tellason said to Greg Mayman
 -=> about "*BIG* TRANSISTORS" on 01-08-04  04:06.....

 RJT> It's not like you're bumping into these parts every day, though...

 GM> Yeah. The only devices I have like that are some SCRs that I've put
 GM> away safely for some project, darned if I know where...

 RJT> Yeah,  I'd be a bit disappointed if the gain were less than 20.   :-)

 GM> I was once using some TO3 power transistors that dropped down to a
 GM> gain of 5 worst case at maximum current/minimum voltage. And of
 GM> course that is the combination you ARE likely to get as you push
 GM> them towards saturation.

I've seen that on some data sheets.  I also remember some germanium parts
being particularly pitiful when it came to their specs.  It's amazing they
even bothered to sell such stuff.  :-)

 GM> Fortunately the ones I tested were all above about 10. But you have
 GM> to design for worst case replacements, especially when you're 
 GM> looking at a run of ten or more and a projected life of several 
 GM> years.

Yep.

 GM> I rather think that was one project that I eventually abandoned. 

I would tend to go toward a higher-rated part that wouldn't be pushed so
close to saturation,  but then I don't tend to try and operate much stuff
near its ratings anyway,  preferring to over-spec stuff when I can.  I
guess this is pretty different from a manufacturer's typical perspective...
 :-)

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