Stupid Tranny Question

[blearyeyes]

Building a Callosalus and the BOM calls for BC549C Trannies, Tayda has BC549Bs and Mouser states that the C's are obsolete and the BC549CTA might work but they all seem to have the same specs, they all look the same, so why all the confabulation, obscuration and discombobulation with the letters?  Is there an inside scoop on what's up with that?  I have always ignored this in the past but for some reason I am compelled to ask you this stupid tranny question.

Want to avoid any gotchas just in case...

[Clayford]

different HFE buckets. i.e. It was originally hard to keep a semiconductor part in spec. This range is A, this range is B, etc, etc.

The mouser suggested part is a formed and taped lead version according to the page. You should be just fine.
For the record B vs C on this part

Code Select Expand


HFE buckets
type  min  typ  max
  b   200  290  450
  c   420  500  800



[blearyeyes]

Thanks Clayford,
Wish I knew more about transistors but there is so much to learn in electronics it is hard to limit yourself to what is humanly possible.

[blearyeyes]

OK I went back and looked at the Data Sheet again and saw the Classification section. Thanks for the tip.

[Blues Healer]

I have some of the CTAs, and they're fine.
FWIW, if you use sockets, I've found the 'kinked' leads easier to work with -- the legs are already spread to match most board spacing better.