What can I use these transistors for and what are they?

[boogietube]

Just picked up some nos trannys
Wanted to know about them and what I might use them for:
2SA49
2SC28 1
2SA12
2SA234
2SA468
S2B175
2SB348
2SA104
2SB136
2SA52
2SB75
2SB172
2SB136
2SA53
Thanks for the help!

[brett]

A few clues:
2SA and 2SB are PNP
2SC and 2SD are NPN
2SK - fets

2sb175 - ge PNP - a really great transistor for a fuzzface
2sb348 - is that 348 or 248?  IIRC the 248 is also very handy

But anyway, I suggest that first you test them (with a multimeter) to work out which are NPN and which are PNP.  Google the method.
Then build the tester at geofex.com and determine the true hFE and leakage.  Devices with les than 250 uA of leakage and hFE of 50 to 200 are very useful.

Generally, you can expect only about half of a batch (unsorted) to be good.  Fortunately, these Japanese transistors are better (often MUCH better) than batches from other sources.
Good luck.

[Rob Strand]

There's heaps of site with info on these type transistors.  Most of it isn't that useful.

For the germaniums measure the leakage and gain then, if the parameters are OK, use them in just about any ckt requiring a Ge transistor.

[Mark Hammer]

Just picked up some nos trannys
Wanted to know about them and what I might use them for:
2SA49
2SC28 1
2SA12
2SA234
2SA468
S2B175
2SB348
2SA104
2SB136
2SA52
2SB75
2SB172
2SB136
2SA53
Thanks for the help!

Looks like somebody paid a trip down to A.D.D. Electronics!   (A local surplus electronics place that has an ever-shrinking pile of shrink-wrapped Japanese Ge tranny "variety packs", 6 to a card for a buck).  I thought I had snagged all the 2SB172s already!

Note that all those transistors will need to be checked for leakage.  They may be NOS but that doesn't mean they're GOS! (good old stock)