[sdiy] 2N3808 dual pnp

[René Schmitz]

Hi Ruud and List,

first you need to determine which one is the base. If your scope has a
curve tracer this is fairly easy, just try all possible combinations.
Compare the traces to a known transistor to see what the curves look
like. The connections of BE and BC look like a diode, because the
transistor is made up internally of two diode junctions. The polarity of
the junctions tell you whether it is a NPN (base is Anode) or PNP (base
is Kathode). You can also determine this with a DVM which has a diode
tester, but that doesn't tell you anything about which is the collector
and emitter. (You'll mostly find that the emitter base junction has a
relatively low breakdown voltage, which you can see on the trace.)

Cheers,
  René

Rude 66 wrote:
> a related question:
> 
> is there an easy way to determine if a transistor is pnp or npn? i
> have a whole bunch of recycled ones, but can't find any info about
> this..
> 
> thanks!
> 
> ruud
> 
-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159