2N vs. PN transistors

[Paul Schreiber]

They are 100% the same thing in 99.99999% of the cases, IF there is a direct
cross to the 2N: ie a PN3904 is the same as a 2N3904. But.....(read on).

The PN means that they are NOT "JAN" tested 100% and hence "cheaper". The
PN was the National/Fairchild 'cheapie' while Motorola has the 'MPS' series
and Texas
Instruments had "TISxxx". Many MiniMoogs used TIS97 parts in the filter.

The history was the plastic molded TO-92 parts were offered before they were
"officially"
given a 2Nxxxx number. JAN (I used to remember what that stood for:
something like
"Joint American/National" it was part of the E.I.A. committee that did all
the RS-xxx specs
like RS-232).

Also, if you want a 2Nxxxx rating you have to publish *everything* about the
part (even the SPICE model!)
and some companies didn't want to do that, ESPECIALLY Motorola!!

Who cares? Because back in the transistor glory days (1967-1977) the PN/MPS
parts were
1/2 the cost of a 2Nxxxx part, EVEN when the plastic TO-92 case was
approved. Even today you can call
a distributor and buy a plastic 2N2222 or a PN2222 and the PN parts is maybe
1 cent less.

IF you were buying ONE MILLION parts a month like many companies did (Tandy)
, that 1 cent meant something.

The fun question we would ask the sales people was: What testing did you
leave out on the PN/MPS/etc part??

BTW: The Moto MPSA series is still a wonderful bunch of parts: MPSA05 and
MPSA92 are 2 favorites.

Paul Schreiber
Synthesis Technology


-----Original Message-----
From: Hcabnivek at aol.com <Hcabnivek at aol.com>
To: synth-diy at mailhost.bpa.nl <synth-diy at mailhost.bpa.nl>
Date: Sunday, June 13, 1999 2:07 PM
Subject: 2N vs. PN transistors


>Can someone tell me what, if any, is the difference between transistors
with
>the prefix 2n and those with the prefix PN  e.g. 2N2222 vs. PN2222 .  Are
>they usually or always substitutable one for the other?
>Thanks,
>Kevin
>