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Transistor identification?

Started by DaveC September 5, 2015
Help with identifying a TO-92 transistor?(at least I think it’s a 
transistor…)

Pretty vanilla-looking with National Semi logo. Marked:

NS 444
ST
13903

(The “NS” is the logo.)

Not enough 4’s to make up a standard 2N number, and 13903 looks like a date 
code?

Ideas?

Thanks,

> Help with identifying a TO-92 transistor?
A photo: http://i.imgur.com/z78xG5D.jpg
On Saturday, 5 September 2015 21:28:49 UTC+1, DaveC  wrote:

> Help with identifying a TO-92 transistor?(at least I think it's a > transistor...) > > Pretty vanilla-looking with National Semi logo. Marked: > > NS 444 > ST > 13903 > > (The "NS" is the logo.) > > Not enough 4's to make up a standard 2N number, and 13903 looks like a date > code? > > Ideas? > > Thanks,
Why does it matter? It normally doesn't. NT
On Sat, 05 Sep 2015 14:18:56 -0700, DaveC <not@home.cow> Gave us:

>> Help with identifying a TO-92 transistor? > >A photo: > >http://i.imgur.com/z78xG5D.jpg
Put one of these in its place... http://www.edn.com/design/test-and-measurement/4437360/How-to-measure-the-world-s-fastest-power-switch Just kidding, but hey... check out the report anyway...
How's it measure?

(Or if it's dead, is there another one probably working that you can test?)

Tim

-- 
Seven Transistor Labs
Electrical Engineering Consultation
Website: http://seventransistorlabs.com

"DaveC" <not@home.cow> wrote in message 
news:0001HW.1B9B87FD00098A2611E4F83CF@news.eternal-september.org...
> Help with identifying a TO-92 transistor?(at least I think it&rsquo;s a > transistor&hellip;) > > Pretty vanilla-looking with National Semi logo. Marked: > > NS 444 > ST > 13903 > > (The &ldquo;NS&rdquo; is the logo.) > > Not enough 4&rsquo;s to make up a standard 2N number, and 13903 looks like a > date > code? > > Ideas? > > Thanks, >
> How's it measure? > > (Or if it's dead, is there another one probably working that you can test?) > > Tim
Dead. Other with identical markings measure as NPN. What else to determine from measurements? Thanks.
On 09/05/2015 2:18 PM, Dave C wrote:
>> Help with identifying a TO-92 transistor? > > A photo: > > http://i.imgur.com/z78xG5D.jpg >
Looks like a house number - made by National of course. House numbers can sometimes cross reference to other parts if you can find a master list. How made the item in question. John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."
On Sunday, 6 September 2015 14:40:22 UTC+10, DaveC  wrote:
> > How's it measure? > > > > (Or if it's dead, is there another one probably working that you can test?) > > > > Tim > > Dead. Other with identical markings measure as NPN. What else to determine > from measurements?
Current gain. If it isn't high - in the several hundreds - it might be something interesting. Gain-bandwidth product. If it were high - 5GHz or better - and I don't recall Nat. Semi. ever doing anything that interesting - it could mean a thin base and a 2V base-emitter breakdown voltage. -- Bill Sloman, Sydney
> [Who] made the item in question. [?] > John :-#)#
An American offset printing equipment company. It&rsquo;s a paper/envelope feeder for a small offset presses. Extinct company. I can say that the bandwidth requirement of the circuit is very small&mdash;DC-10 KHz&mdash;and low current. Don&rsquo;t know about gain. Thanks.
On 05/09/2015 21:28, DaveC wrote:
> Help with identifying a TO-92 transistor?(at least I think it&rsquo;s a > transistor&hellip;) > > Pretty vanilla-looking with National Semi logo. Marked: > > NS 444 > ST > 13903 > > (The &ldquo;NS&rdquo; is the logo.) > > Not enough 4&rsquo;s to make up a standard 2N number, and 13903 looks like a date > code? > > Ideas? > > Thanks, >
Or maker ST and date code for 1994 or 2004 or whatever goes with NS as plant/batch code for a particular decade