[sdiy] transistor matching circuit

[Jim Thompson]

Hello Group,
Always looking to help, I have access to the expensive Tektronix curve 
tracer linked below if anyone needs transistor data. It's awesome and will 
tell you anything you need to know while testing any semiconductor up to 
2000 volts.

http://www.metrictest.com/product_info.jsp?mfgmdl=TEK%20370

Jim

>From: Peter Grenader <peter at buzzclick-music.com>
>To: <xyzzy at sysabend.org>
>CC: SDIY <synth-diy at dropmix.xs4all.nl>
>Subject: Re: [sdiy] transistor matching circuit
>Date: Tue, 14 Dec 2004 15:53:49 -0800
>
>As lame as this definition may be, a curve tracer plots the voltage/current
>curve of anything plugged into it's test socket.  It usually involves with
>it a scope in the X/Y mode, but many have built in tubes of their own.
>Depending on the tracer's sophistication, one can arrange the DUT (device
>under test) to a plethora of load configurations giving way  to 'see' many
>different parametric specs on the tube.
>
>For instance, if you put  5 volt zener in there and raise the test voltage
>slowly you'll see basically a straight line which will elbow sharply at
>somewhere around 5.1 volts indicating it's breakdown voltage.  While one
>would not need a tracer to test a diode's limit, there are many parameters
>that these things will come in handy for - transistor beta being one of
>those as it's not linear.
>
>We use to use them to sample test diodes and trannies at incoming
>inspection, which the guys there hated doing because there was no handler
>nor automated test involved.  You 'd have to set the machine up, insert the
>correct adaptor and basically test them one at a time by hand, inserting 
>and
>reinserting and raising the voltage for each then making a visual
>determination if the thing was to spec or not - their hesitancy was
>understandable.
>
>They are way cool machines though.
>
>- P
>
>Tom Arnold wrote:
>
> > On Tue, Dec 14, 2004 at 03:17:26PM -0800, Peter Grenader wrote:
> >> There a few of curve tracer scope fixtures on ebay right now going 
>pretty
> >> cheaply - under $50. The full blown tek's with the tube displays are 
>still
> >> pricey at about $500
> >
> > Pardon me for being dense, but what exactly is a curve tracer?
> > I see them surplus all the time for cheap but never paid much attention 
>to
> > them.
>