At 08:38 AM 15/06/2002 -0700, you wrote:
>Brendan Moran <annirak@BIGFOOT.COM> wrote:
> > Now Here's the real question:  if you have that bell curve, what do you do
> > with all the -ve resistance resistors?
> >
> > Problem comes, though, when your resistor has to have 4 pins (supply leads)
> > to operate at the intended resistance ;)
>
>We used to joke about that in college. A true "negative resistor" would
>extract heat from the environment and produce a current flow. You'd have to
>be careful not to let the leads short together, or a massive current would
>flow and its temperature would quickly drop to absolute zero. You could get
>some serious "freezer burns" that way :-).
>
>Of course, there are devices that exhibit negative resistance, in the sense
>that dV/dI is a negative value over certain parts of their operational
>curves. They all still dissipate power in an absolute sense (V/I > 0),
>however.

Yeah, an opamp and a few resistors would do it, that's what I meant by the
4-pin resistor.

--Brendan

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