[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Core memory

At 11:18 AM 3/12/96, Steve VanDevender wrote:
>Timothy van der Linden writes:
> > > > Why doesn't the magnetic field in the ferrite core degrade? (I
>assume the
> > > > ferrite has some resistance.)
> > >
> > >Have you ever known other magnets to degrade?  Once magnetized, a
> > >material won't demagnetize unless exposed to heat above its Curie point
> > >or another sufficiently strong magnetic field.
> >
> > Oh, now I understand, you create a permanent magnetic field just like
> > magnetic discs and tapes. (I though you created a current in the core) So in
> > fact the cores don't need to be closed completely.
> >
> > Tim
>
>The core is in essence just a lump of magnetizable material; they were
>generally made toroidal because it was easiest to string them that way.
>
>There were some designs for magnetic memory that didn't use cores, but
>(if I recall correctly) used spots of magnetic material sandwiched
>between two layers of parallel conductors.  And even more exotic memory
>hardware has existed -- ever heard of mecury delay lines?  Williams
>tubes?

Magnetic bubbles?


----------------------------------------------------------------------

Kelly Starks                       Internet: kgstar@most.fw.hac.com
Sr. Systems Engineer
Magnavox Electronic Systems Company
(Magnavox URL: http://www.fw.hac.com/external.html)

----------------------------------------------------------------------