Date: Mon, 05 Apr 1999 17:26:31 -0400

Author: Machele Bailey

Subject: Re: aliasing demos

Post:

Just as a person who uses an alias to appear to be someone else, a sine wave will
appear to be a different frequency if aliasing is involved.

Chele

Steve Wonnell wrote:

> >From Webster's New Collegiate Dictionary, 2nd ed.:
>
> alias, adv. In full: a'lias dic'tus. Otherwise; otherwise called.
> --n.; pl. aliases. Another name; an assumed name.
>
> Hi Kelly & Chele,
> I understand the phenomenon that Chele describes below, but I don't
> understand why it's called aliasing. Can you describe the connection?
>
> Steve W.
>
> On Mon, 5 Apr 1999, Machele Bailey wrote:
>
> > Date: Mon, 05 Apr 1999 16:10:45 -0400
> > From: Machele Bailey
> > Reply-To: tap-l@listproc.appstate.edu
> > To: tap-l@listproc.appstate.edu
> > Subject: Re: aliasing demos
> >
> > Aliasing comes about when the sampling rate is too slow for the waveform. Let's
> > say you have a pretty sine wave input, but your sampling is set so that you only
> > get a point at each crest....the output would be a flat line! You can also think
> > of it as a strobe effect....if the frequency of the strobe doesn't match the
> > dripping water or fan rotation, then you "see" a slower or faster motion than
> > what's really there.
> >
> > Chele
> >
> > Gerald Zani wrote:
> >
> > > Am I correct to think that "aliasing" is the fancy way to say describe a beat
> > > phenomenon? Or is there a difference?JZ
> > >
> > > you wrote:
> > > >Help! One of our faculty has asked me for some help in identifying
> > > >aliasing demos. We already do a couple with a fan and strobe. The faculty
> > > >would now like to do an aliasing demo with sound. Any suggestions?
> > > >Thanks! Kelly
> >
> >
> >
> > --
> >
> > ~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~
> > Work like you don't need money,
> > love like you've never been hurt,
> > dance like no one's watching;
> > For happiness is a journey,
> > not a destination.
> > **********************
> > Machele Bailey
> > Lab Manager
> > Physics Department
> > Wake Forest University
> > (336) 758-5532
> > ~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~
> >
> >
>
> ***********************************************************************
> Steven K. Wonnell
> Physics and Astronomy Department E-Mail: wonnell@pha.jhu.edu
> Johns Hopkins University Phone: (410) 516-4696
> 3400 N. Charles Street Fax: (410) 516-7239
> Baltimore, MD 21218-2686 Office: 403 Bloomberg (x0544)
> ***********************************************************************



--

~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~
Work like you don't need money,
love like you've never been hurt,
dance like no one's watching;
For happiness is a journey,
not a destination.
**********************
Machele Bailey
Lab Manager
Physics Department
Wake Forest University
(336) 758-5532
~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~@~~~

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