Searching \ for 'MM5437 Digtal Noise Source' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: techref.massmind.org/techref/index.htm?key=mm5437+digtal+noise
Search entire site for: 'MM5437 Digtal Noise Source'.

Truncated match.
PICList Thread
'MM5437 Digtal Noise Source'
1997\02\24@145529 by D. R. Chicotel

flavicon
face
I want to use a PIC to duplicate what a MM5437 Digital Noise Source does.
The MM5437 is no longer available.  I suspect that I can just create random
numbers on PORT B and amplify one of the PORT B pins using a LM386 connected
to a speaker.  This should give the white noise I am looking for.  Does
anyone have any ideas about why this will or will not work?  If anyone has
done something similar, let me know so I can save some time and effort.

1997\02\24@203818 by John Payson

picon face
> I want to use a PIC to duplicate what a MM5437 Digital Noise Source does.
> The MM5437 is no longer available.  I suspect that I can just create random
> numbers on PORT B and amplify one of the PORT B pins using a LM386 connected
> to a speaker.  This should give the white noise I am looking for.  Does
> anyone have any ideas about why this will or will not work?  If anyone has
> done something similar, let me know so I can save some time and effort.

Well.... it all depends what you want the noise for.  If you are trying to
just create a novelty noisemaker, this approach is just fine.  If, however,
you are trying to create a sound with particular spectral properties (for
measuring room accoustics, for example) you will need to be careful to
ensure that your output is not distorted and that your "random" function
has the required properties.  Also, if you want good white noise you should
make a resistor-ladder DAC and modulate that.  Otherwise your output will
be top-heavy.

1997\02\24@233020 by tjaart

flavicon
face
D. R. Chicotel wrote:
>
> I want to use a PIC to duplicate what a MM5437 Digital Noise Source does.
> The MM5437 is no longer available.  I suspect that I can just create random
> numbers on PORT B and amplify one of the PORT B pins using a LM386 connected
> to a speaker.  This should give the white noise I am looking for.  Does
> anyone have any ideas about why this will or will not work?  If anyone has
> done something similar, let me know so I can save some time and effort.

You don't need a PIC. A shifht register with XOR feedback will give you
very
good PRN (pseudo random noise)
--
Friendly Regards

Tjaart van der Walt
spam_OUTtjaartTakeThisOuTspamwasp.co.za
_____________________________________________________________
| Another sun-deprived R&D Engineer slaving away in a dungeon |
|             ASP International  http://wasp.co.za            |
|             GSM and GPS value-added applications            |
|  Voice : +27-(0)11-622-8686   |   Fax : +27-(0)11-622-8686  |
|_____________________________________________________________|

1997\02\25@225748 by Martin J. Maney

flavicon
face
On Mon, 24 Feb 1997, D. R. Chicotel wrote:

> I want to use a PIC to duplicate what a MM5437 Digital Noise Source does.
> The MM5437 is no longer available.  I suspect that I can just create random
> numbers on PORT B and amplify one of the PORT B pins using a LM386 connected
> to a speaker.  This should give the white noise I am looking for.  Does

Heck, you can probbaly do better if you work at it.  Unless I'm mixing the
5437 up with another similar part - and I don't recall there was anything
else quite like it in general use - it had a fairly good spectrum for
measurement applications, but a rather noticeable cyclic element to the
sound.  The latter was a bit of a drawback for use as an audible noise
source in synthesizers...

More... (looser matching)
- Last day of these posts
- In 1997 , 1998 only
- Today
- New search...