Digital noise

[I am not a number. I am an unbound variable. 16-Sep-1993 0950]

Timothy Newsham writes:

>Last time I was fingering through an analog parts catalog under the
>telephony section I noticed a bunch of parts that generate audio-noise.
>Maybe some of these would be suitable (if they dont use an internal
>digital state machine to generate the noise).

Unfortunately, last time I checked, they used a fairly short internal
PRNG to generate the "noise" (which means it's not noise at all, it's 
completely correllated and repeating, it just _sounds_ like noise to
a human ear.

To get real random noise, try using a transistor "backwards", as a 
zener diode.  Then look at the voltage- it's quite "noisy", esp. if you
use a decent-sized series resistor (try 100Kohms).

	-Bill (done this before)...