Fw: simple schematics

[Scott Gravenhorst]

"Roel Das" <Roel.Das at student.groept.be> wrote:
>I actually meant, when you use a pulse-waveform to clock the random
>generator.
>Why would you need a freq much higher than the audio range? (I realize that
>the random generator will produce series of 2's and O's) Can't you just use
>a VCO
>tuned a few octaves higher with a pulsewave (I have built a working VCO a
>few months ago)?

I've done this.  One can play "noise melodies" via the control
voltage on the VCO clocking the shiftregister.  Mine is 24 bit CMOS.
The more bits, the longer the repeat cycle and the faster you can clock
it.  To my ears, the faster the clock, the "smoother" the noise as 
well as the noise spectrum being pushed up.  The slower the clock,
especially at a certain point, the thumpier and more "geiger counter"
like it gets.  Using a VCF with rez can make the noise melody tonality 
more prominent.

>
>And, are these random generators available in logic components?

I built mine of standard CD4xxx stuff.  You need some shift reg
ICs and an XOR and a couple of others.

>And second, would the up down counter be worth the trouble?

Not sure what that would be for...  I take my output off of one of
the shift register bits and feed it into a low pass filter.

-- Scott Gravenhorst                    | Linux Rex, Linux Vobiscum
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