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DIY Stompboxes => Building your own stompbox => Topic started by: runmikeyrun on November 23, 2009, 02:21:24 PM

Title: random number generator that's not really that random
Post by: runmikeyrun on November 23, 2009, 02:21:24 PM
i built the random number generator the other day and while it does work O.K. it isn't as jumpy and glitchy as some of the sound samples i've heard, especially when i use it on my bass.  On bass it seems i'll get one "jump" an octave down for each note i hit, which isn't even that noticeable on low notes.  On guitar i get a few jumps around but that's it.  I've switched trannies an infinite number of times with little effect; right now i have a 4401 @ #1 and 2n2222a for the rest which is giving the best (yet limited) results.

The only mod i did was replace the 100k fb resistor with a 100k pot.  Even subbing that with a straight 100k resistor doesn't make it work properly.  Any ideas?

Thanks in advance for any help.

p.s. i used the "smaller" vero layout on the other recent RNG thread:
(http://i114.photobucket.com/albums/n273/rousejeremy/Random_Number_Vero.gif)
Title: Re: random number generator that's not really that random
Post by: frequencycentral on November 23, 2009, 02:31:05 PM
Time for the cartoon again?

(http://www.virtualp.us/Dilbert-Oct_25_001.jpg)
Title: Re: random number generator that's not really that random
Post by: runmikeyrun on November 23, 2009, 11:07:06 PM
 :icon_cry:  i like that cartoon, but i'm really trying to figure out what went wrong, if anything... hoping someone has had a similar experience.
Title: Re: random number generator that's not really that random
Post by: rousejeremy on November 24, 2009, 12:05:55 AM
What happens to the effect when you adjust the pot?
Title: Re: random number generator that's not really that random
Post by: WhenBoredomPeaks on November 24, 2009, 06:27:44 AM
Wow you gave me an idea for a mega project. (Which i never gonna realize anyways.)

I gonna make a code which gonna get random numbers from the site http://www.random.org/ and gonna stream them into the arduino via serial port.
Then the values will be sent to the digital potentiometer on the readboard which will replace an existing pot or resistor and this way i will have some truly random stuff.

Or maybe arduino's inbuilt random commad is enough.
Title: Re: random number generator that's not really that random
Post by: runmikeyrun on November 24, 2009, 07:34:11 AM
when i adjust the pot it goes from a very compressed fuzz (zero resistance) to a less compressed fuzz with the octaves (full resistance).  I have it mounted in a wah shell.
Title: Re: random number generator that's not really that random
Post by: rousejeremy on November 24, 2009, 08:42:28 AM
Since it's on a vero, check all your track cuts and make sure there are no solder bridges anywhere. I use a magnifying glass under a light o check mine.
I once had a RM Octavia that didn't have unity gain. 3 months later I looked at it again and found a hairline solder bridge. You never know.
Title: Re: random number generator that's not really that random
Post by: runmikeyrun on November 24, 2009, 10:36:56 PM
I will do that... i checked my cuts already with an ohmmeter but will look for bridges and the like.  i have one of those magnifying glasses with the light built into it.  Thanks for the tip!
Title: Re: random number generator that's not really that random
Post by: runmikeyrun on November 25, 2009, 11:38:55 PM
I went over all my traces tonight, scraped through them all and along all the tracks with an xacto knife.  While i couldn't see anything connecting, it definitely works better now than it did before.  Thanks for the tip Jeremy!