Re: Random Number Generator PCB

[k3yPr0gg3r]

Hi,

So...a vendor that actually sells this PCB includes a MOD for a two knob version in the build docs, but can't explain the specifics to me. He states that an external pot can be "swapped out" for R3 (100k). My questions are: 1. Is it an A100K or B100K? 2. There are only two connections. Which lugs do I attach, and do I wire the empty lug to a connected lug or leave it empty?

Thank you for your help!!!

[antonis]

I've completely no idea about what you're talking but...

How did you manage to create a topic with "Re:" from the very first post... 

[Marcos - Munky]

I think I have an idea of what you're talking about. It's Doug Deeper's Random Number Generator, an early Mid-Fi product. If yes, it's a interesting effect, I remember to have built one long time ago, and now maybe I'll add it into my to build list again

To answer your question, I know there's two versions of it, one with one pot and one with two pots. Basically, one have a fixed value resistor (a 100K one) and other have a variable value resistor (a 100K pot). Check those schematics and you'll see the difference:
http://www.diystompboxes.com/smfforum/index.php?topic=58763.msg457906
http://www.diystompboxes.com/smfforum/index.php?topic=56529.msg436805
About the taper, I don't know if A or B works better. Both works, what changes is how the resistance changes as the pot is turned.

[k3yPr0gg3r]

Thanks for the info. I just need to know about lug attachment whether it's 1 and 2 with 3 left open, or 1 and 3 with 2 wired to 3, etc. I'll look and see if I can figure it out...

[Marcos - Munky]

Since I built it a long time ago, I don't really remember what does this pot do. I suggest you to connect lugs 1 and 2 together. Then connect lugs 1 and 2 to the collector of the PN2222 transistor, and lug 3 to the 2N3904 transistor next to the output, and try it out. If you think the pot is acting reversely, just invert the connections and connect lugs 1 and 2 to the 2N3904 and lug 3 to the PN2222.