FAT MAN mods and tuning

brad sanders radioactive at geocities.com
Fri Jan 10 11:09:48 CET 1997

I don't have a fatman, but I'm interested because this is probably
going to be my next project. 

How about this?

Use a DPST switch. One side switches whatever trigger you're already
using, the other shorts the base of Q11 to the emitter (ground). If
you look at the truth table, "10" selects decay/sustain, and "11" does
release. So, you should be able to hold the "sustain" portion by not
allowing Q11 to switch on. Let off the switch, and Q11 is driven by
the 8051into "release."  

You'd still use the drum machine for a trigger (just use the other
switch pole to run 5V through a cap to the pad of the drum - otherwise
you could build a Paia MIDI trigger... right?) but given what you
already have the switch seems to me like the easiest fix. This won't
affect the "env" output from the fatman (because it's after the 18K
base resistor), but it should allow you to hold sustain on the
internal VCA.

>I would like to make it into the super fat man.  Right now
>it sits on top of my keyboard stand with the S&S. 
>I have gotten lot's of complements from it when I do shows.
> I was wondering if there is anyway to make a CV/Gate one
>note button that I can press that will play a single note for the
>duration of the pushed time.

> http://radioactive.home.ml.org <-------------------------------

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