[sdiy] 909 hh sample selection

[gregory zifcak]

hi all,
i'm knee deep in 909 mods, and i'm wondering how the hi hat samples are 
selected. i've seen posts in the AH archives referring to a mod that swaps 
the closed and open samples but not the envelopes. ideally i'd like to have 
the envelopes stay triggered by the correct triggers, but have a switch to 
determine the sample for the closed envelope, and a switch to determine the 
sample for the open envelope. so the possible combos would be closed/open, 
closed/closed, open/closed, and open/open.

circuit details (once again) are at http://hardware.freepage.de/raf909/ 
under "circuit analysis" and "hihat and cymbals."

from the description, d196-198 sounds like the area i need to alter, but i 
don't understand how that configuration of diodes is working. any insight 
would be greatly appreciated.

thanks in advance,
greg