[sdiy] calling for 606 /808 gurus

[VINTVOLT]

Hi, 
I'm currently modding a tr-606 for a friend. I've already modded quite 
a lot of things *based* on the MIX magazine modifications. Now the 
owner definitely wants decay for the Open HH. I've looked around but 
this particular mod is nowhere described.
So I began messing around with capacitor and resistor values and found 
out that increasing R167 (1 Meg) effectively increases decay time. 
But the problem is now that when the decay time is set long, the closed 
HH does NOT shut off the Open HH anymore...

Not giving up, I digged out the TR-808 schematics to find out that the 
HH circuitry is quite similar (identical in some parts). The 808 does 
decay time in a different way increasing VR3 (2 Meg) The upper terminal 
of this pot is connected to +Vcc

The equivalent resistor on the 606 is R6 (15K) but the upper terminal 
is connected to the TEMPO CLOCK. Can Anybody explain this?
In the block diagram of the 606 you can see that the Envelope Shut off 
block is controlled by the tempo clock!! Why, oh why??

I have not yet tried to modify R6...

Has anybody made this mod?

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