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Cgs synth

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Re: Bi-N-Tic Damping pot wiring is backwards on the schematic

2006-05-28 by sasami@hotkey.net.au

There is a 10k missing from the schematic here too. Th board and wiring
diagram, however, are correct.

Ken

>If you have output level problems with the Bi-N-Tic this may be your
>problem. The wiper and top of the Damping pot are reversed on the
>Bi-N-Tic filter schematic. I thought it looked odd, but I wired it as
>shown at first. This is the symptom: the damping pot has a working
>range only near zero, and if turned to zero the output of the filter
>just about disappears. If you look closely, you'll notice that the pot
>wiper (as shown on schematic) is connected to IC2 pin 6, the output of
>an op amp. When Damping is turned all the way down, as originally
>wired, this op amp output is shorted to ground. (No damage results
>though.) The schematic also does not show the 10K resistor in series
>with IC1 pin 3. The fix is easy: just swap the center and top wires on
>the pot. Now the output of IC2 is going to the top of the pot, and the
>wiper is connected to the 10K resistor. This change makes a HUGE
>difference to the sound. It works correctly now.
>
>Richard Brewster
>http://www.pugix.com
>
>
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>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
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_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

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