[sdiy] Pin 14 on the 3340

[Oakley Sound]

TW > I sometimes get emails from customers asking me questions about the 
implementation of the AS3340 in various old synths...

Changing the pulse width output load to a minimum of 51K can be 
troublesome. The CEM3340 was happy with 10K and some synths rely on this.

The OB-Sx has a two resistor 10K:22K network to bring the pulse 
amplitude down to 10V. So all 12 VCOs needed to be changed to a 22K:30K 
combination to prevent the pulse width from affecting the pitch. This 
could still be the root of my problem but the loading problem seems to 
be related to the issue that Matthias had with PW affecting the tuning 
rather than instability.

The AS3340 does seem to be more pitch stable than the CEM3340 though - 
except for the weirdness with pulse width.

Interesting stuff for sure.

Tony

www.oakleysound.com