[sdiy] Akai AX80 weird PWM behaviour on Voice 8 when Saw wave enabled

james meagher w.james.meagher at gmail.com
Sat Jul 14 01:35:09 CEST 2012

> Pull everything out and reseat it?
> The ICs that are socketed, one by one, pull them out and put them in again. Twice if they look tarnished. Same with the connectors. Maybe you've done this?
> Sometimes it works wonders.
> HTH,
> Tom

Original Voice 8, DCO1 waves being overly modulated (to the point of
collapse) seems to have been solved. It appears that the trimmer was
not the issue but that D805 was leaking a significant charge into T804
(which was then spreading it around like wildfire). Bad Diode by the
looks of things. Working well now.

Thanks for reseating tip Tom - I'll be sure to do that when I put the
new battery in. So far, now that I've changed all the anomalous
parameter values to real numbers everything seems to be saving
properly and nothing has reverted. Nevertheless I'm going to replace
that battery and reseat as you've suggested.

Many thanks again to all those who have made suggestions or
commiserated. When my parts arrive I should solve the issue with DCO2
on Voice 4 and then have perfectly working AX80! WooooHoooo!


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