Has anyone tries fitting a toggle switch to a A155 module that would
allow bypassing the modification That way, one could switch between
the new style A155 sequencer and a graphic VCO. Seems simple enough
to do.

--- In Doepfer_a100@yahoogroups.com , "Tim Stinchcombe" <timothy@t...>
wrote:

> Had me more of a think on this...
>
> > if the mod is a resistor and a capacitor in the a155
> > control board,then this is the mod i was telling you
> > about...it's the mod for letting you clock the a155
> > from an imperfect clock pulse(with not sharp
>
> ...and I don't think this can be the reason (the clock pulse goes
> through 2 gates anyway, which should sharpen any sluggish pulse up
> plenty!). But I do now believe _this_ must be the reason:
>
> > edges).also,with this mod ,you can step manualy the
> > sequencer from the tiny step button more
> > properly(without almost jumping
> > steps...).
>
> Without the capacitor contact bounce on pushing the clock button
> could well cause it to skip several steps unintentionally. And I
> certainly believe this...
>
> > but,also,this mod stops the a155 from
> > running in high audio frequencies!even if you clock
> > the a155 from an a110 you will notice that,the a155
> > can't run above a certain speed limit(which is rather
> > low!)all these are valid only if we're talking about
> > the same mod,though....
> > by the way,i removed this mod from two of my a155's
> > because i want them to be graphic vco's too!
>
> ...so if you don't care about the skipping several steps problem,
> snipping through one of the wires to break the link formed by the

cap

> & res will let it run at higher speeds. Details for those unsure

what

> we're talking about: the 'control board' is small on the right hand
> side of the module, marked 'A-155-4' on underside ('A-155 board 4'

on

> top); if you have the mod, on the solderside you'll find a

capacitor

> (marked '104') and a 1k resistor (brown, black, red, gold) soldered
> together and bridging two pins of the 4011 IC; cutting or

desoldering

> either end of them or where they join will do it!
>
> Tim