Can't the problem be reduced by slightly bending the upper right
(note ?) contactleaf a bit down, so the contact will close just a
little bit earlier and will not open again while the key is bouncing ?
I guess the right switch starts the trigger, the left switch
determines initial velocity isn't it ?
Maybe there's a weak spot on the contact-metal and cleaning it will
reduce double-triggering too?
--- In yamahacs80@yahoogroups.com, The OldCrow <oldcrow@...> wrote:
>
> Errant triggers are caused by contact bounce, which is due to two
> things. First is the design of the weighted action itself. While
> well-balanced, each key ultimately strikes a small rubber pad,which
is
> in fact the force-sensing resistor array's cover delivering that
> immaculate aftertouch. This results in a small bounce of the far
end of
> the key's 'rib' which is where the actual switch(es) are. At times
this
> bounce can cause a retriggering of envelopes. Second is the age of
the
> switches. Their design is going to last a hundred years, but
contacts
> do wear down, and they are already 30 years old. A little less
contact
> facing means a slightly wider contact gap, and a wider gap means
the
> above mentioned bounce has a greater chance of retriggering a note
> envelope/rotation.
>
> I tinkered with a corrective circuit, but am unsure if the
correction
> is 'better' (essentially a one-shot with a time of 50ms or so for
each
> trigger switch--16 in all).
>
> Scott
> /∗∗/
>
> JH. wrote:
> >> I noticed some of your keys double-trigger the notes like mine
does.
> >> How can we fix that?
> >>
> >
> > I've no idea.
> > It doesn't bother me much, though. As long as I don't get _wrong_
notes.
> > But I sometimes get them; I suspect when a bouncing key triggers
the first voice not long enough to fully charge the capacitor of the
S&H?
> >
> > JH.
> >
>