Yamaha CS80

Your problem is on the BA board by the sounds of it. Pull the TU and
see if the wire has 13ish volt sitting on it.




--- In yamahacs80@yahoogroups.com, "Heath Finnie" <heathfinnie@...>
wrote:

>
> Hi David,
>
> All three fuses are good and all my supply voltages are there. As

I said, I know the KAS

> board is good because I replaced the entire board after this

problem started and its still

> there.
>
> I also tried calibrating the KAS board and I'm getting very

strange things going on. For

> instance on wire TU the calibration says I should be getting 4.v

for a reference voltage but

> I'm getting almost 13v. None of the VR's are doing anything either.
>
> --- In yamahacs80@yahoogroups.com, David Rogoff <david@> wrote:
> >
> > I've had CS80s do this when I've shorted something and blown one

of the

> > DC fuses in the power supply. Are you sure all the supply

voltages are

> > there?
> >
> > Heath Finnie wrote:
> > > This is a big question here. The CS-80 I'm working on will

barely change pitch all the

> way up
> > > the keyboard now. Some keys will play a little lower but not

much. Now here are the

> > > symptoms:
> > >
> > > I replaced most all the IC's on the sub board. I replaced the

entire KAS board with a

> working
> > > one. Problem does not change.
> > >
> > > The pitch ribbon is having no effect on pitch. Neither is the

pitch knob.

> > >
> > > The channel 2 detune IS working as is the footing sliders.
> > >
> > > Ring modulator is working, sub oscillator is working and so is

all the waveforms.

> > >
> > > Any of the tech guys able to help?
> > >
> > >
> > >
> >
>