>
> You can tell if the problem is the switch or the LED by seeing if

the switch

> actually does anything. By itself, pressing the switch toggles the

function

> of the MASTER slider between volume and tuning. If it's the LED, it's an
> easy fix, although anything that requires removing the panel boards

is a bit

> dangerous at this point, since the membrane switch tails might be on the
> verge of cracking in a unit this old. If that was the problem and it

was my

> unit, I'd leave well enough alone. If it's really the switch,

though, you

> could replace just that switch with a mechanical one.
>
> > Also, can this function be accessed through an external midi
> > control? Or does the synth require a repair.
>
> There are System Exclusive messages that can simulate the pressing of
> switches. And of course the Tune Request byte does the same thing as

LOWER

> FUNCTION, TUNE ALL.
>

Thanks for the reply Paul. How would I go about using a system
exclusive message to simulate the pressing of this switch? Is there
documentation for it somewhere? And what is the tune request byte?