That is certianly strange. The only thing I can note is the trace for
the pitch modulation to CN06-2 does run right through the splash damage
area of the original battery, so perhaps the trace got shorted or opened
and is picking up noise from another part of the circuit. Another guess:
replace C43, which decouples noise on the pitch mod line from CN06-2.
Crow
/∗∗/
On Wed, 3 Sep 2003, cavernosum6 wrote:
> Hi -
> thanks; had a few minutes last night -- disconnected the wheels from
> the front panel (no help); disconnected CN06 - 2 (no help);
> disconnected R9 that feeds the CV mixer IC 8 : problem vanished.
>
> Didn't have any more time (dealing with a dead Prophet 5 power
> supply), but it's aroused my curiosity: why would pulling R9 do the
> job, when pulling CN06-2 had no effect? -- according to the
> schematic, it would be basically the same thing.
>
> Hope to have more time tonight; meanwhile, any further thoughts
> would be appreciated.