[sdiy] Re: yamaha CS01 with missing LFO: a problem to solve

[Antonio Tuzzi]

Hello Bob,

guess what... is "just" a slider problem.

I was checking all the components, but always missing to check the
slider... (never assume something is working...)

the RD1M is dead: the wiper has broken contact strips.

Do you have any idea about a substitute ?  Or a part number ? (is a
35mm x 8mm x 8mm slider)
I hope the slider is easier to find that the main yamaha chip! (or I'm wrong ?)

I could use a standard too.. (not reversed A1M or B1M)

thank you
at


On 9/4/07, Bob Weigel <sounddoctorin at imt.net> wrote:
> Not sure which pot you mean fore sure.  LFO Speed?  The value if so is
> called "RD1M"  A reverse special taper I'd guess.
>
>
> >oops
> >
> >maybe the pot is 1m log....
> >
> >(cannot read on the schematics:
> >www.matrixsynth.com/blog/media/yamaha/cs01sch/
> >)
> >
> >
> >On 9/4/07, Antonio Tuzzi <antoniotuzzi at gmail.com> wrote:
> >
> >
> >>Hello Friends,
> >>
> >>I have this cs01 and is missing the LFO signal, I think is a case of
> >>bad YM10150 (the main yamaha IC in the keyboard).
> >>
> >>what I have available on the board is
> >>
> >>10 k lin slider
> >>+
> >>22k resistor
> >>+
> >>0.033 uf cap
> >>
> >>the lfo range was
> >>0.3 to 22 hz
> >>
> >>the power available is  -9v to 0v
> >>
> >>question:
> >>can I add just an opamp with these elements to get back an LFO in the
> >>same range?
> >>
> >>(maybe adding just a couple of passive components...)
> >>
> >>
> >>thank you
> >>
> >>at
> >>
> >>
> >>
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> >
> >
>