Analogue systems

The most successful method for me has been the following:

1) First find the tuning pot on the circuit board.  It's on the left circuit
board near the top (when looking at the module from the front).  I think it
has a label saying "CV scale."  Get yourself a long skinny screwdriver to
adjust this.

2) You need a tuning instrument.  A chromatic tuner will work but something
far better is a frequency counter.  I used a multimeter that has such a
function:
http://www.radioshack.com/product/index.jsp?productId=2103175&CAWELAID=107590107

3) Make sure your CV source can put out exactly 0V and 1V.  Calibrate your
keyboard with the voltmeter, or if it already matches up to your other
oscillator, you can just take it as it is.

4) Now set up the output of the oscillator to be read by the frequency
counter (probably square wave is best).  Give the RS95e 0V and then 1V,
noting the frequencies.  The second frequency needs to be EXACTLY TWICE the
first frequency.  If not then you need to adjust.

5) Now if it's off, turn the screw slightly one way or the other.  I forget
which way is sharp and which way flat but it's a one-to-one function so
you'll figure it out in a few seconds.  Now the tricky part is that changing
the CV scale will also offset the CV zero point by a bit.  You could
continually adjust the CV zero each time to get it back to where it was, but
this is tiresome.  Instead, just measure the frequency again with 0V and 1V,
and see if you get the second number as exactly 2 times the first number.
Your first number will be different than before, but that's OK.  Having a
calculator at your side with speed this up.

6) Getting the scale right is a trial and error process and will probably
take a while.  Make small movements and be patient.  When you've finally got
the scale correct, then you can adjust the zero point to where you want it.
There's a separate pot for this and it will not affect the scaling.

Hopefully that was not confusing!

Best,
Monroe



On Wed, Mar 17, 2010 at 4:42 AM, marcneyen <marcneyen@yahoo.com> wrote:

>
>
> Hello,
> my first post here.
> Finally got 2 RS95e in an attempt to expand to 4 for polyphonic playing.
> So far i'm really happy with their sound but unfortunately one is not very
> well calibrated (out of tune) while the other one is rock stable.
> On 1 octave interval its pretty noticeable already and 3 octaves are about
> half a tone of.
> I'm pretty sure I'll manage to get it back into tune but was wondering if
> anyone had attempted (and succeeded) to do this.
> Thanks in advance for any tips.
> greets,
> Marc
>
>  
>


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