Okay. But could you use the output of a MIDI-CV converter or a CV
keyboard as your reference and still use this method? It should still
be consistant across all inputs right?
LArry
--- In
ComputerVoltageSources@yahoogroups.com, "John Loffink"
<jloffink@...> wrote:
>
> For calibration you need to measure an amplified value, even if the
> amplification is 1. You can't do that by grounding the signal.
That just
> sets the zero null point.
>
> John Loffink
> The Microtonal Synthesis Web Site
> http://www.microtonal-synthesis.com
> The Wavemakers Synthesizer Web Site
> http://www.wavemakers-synth.com
>
>
> > -----Original Message-----
> > From: ComputerVoltageSources@yahoogroups.com
> > [mailto:ComputerVoltageSources@yahoogroups.com] On Behalf Of Larry T.
> > Sent: Saturday, March 25, 2006 8:03 PM
> > To: ComputerVoltageSources@yahoogroups.com
> > Subject: [ComputerVoltageSources] Re: resistor matching, was RE:
> > Calibrated Inputs
> >
> > Thinking about it, I believe this would also account for varrainces in
> > the ADC's thenselves would'nt it?
> >
> > Larry T.
> >
> > --- In ComputerVoltageSources@yahoogroups.com, "Larry T." <larry@>
> > wrote:
> > >
> > > HI All
> > >
> > > Given that I'm not an EE or even a decent hobby designer, why is
this
> > > calibration such a problem? Why not use trim pots and the Analog
> > > inputs themselves as follows:
> > >
> > > First: Ground the input to be calibrated. (This should ALWAYS be a
> > > constant of 0 right?)
> > >
> > > Second: Run a small program on the modules CPU to continously return
> > > the value of the converters input via the serial port to a 'telnet'
> > > session on a PC or Mac, followed by a Carriage Return and a Line
Feed.
> > > (This will give you a continous dump of the converters value
down the
> > > screen.)
> > >
> > > Third: Adjust the timpot until you get 0.00... as the returned
value,
> > > and it stays that way for a minute or two.
> > >
> > > Would'nt this handle it with NO tools of any kind except those we
> > > already need to use the module anyway?
> > >
> > > Larry T.
> > >
>