At 7:42 PM +0000 09/14/02,
elhardt@... wrote:
>
>As far as future module thoughts, something I'm finding myself needing is
>something that outputs a voltage based on how fast an input voltage
>>changes, then the output voltage drops back to zero when the input stops
>>changing.
That's a differentiator. I have a circuit on Larry's page that outputs a
pulse if dV/dt exceeds a certain value. Rather than following the
differentiator with a comparator, you could follow it with an amp. You
might also want to check out using an LM3900 (National Semiconductor
Application Note 72). Then again, I'm starting to think you can build an
entire synth from 3900's :)
>It's kind of like an AC detector, getting rid of the DC component.
That would be a different circuit.
>I'm needing it to detect the initial breath of air from a breath
>controller and also to eliminate the DC portion of the output of my
>>Spacebeam. If anybody ever does a module
>like this, let me know. I'm trying to think of a way to do it on the
>>current MOTM module line. Maybe I can go through the AC portion of the
>>mixer or something.
Right, you could get that from an AC-coupled circuit. You might want to
try a MOTM-110.