Low End Off the shelf FFT needed

[mchenney]

<mchenney@mindspring.com>

Looking for low cost off the shelf FFT, microphone input equipment to do limited go-no go testing of small DC gearmotors. Cycle time in 2-5 second range.

Thanks

PS: Also background noise cancelation microphones for front end

Dennis McHenney
mchenney@mindspring.com

&lt;dmchenney@merkle-korff.com&gt;

&lt;mchenney@mindspring.com&gt;

 

[butelja]

Consider a PC with a data acquisition card and Labview software from National Instruments.

 

[Hatch]

I use a National Instruments DAQCard 700 (PCMCIA card for a laptop computer) which is low cost. The Labview software has sample (demo) FFT analyzers which you could use. Check out the National Instruments website.

You did not say if you wanted the go-no go testing to be automated. Labview would be ideal for that, but the learning curve is steep (especially for non-electrical engineers) even though the graphical interface is supposed to be easy.

You could also design your own FFT analyzer but as I said before the learning curve is steep.

 

[mchenney]

<dmchenney@merkle-korff.com>

Has anyone ever used a PC sound card and the available share/freeware,or very low cost SW to do this? I know this is an option, but not sure how good it is?

Can an OFF THE SHELF noise cancellation microphone system be used as a front end?



Dennis McHenney
mchenney@mindspring.com

&lt;dmchenney@merkle-korff.com&gt;

&lt;mchenney@mindspring.com&gt;

 

[Rich2001]

Another way to do this is to use a TI-92+ or TI-89 graphing calculator, with a CBL and microphone input. Total cost around $250. Check a physics or math department at a local high school or college to show you this calculator and CBL.

TI makes the calculator and the CBL (calculator Based Lab)
Vernier Software hase the microphones. Neat little device that I use all the time to monitor and log data ( battery powered, handheld) and a lot cheaper than a PC or laptop.

As you might guess I am one of those that straps system to my leg and hook up an accelerator and ride rollercoasters.

Rich

 

[steeno]

This is a reply to rollercoaster-Rich2001 as my request
is boy-ish too:


I have an interest in acoustics and flute playing.
My flutemaker has come up with some new tubes.

He claims that they will produce a better sound
than conventional tubes. I would like to help him
prove this. But how ?

I would like to study vibrating metal tubes somehow
so the quality of their vibration could be studied.

I downloaded a Finite Element Analysis tool only
to learn that it could not handle tubes.

So I put this question here - I know it should
have been a new thread but I couldnt work out
how to start a new thread (!?) - Suppose
I have a head joint mounted on one of these tubes
and make it vibrate. There will be a sound to record,
sure. But what if I want to say something about the
vibration of the tube - in order to be able to
distinguish between tubes manufactured in different
ways (I understand that stretching - or whatever
the English term is ) is an important factor in
tube production.

Any new wild ideas wellcome. Steeno.

 

[steeno]

This is a reply to rollercoaster-Rich2001 as my request
is boy-ish too:


I have an interest in acoustics and flute playing.
My flutemaker has come up with some new tubes.

He claims that they will produce a better sound
than conventional tubes. I would like to help him
prove this. But how ?

I would like to study vibrating metal tubes somehow
so the quality of their vibration could be studied.

I downloaded a Finite Element Analysis tool only
to learn that it could not handle tubes.

So I put this question here - I know it should
have been a new thread but I couldnt work out
how to start a new thread (!?) - Suppose
I have a head joint mounted on one of these tubes
and make it vibrate. There will be a sound to record,
sure. But what if I want to say something about the
vibration of the tube - in order to be able to
distinguish between tubes manufactured in different
ways (I understand that stretching - or whatever
the English term is ) is an important factor in
tube production.

Any new wild ideas wellcome. Steeno.