retrieving an input signal in to labview 4.1

[Giacomo]

Dear All,

I need to obtain a sound signal from an external microphone and record and display this on labview 4.1.

Can anybody help

Giacomo

[Wasntme]

Hi Giacomo,

If you have an NI DAQ card then it's quite a straight forward Analog Input from the mic into the daq card.

If it's a sound card that you will be acquiring through then it's more of a problem. Labview version 5.0 brought in a Sound Palette for direct access of .wav files. There are no examples that I can find for recording and displaying sound in 4.1.

For a more definative answer please supply me with more info. Some information on the sound to be recordered e.g. lenght etc. A list of hardware you have available, what spec PC and OS you're running and so on.

Many thanks,

[Giacomo]

Hi M.Poole

Thankyou for answering my question so promptly, hopefully you will be anle to help me.

Im basically trying to create a virtual echo sounder. My plan is to record a sound pulse that only lasts for 1-2 seconds and repeatedly trasnmit this through amplifier to a speaker. I then need to recieve the 'echo' signal from a microphone and record and display the intensity of that signal and compare it to my original output signal. so the main problem i have is trying to recieve the sound back into labview from a microphone and record and display the signal. I have managed to play sound from labview using the 'playsound' example. As mentioned, the length of the signal will be around 1-2 seconds. I am running labview 4.1 on a sony vaio laptop and my OS is XP. I have only to USB connections available and my intention is to plug the micrpphone into the microphone port on my laptop and plug the amplifier and speakers in to my speaker port.

Thankyou

Giacomo

[Wasntme]

Hi again Giacomo,

The easiest answer I can give you is upgrade.

As mentioned in my first post we introduced a 'Sound' palette into Labview from version 5 onwards.
As you are looking to use the laptops onboard sound hardware then its most likely the files we be saved in .wav format. At the moment Labview ships with example programs that can read and write wav files. Pretty much all the work has been done for you already.
Unfortunately I have no information I can give you to show how this can be done with the old Labview 4.1. It's possible but will require a lot of programming.

My best advice is to get hold of the Evaluation version of Labview and check out the Wave_File_Player.vi. You can also try it online by visiting www.ni.com/trylabview and viewing the above demo.

Hope this helps,