Ultrasonic Directional Loudspeaker - March-2011

[samdak]

Hi,

I had recently bought the Kit for "Ultrasonic directional speaker" that appeared in March-2011 Edition of Elektor, the kit comprises of parts for 1-Channel (though the driver PCB supports for 2-Channels) and the Ultrasonic Transducers Array (x50 piezoelectric transducers). With proper supply of 12v i am able to hear the directional sound produced by the driver kit, but not the music/audio when i have the audio jack connected to a stereo system.

Also i did observe that the MOSFET drivers IRF540 gets heated up very soon.

Not sure what's happening and why i am not able to hear the music/audio on the speakers.

Any suggestion/help is appreciated.

thanks
Sam

[yvonne]

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[-=db=-]

Hey,
I'd like to get a hold of that kit, who was the advertiser? I don't get the magazine so I can't look it up. If you can provide a web link, that would be great.
Did you get your problem resolved? How well does it work? Once I get my kit, if you need any help getting it working, let me know.

[Elektor Editor]

Have a look here

http://www.elektor.com/magazines/2011/march/ultrasonic-directive-speaker.1707039.lynkx?

You can download the article using the e-credits you got on registering to this website.

Jan