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Archive for the ‘microphone’ Category

Mag
18

Manipulate your voice with Mimic Monster and Intel Edison

arduino, ArduinoCertified, edison, Featured, Intel Edison, microphone, speaker, tutorial, USB sound card, video, voice Commenti disabilitati su Manipulate your voice with Mimic Monster and Intel Edison 

Monster_post2

It’s time to introduce you to another great tutorial made for  Intel Edison.  Mimic Monster is a project allowing you to record soundbites and playing them back manipulated.
In this step-by-step project, everyone who is interested in audio features and mods , can find useful information on how to manipulate audio files and create amazing effects from your voice.

Grawr! It’s a mimic monster! What did you say? Grawr! It’s the mimic monster!

Having landed on Earth, this little alien needs you to teach it how to speak. Speak into its audio antenna and it will repeat your words back. Press a button and change its pitch. In this tutorial, you will learn in more detail, how to work with a USB sound card, a microphone, and a speaker.


Before you begin, make sure you’ve followed through Intel® Edison Getting Started guide, and our previous tutorial, the Intel® Edison mini-breakout Getting Started Guide.

Monster_post1

 Check the other tutorials of the series.

Feb
10

Converting Morse Code to Text with Arduino

Amateur Radio, arduino, arduino hacks, ham, microphone, morse, Morse Code, radio, speaker, translate Commenti disabilitati su Converting Morse Code to Text with Arduino 

Morse code used to be widely used around the globe. Before voice transmissions were possible over radio, Morse code was all the rage. Nowadays, it’s been replaced with more sophisticated technologies that allow us to transmit voice, or data much faster and more efficiently. You don’t even need to know Morse code to get an amateur radio license any more. That doesn’t mean that Morse code is dead, though. There are still plenty of hobbyists out there practicing for the fun of it.

[Dan] decided to take a shortcut and use some modern technology to make it easier to translate Morse code back into readable text. His project log is a good example of the natural progression we all make when we are learning something new. He started out with an Arduino and a simple microphone. He wrote a basic sketch to read the input from the microphone and output the perceived volume over a Serial monitor as a series of asterisks. The more asterisks, the louder the signal. He calibrated the system so that a quiet room would read zero.

He found that while this worked, the Arduino was so fast that it detected very short pulses that the human ear could not detect. This would throw off his readings and needed to be smoothed out. If you are familiar with button debouncing then you get the idea. He ended up just averaging a few samples at a time, which worked out nicely.

The next iteration of the software added the ability to detect each legitimate beep from the Morse code signal. He cleared away anything too short. The result was a series of long and short chains of asterisks, representing long or short beeps. The third iteration translated these chains into dots and dashes. This version could also detect longer pauses between words to make things more readable.

Finally, [Dan] added a sort of lookup table to translate the dots and dashes back into ASCII characters. Now he can rest easy while the Arduino does all of the hard work. If you’re wondering why anyone would want to learn Morse code these days, it’s still a very simple way for humans to communicate long distances without the aid of a computer.


Filed under: Arduino Hacks
Giu
09

Echolocation pinpoints where a gunshot came from

acoustic location, arduino hacks, digital audio hacks, echo location, echolocation, microphone Commenti disabilitati su Echolocation pinpoints where a gunshot came from 

echolocating-gunshots

[Kripthor] suspected that hunters were getting too near his house. When thinking of a way to quantify this belief he set out to build a triangulation system based on the sound of gunshots. The theory behind it is acoustic location, which is a specialized type echolocation.

The most common example of echolocation is in Bats, who emit ultrasonic noise and listen for its return (echo) to judge the location of objects. [Kripthor] doesn’t need to generate the sound himself, he just needs to pick it up at different points. The time difference from the three samples can be used to triangulate coordinates as seen in the image above.

He first tried using a PC sound card to collect the samples. The stereo input only provides two channels so he tinkered around with a 555-based multiplexing circuit to sample from three. The circuit noise created was just too great so he transitioned to using an Arduino. The ADC samples from each microphone via an NPN transistor which is used as a simple amplifier.

This brings to mind a homebrew sonar hack from way back.


Filed under: Arduino Hacks, digital audio hacks


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