## What Does It Do? **The Coqui: a simple device to read a sensor via an audible tone.** We're exploring using audio frequencies to convey sensor readings -- like a modem, but even simpler -- in order to make sensor readings more accessible for people (or to enable data transmission over ubiquitous audio jacks on PCs and smartphones). Look for recent updates on Public Lab [here]( ## Activities This is a list of community-generated guides for specific applications using your coqui. These [activities can be categorized](, and some may be more reproduced -- or reproducible -- than others. Try them out to build your skills, and help improve them by leaving comments. Together, we can repeat and refine the activities into experiments. [activities:coqui] **** ## Frequently Asked Questions [questions:coqui] **** [![coquibb.JPG](]( A Coqui is a simple, inexpensive, open source device that generates an audible tone that is based on any electric resistance-based measurement. For example, a Coqui can measure: * conductivity of liquids * temperature * ambient light ##Build a Coqui Instructions on the breadboard-based "BBv1.0" edition of the Coqui can be found here: ###Notes: - For more information about the Coqui, post a question to the "water quality" mailing list [here](!forum/plots-waterquality)) (also listed in the left sidebar) - The github repo for a PCB version of the coqui is [here]( The Coqu&iacute; is a circuit that allows you to 'hear' the readings from various sensors. Once the Coqu&iacute; is assembled, you'll be able to 'hear' the conductivity of a solution, the temperature of a room, or the color of a pH test strip. </br></br> The design was named (onomatopeically) after the <a href="">several species of small frogs </a> which have a loud, distinctive call at night.</br></br> <iframe src="//;byline=0&amp;portrait=0" width="600" height="393" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe> ### Demo Coqui applications - [Testing the conductivity of a solution]( <iframe width="560" height="315" src="//" frameborder="0" allowfullscreen></iframe> - [Reacting to an LED with sound]( <iframe width="560" height="315" src="//" frameborder="0" allowfullscreen></iframe> - [Assessing ambient light levels]( <iframe width="560" height="315" src="//" framebord"0" allowfullscreen></iframe> - [Assessing temperature with a thermistor]( <iframe width="560" height="315" src="//" frameborder="0" allowfullscreen></iframe> - [Sending water quality voicemails with a coqui using]( [![water-vmail.png](]( ### Building your own Coqui - [Coqui BBv1.0]( a breadboarded version of the Coqui ### Building Coqui sensors - Making a conductivity probe from a [bottle cap and two metal screws](

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