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Coqui conductivity sensor

## 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). ## Latest version The [latest and simplest version of the Coqui](/notes/warren/03-01-2019/build-a-sound-generating-coqui-conductivity-sensor) can be seen in the following images. This version differs from [the previous](/notes/ashkaya/09-17-2016/build-a-coqui-a-simple-water-conductivity-sensor) in a few ways: * smaller, cheaper circuitboard (breadboard) * fewer wires * flatter wires which make it easier to see the circuit However, the circuit is fundamentally the same! Click these images to enlarge: [![IMG_20190123_111639_270.jpg](/i/28988?size=medium)](/i/28988?size=original) [![IMG_20190118_205609_421.jpg](/i/32338?s=m)](/i/32338?s=o) ## Assemble the Coqui Here are a few guides to building different versions of the Coqui: [notes:grid:activity:coqui] ## Coqui versions The Coqui has been refined, remixed, and modified plenty over the years. [activities:coqui-version] ## Modify the Coqui [activities:coqui-mods] ## Do something with the Coqui Once you've built a Coqui, here are a few things you can do with it: [notes:grid:activity:coqui-usage] Add an activity or request an activity guide you don't see listed **** ## 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 - The github repo for a more permanent printed circuit board version of the coqui is [here]( The Coquí is a circuit that allows you to 'hear' the readings from various sensors. Once the Coquí 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. The design was named (onomatopeically) after the several species of small frogs which have a loud, distinctive call at night. ### Demo Coqui applications - [Testing the conductivity of a solution]( - [Reacting to an LED with sound]( - [Assessing ambient light levels]( - [Assessing temperature with a thermistor]( - [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]( ## Parts list See the initial parts list here: #13459 and #11209 for a DigiKey shopping cart link at $19 per kit. And @kanarinka mentions: > there are a couple other things that are helpful to have that are not shown (like the probe made from the top of a water bottle with two screws in it and alligator clips to attach that to the breadboard) Scans of an invoice from DigiKey: [![Screenshot_2018-02-28_at_9.59.17_AM.png](]( [![Screenshot_2018-02-28_at_9.59.46_AM.png](]( ...

Author Comment Last activity Moderation
xose "Deffinitely! On wednesday i'll post the mod ;) " | Read more » over 5 years ago
warren "This is really cool. A recording would mean you could calibrate it later, too -- if you maybe dipped it in 2 different high and low solutions of kn..." | Read more » over 5 years ago
warren "Oooooohhhhhhhh!!!!! " | Read more » over 5 years ago
xose "Added a 3.5mm jack to record the wave ;D " | Read more » over 5 years ago
asnow "Great thank you Kina! " | Read more » over 5 years ago
asnow "Thanks Chris! " | Read more » over 5 years ago
kinasmith "both parts are very similar. the TLC555IP has a wider operating temperature (-40to+85c), and will work down to 3volt power input. From the datashee..." | Read more » over 5 years ago
cfastie "I am going to guess: Yes, they are interchangeable for your application. DigiKey links to the same data sheet for both of them. Page 3 of the datas..." | Read more » over 5 years ago
asnow "@kinasmith @cfastie @donblair thanks! " | Read more » over 5 years ago
asnow " " | Read more » over 5 years ago
warren "Hi! I made a bookletized version of the pdf for printing on half-letter-sized paper -- Booklet_Sensor_Journalism_Final.pdf " | Read more » over 5 years ago
warren "@kanarinka - we're planning to order a bunch of these to test out at MakeFaire SF at the end of may -- getting ready for a big order, and printing ..." | Read more » over 5 years ago
warren " " | Read more » over 5 years ago
warren "Hi, Catherine! This is so great. We're going to get this rolling (@bronwen and @amanda and I) to carry a Community Kit with these, as well. We're l..." | Read more » over 5 years ago
warren "I've submitted a bug report with steps to fix: -- sorry! " | Read more » almost 7 years ago
warren "I'm actually having trouble editing this page -- must be a bug due to it being "converted" to a question instead of being one from the start. " | Read more » almost 7 years ago
warren "Actually i haven't tried marking a question as an activity; i guess it works? Maybe not a good practice? I dunno -- new territory for us! As to you..." | Read more » almost 7 years ago
pdhixenbaugh "Also: I'm not sure if you're testing (1) Hot Tap Water vs Cold Tap Water, or (2) Hot Tap Water vs. Hot Tap Water which has cooled down. Put another..." | Read more » almost 7 years ago
pdhixenbaugh "So both questions and research notes can be marked as an activity? And at some point, folks replicating the activity can post their answers? I like..." | Read more » almost 7 years ago
donblair "Hallo! I haven't had great luck with Digikey shopping carts sticking around, so it might be better to put direct links to parts in e.g. a wiki ......" | Read more » about 7 years ago
kanarinka "I'm actually not sure about this - @donblair - do you know the answer? " | Read more » about 7 years ago
warren "I renamed this and converted it to a "Question" in the new Q&A system " | Read more » about 7 years ago
pdhixenbaugh "I'm intrigued by the speaker resistance - can that be measured with a multimeter - and what are the rules of thumb for not burning out the timer? " | Read more » about 7 years ago
kgradow1 " " | Read more » about 7 years ago