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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
liz "Since the two main ways to control the sound are the saltiness of the water and the size of the capacitor, it would be cool if this list of parts i..." | Read more » over 7 years ago
liz "I found a power drill very useful to get the screws into the caps. Here's what you need to finish the ends of the wires from the alligator clips: ..." | Read more » over 7 years ago
liz "Looks great! maybe we could add a picture of how the cut ends of the alligator clips go into the terminal block? " | Read more » over 7 years ago
majer "me to :) " | Read more » almost 8 years ago
semitones "@donblair is there text that goes along with this too? " | Read more » almost 8 years ago
warren "Hi, Amy! I think @donblair is busy deploying Riffles in Colombia, but @wmacfarl made an Upverter version of the circuit that's quite compact -- her..." | Read more » about 8 years ago
GreenChemist "Hi Warren, Thanks. I am a chemical engineer who always worked in Medical and Safety industries. Currently I am looking for a new position anywhere ..." | Read more » about 8 years ago
warren "It's a good point -- esp. always to be sure that the scope of the test is clear. The idea here was more exploratory, but in general this kind of co..." | Read more » about 8 years ago
GreenChemist "Hi Warren, Indeed the test would not find the bacteria, you need a polymerase chain reaction (a PCR test), or grow a culture. I am not sure if this..." | Read more » about 8 years ago
warren "Hi, Don - sorry, you never wrote back so I hadn't changed the title until now - it now says "Coqui" only - thanks. The conclusion you draw: it s..." | Read more » about 8 years ago
GreenChemist "Hi Warren, I am new at this, so maybe I missing the ball, but isn't one of the reason why not to drink from the hot tap the possible presence of L..." | Read more » about 8 years ago
danbeavers " is anoth..." | Read more » over 8 years ago
warren " PCB on the right, of course. " | Read more » over 8 years ago
warren "Will Macfarlane (@wmacfarl) kept working on this and has a more compact version which we're not quite sure works. There may be a problem with the 5..." | Read more » over 8 years ago
liz "thank you for this understandable report back, i really appreciate it! " | Read more » over 8 years ago
JeanellSullivan "I will be attending! " | Read more » over 8 years ago
abbeyghart "I will be attending! " | Read more » over 8 years ago
Nashblackcat "@Mathew Mat: It is great for insulation! ASAS has it cheap so you can try it out and not break the bank." | Read more » over 8 years ago
mathew "@cfastie I guess I can't guarantee they didn't leak a bit, but in my experience the rice sticks to the side of the bottle if there is moisture. I'..." | Read more » over 8 years ago
Nashblackcat "Not sure if this would be an option but Self-fusing Silicone Tape works very well for sealing even in wet and underwater conditions. " | Read more » over 8 years ago
cfastie "That's a great idea to use rice to make the bottle non-compressible. It can also keep your payload dry if a little water leaks in. For the testing ..." | Read more » over 8 years ago
mathew "i've tried heat shrink tubing in other projects-- I don't find that it provides a perfect seal and it has difficulty sticking to glues since its us..." | Read more » over 8 years ago
amysoyka "Have you tried using heat shrink wrap yet as a sealant? Electrical tape also works as shrink wrap - just apply some stream/heat to it and it tight..." | Read more » over 8 years ago
jlwhitbeck "I will be attending! " | Read more » over 8 years ago